13.0.0-102

Fix attrs loop in yXmlText

.jsdoc.json

@@ -17,7 +17,7 @@
     "useCollapsibles": true,
     "collapse": true,
     "resources": {
-      "y-js.org": "yjs.website"
+      "yjs.dev": "Yjs website"
     },
     "logo": {
       "url": "https://user-images.githubusercontent.com/5553757/48975307-61efb100-f06d-11e8-9177-ee895e5916e5.png",

.markdownlint.json

@@ -0,0 +1,4 @@
+{
+  "default": true,
+  "no-inline-html": false
+}

README.v12.md

@@ -0,0 +1,305 @@
+
+# ![Yjs](https://user-images.githubusercontent.com/5553757/48975307-61efb100-f06d-11e8-9177-ee895e5916e5.png)
+
+Yjs is a framework for offline-first p2p shared editing on structured data like
+text, richtext, json, or XML. It is fairly easy to get started, as Yjs hides
+most of the complexity of concurrent editing. For additional information, demos,
+and tutorials visit [y-js.org](http://y-js.org/).
+
+:warning: Checkout the [v13 docs](./README.md) for the upcoming release :warning:
+
+### Extensions
+Yjs only knows how to resolve conflicts on shared data. You have to choose a ..
+
+* *Connector* - a communication protocol that propagates changes to the clients
+* *Database* - a database to store your changes
+* one or more *Types* - that represent the shared data
+
+Connectors, Databases, and Types are available as modules that extend Yjs. Here
+is a list of the modules we know of:
+
+##### Connectors
+
+|Name            | Description               |
+|----------------|-----------------------------------|
+|[webrtc](https://github.com/y-js/y-webrtc) | Propagate updates Browser2Browser via WebRTC|
+|[websockets](https://github.com/y-js/y-websockets-client) | Set up [a central server](https://github.com/y-js/y-websockets-client), and connect to it via websockets |
+|[xmpp](https://github.com/y-js/y-xmpp) | Propagate updates in a XMPP multi-user-chat room ([XEP-0045](http://xmpp.org/extensions/xep-0045.html))|
+|[ipfs](https://github.com/ipfs-labs/y-ipfs-connector) | Connector for the [Interplanetary File System](https://ipfs.io/)!|
+|[test](https://github.com/y-js/y-test) | A Connector for testing purposes. It is designed to simulate delays that happen in worst case scenarios|
+
+##### Database adapters
+
+|Name            | Description               |
+|----------------|-----------------------------------|
+|[memory](https://github.com/y-js/y-memory) | In-memory storage. |
+|[indexeddb](https://github.com/y-js/y-indexeddb) | Offline storage for the browser |
+|[leveldb](https://github.com/y-js/y-leveldb) | Persistent storage for node apps |
+
+##### Types
+
+| Name     | Description       |
+|----------|-------------------|
+|[map](https://github.com/y-js/y-map) | A shared Map implementation. Maps from text to any stringify-able object |
+|[array](https://github.com/y-js/y-array) | A shared Array implementation |
+|[xml](https://github.com/y-js/y-xml) | An implementation of the DOM. You can create a two way binding to Browser DOM objects |
+|[text](https://github.com/y-js/y-text) | Collaborate on text. Supports two way binding to the [Ace Editor](https://ace.c9.io), [CodeMirror](https://codemirror.net/), [Monaco](https://github.com/Microsoft/monaco-editor), textareas, input elements, and HTML elements (e.g. <*h1*>, or <*p*>) |
+|[richtext](https://github.com/y-js/y-richtext) | Collaborate on rich text. Supports two way binding to the [Quill Rich Text Editor](http://quilljs.com/)|
+
+##### Other
+
+| Name      | Description       |
+|-----------|-------------------|
+|[y-element](http://y-js.org/y-element/) | Yjs Polymer Element |
+
+## Use it!
+Install Yjs, and its modules with [bower](http://bower.io/), or
+[npm](https://www.npmjs.org/package/yjs).
+
+### Bower
+
+```
+bower install --save yjs y-array % add all y-* modules you want to use
+```
+You only need to include the `y.js` file. Yjs is able to automatically require
+missing modules.  
+```
+<script src="./bower_components/yjs/y.js"></script>
+```
+
+### CDN
+
+```
+<script src="https://cdn.jsdelivr.net/npm/yjs@12/dist/y.js"></script>
+<script src="https://cdn.jsdelivr.net/npm/y-array@10/dist/y-array.js"></script>
+<script src="https://cdn.jsdelivr.net/npm/y-websockets-client@8/dist/y-websockets-client.js"></script>
+<script src="https://cdn.jsdelivr.net/npm/y-memory@8/dist/y-memory.js"></script>
+<script src="https://cdn.jsdelivr.net/npm/y-map@10/dist/y-map.js"></script>
+<script src="https://cdn.jsdelivr.net/npm/y-text@9/dist/y-text.js"></script>
+// ..
+// do the same for all modules you want to use
+```
+
+### Npm
+
+```
+npm install --save yjs % add all y-* modules you want to use
+```
+
+If you don't include via script tag, you have to explicitly include all modules!
+(Same goes for other module systems)
+```
+var Y = require('yjs')
+require('y-array')(Y) // add the y-array type to Yjs
+require('y-websockets-client')(Y)
+require('y-memory')(Y)
+require('y-map')(Y)
+require('y-text')(Y)
+// ..
+// do the same for all modules you want to use
+```
+
+### ES6 Syntax
+
+```
+import Y from 'yjs'
+import yArray from 'y-array'
+import yWebsocketsClient from 'y-webrtc'
+import yMemory from 'y-memory'
+import yMap from 'y-map'
+import yText from 'y-text'
+// ..
+Y.extend(yArray, yWebsocketsClient, yMemory, yArray, yMap, yText /*, .. */)
+```
+
+# Text editing example
+
+Install dependencies
+```
+bower i yjs y-memory y-webrtc y-array y-text
+```
+
+Here is a simple example of a shared textarea
+```HTML
+  <!DOCTYPE html>
+  <html>
+    <body>
+      <script src="./bower_components/yjs/y.js"></script>
+      <!-- Yjs automatically includes all missing dependencies (browser only) -->
+      <script>
+        Y({
+          db: {
+            name: 'memory' // use memory database adapter.
+            // name: 'indexeddb' // use indexeddb database adapter instead for offline apps
+          },
+          connector: {
+            name: 'webrtc', // use webrtc connector
+            // name: 'websockets-client'
+            // name: 'xmpp'
+            room: 'my-room' // clients connecting to the same room share data
+          },
+          sourceDir: './bower_components', // location of the y-* modules (browser only)
+          share: {
+            textarea: 'Text' // y.share.textarea is of type y-text
+          }
+        }).then(function (y) {
+          // The Yjs instance `y` is available
+          // y.share.* contains the shared types
+
+          // Bind `y.share.textarea` to `<textarea/>`
+          y.share.textarea.bind(document.querySelector('textarea'))
+        })
+      </script>
+      <textarea></textarea>
+    </body>
+  </html>
+```
+
+## Get Help & Give Help
+There are some friendly people on [![Gitter](https://badges.gitter.im/Join%20Chat.svg)](https://gitter.im/y-js/yjs?utm_source=badge&utm_medium=badge&utm_campaign=pr-badge) who are eager to help, and answer questions. Please join!
+
+Report _any_ issues to the
+[Github issue page](https://github.com/y-js/yjs/issues)! I try to fix them very
+soon, if possible.
+
+# API
+
+### Y(options)
+* Y.extend(module1, module2, ..)
+  * Add extensions to Y
+  * `Y.extend(require('y-webrtc'))` has the same semantics as
+    `require('y-webrtc')(Y)`
+* options.db
+  * Will be forwarded to the database adapter. Specify the database adaper on
+    `options.db.name`.
+  * Have a look at the used database adapter repository to see all available
+    options.
+* options.connector
+  * Will be forwarded to the connector adapter. Specify the connector adaper on
+    `options.connector.name`.
+  * All our connectors implement a `room` property. Clients that specify the
+    same room share the same data.
+  * All of our connectors specify an `url` property that defines the connection
+    endpoint of the used connector.
+    * All of our connectors also have a default connection endpoint that you can
+      use for development.
+  * Set `options.connector.generateUserId = true` in order to genenerate a
+    userid, instead of receiving one from the server. This way the `Y(..)` is
+    immediately going to be resolved, without waiting for any confirmation from
+    the server. Use with caution.
+  * Have a look at the used connector repository to see all available options.
+  * *Only if you know what you are doing:* Set
+    `options.connector.preferUntransformed = true` in order receive the shared
+    data untransformed. This is very efficient as the database content is simply
+    copied to this client. This does only work if this client receives content
+    from only one client.
+* options.sourceDir (browser only)
+  * Path where all y-* modules are stored
+  * Defaults to `/bower_components`
+  * Not required when running on `nodejs` / `iojs`
+  * When using nodejs you need to manually extend Yjs:
+```
+var Y = require('yjs')
+// you have to require a db, connector, and *all* types you use!
+require('y-memory')(Y)
+require('y-webrtc')(Y)
+require('y-map')(Y)
+// ..
+```
+* options.share
+  * Specify on `options.share[arbitraryName]` types that are shared among all
+    users.
+  * E.g. Specify `options.share[arbitraryName] = 'Array'` to require y-array and
+    create an y-array type on `y.share[arbitraryName]`.
+  * If userA doesn't specify `options.share[arbitraryName]`, it won't be
+    available for userA.
+  * If userB specifies `options.share[arbitraryName]`, it still won't be
+    available for userA. But all the updates are send from userB to userA.
+  * In contrast to y-map, types on `y.share.*` cannot be overwritten or deleted.
+    Instead, they are merged among all users. This feature is only available on
+    `y.share.*`
+  * Weird behavior: It is supported that two users specify different types with
+    the same property name.
+     E.g. userA specifies `options.share.x = 'Array'`, and userB specifies
+     `options.share.x = 'Text'`. But they only share data if they specified the
+     same type with the same property name
+* options.type (browser only)
+  * Array of modules that Yjs needs to require, before instantiating a shared
+    type.
+  * By default Yjs requires the specified database adapter, the specified
+    connector, and all modules that are used in `options.share.*`
+  * Put all types here that you intend to use, but are not used in y.share.*
+
+### Instantiated Y object (y)
+`Y(options)` returns a promise that is fulfilled when..
+
+* All modules are loaded
+  * The specified database adapter is loaded
+  * The specified connector is loaded
+  * All types are included
+* The connector is initialized, and a unique user id is set (received from the
+  server)
+  * Note: When using y-indexeddb, a retrieved user id is stored on `localStorage`
+
+The promise returns an instance of Y. We denote it with a lower case `y`.
+
+* y.share.*
+  * Instances of the types you specified on options.share.*
+  * y.share.* can only be defined once when you instantiate Y!
+* y.connector is an instance of Y.AbstractConnector
+* y.connector.onUserEvent(function (event) {..})
+  * Observe user events (event.action is either 'userLeft' or 'userJoined')
+* y.connector.whenSynced(listener)
+  * `listener` is executed when y synced with at least one user.
+  * `listener` is not called when no other user is in the same room.
+  * y-websockets-client aways waits to sync with the server
+* y.connector.disconnect()
+  * Force to disconnect this instance from the other instances
+* y.connector.connect()
+  * Try to reconnect to the other instances (needs to be supported by the
+    connector)
+  * Not supported by y-xmpp
+* y.close()
+  * Destroy this object.
+  * Destroys all types (they will throw weird errors if you still use them)
+  * Disconnects from the other instances (via connector)
+  * Returns a promise
+* y.destroy()
+  * calls y.close()
+  * Removes all data from the database
+  * Returns a promise
+* y.db.stopGarbageCollector()
+  * Stop the garbage collector. Call y.db.garbageCollect() to continue garbage
+    collection
+* y.db.gc :: Boolean
+  * Whether gc is turned on
+* y.db.gcTimeout :: Number (defaults to 50000 ms)
+  * Time interval between two garbage collect cycles
+  * It is required that all instances exchanged all messages after two garbage
+    collect cycles (after 100000 ms per default)
+* y.db.userId :: String
+  * The used user id for this client. **Never overwrite this**
+
+### Logging
+Yjs uses [debug](https://github.com/visionmedia/debug) for logging. The flag
+`y*` enables logging for all y-* components. You can selectively remove
+components you are not interested in: E.g. The flag `y*,-y:connector-message`
+will not log the long `y:connector-message` messages.
+
+##### Enable logging in Node.js
+```sh
+DEBUG=y* node app.js
+```
+
+Remove the colors in order to log to a file:
+```sh
+DEBUG_COLORS=0 DEBUG=y* node app.js > log
+```
+
+##### Enable logging in the browser
+```js
+localStorage.debug = 'y*'
+```
+
+## License
+Yjs is licensed under the [MIT License](./LICENSE).

README.v13.md

@@ -1,370 +0,0 @@
-# ![Yjs](https://user-images.githubusercontent.com/5553757/48975307-61efb100-f06d-11e8-9177-ee895e5916e5.png)
-> The shared editing library
-
-Yjs is a library for automatic conflict resolution on shared state. It implements an operation-based CRDT and exposes its internal CRDT model as shared types. Shared types are common data types like `Map` or `Array` with superpowers - changes are automatically distributed to other peers and merged without merge conflicts.
-
-Yjs is **network agnostic** (p2p!), supports many existing **rich text editors**, **offline editing**, **version snapshots**, **shared cursors**, and encodes update messages using **binary protocol encoding**. 
-
-* Chat: [https://gitter.im/y-js/yjs](https://gitter.im/y-js/yjs)
-* Demos: [https://yjs.website/tutorial-prosemirror.html](https://yjs.website/tutorial-prosemirror.html)
-* API Docs: [https://yjs.website/](https://yjs.website/)
-
-### Supported Editors:
-
-| Name                                                   | Cursors | Binding |  Demo |
-|---|:-:|---|---|
-| [ProseMirror](https://prosemirror.net/) | ✔ | [y-prosemirror](http://github.com/y-js/y-prosemirror) | [link](https://yjs.website/tutorial-prosemirror.html) |
-| [Quill](https://quilljs.com/) |  | [y-quill](http://github.com/y-js/y-quill) | [link](https://yjs.website/tutorial-quill.html) |
-| [CodeMirror](https://codemirror.net/) | ✔ | [y-codemirror](http://github.com/y-js/y-codemirror) | [link](https://yjs.website/tutorial-codemirror.html) |
-| [Ace](https://ace.c9.io/) | | [y-ace](http://github.com/y-js/y-ace) | [link]() |
-| [Monaco](https://microsoft.github.io/monaco-editor/) | | [y-monaco](http://github.com/y-js/y-monaco) | [link]() |
-
-### Providers
-
-Setting up the communication between clients, managing awareness information, and storing shared data for offline usage is quite a hassle. *Providers* manage all that for you and are a good off-the-shelf solution
-
-* [y-websockets](http://github.com/y-js/y-websockets)
-* [y-webrtc](http://github.com/y-js/y-webrtc)
-* [y-dat](http://github.com/y-js/y-dat)
-
-
-### Shared Types
-
-# Table of Contents
-
-* [Getting Started](#Getting-Started)
-  * [Tutorial](#Short-Tutorial)
-* [Providers](#Providers)
-  * [Websocket](#Websocket)
-  * [Ydb](#Ydb)
-  * [Create a Custom Provider](#Create-a-Custom-Provider)
-* [Shared Types](#Shared-Types)
-  * [YArray](#Yarray)
-  * [YMap](#YMap)
-  * [YText](#YText)
-  * [YXmlFragment and YXmlElement](#YXmlFragment-and-YXmlElement)
-  * [Create a Custom Type](#Create-a-Custom-Type)
-* [Bindings](#Bindings)
-  * [PromeMirror](#ProseMirror)
-  * [Quill](#Quill)
-  * [CodeMirror](#CodeMirror)
-  * [Ace](#Ace)
-  * [Monaco](#Monace)
-  * [DOM](#DOM)
-  * [Textarea](#Textarea)
-  * [Create a Custom Binding](#Create-a-Custom-Binding)
-* [Transaction](#Transaction)
-* [Offline Editing](#Offline-Editing)
-* [Awareness](#Awareness)
-* [Working with Yjs](#Working-with-Yjs)
-  * [Typescript Declarations](#Typescript-Declarations)
-* [Binary Protocols](#Binary-Protocols)
-  * [Sync Protocol](#Sync-Protocols)
-  * [Awareness Protocol](#Awareness-Protocols)
-  * [Auth Protocol](#Auth-Protocol)
-* [Yjs CRDT Algorithm](#Yjs-CRDT-Algorithm)
-* [Evaluation](#Evaluation)
-  * [Existing shared editing libraries](#Exisisting-Javascript-Products)
-  * [CRDT Algorithms](#CRDT-Algorithms)
-  * [Comparison of CRDT with OT](#Comparing-CRDT-with-OT)
-  * [Comparison of CRDT Algorithms](#Comparing-CRDT-Algorithms)
-  * [Comparison of Yjs with other Implementations](#Comparing-Yjs-with-other-Implementations)
-* [License and Author](#License-and-Author)
-
-## Getting Started
-
-Yjs does not hava any dependencies. Install this package with your favorite package manager, or just copy the files into your project.
-
-```sh
-npm i yjs
-```
-
-##### Quickstart
-
-Yjs itself only knows how to do conflict resolution. You need to choose a provider, that handles how document updates are distributed over the network.
-
-We will start by running a websocket server (part of the [websocket provider](#Websocket-Provider)):
-
-```sh
-PORT=1234 node ./node_modules/yjs/provider/websocket/server.js
-```
-
-The following client-side code connects to the websocket server and opens a shared document.
-
-```js
-import * as Y from 'yjs'
-import { WebsocketProvider } from 'yjs/provider/websocket.js'
-
-const provider = new WebsocketProvider('http://localhost:1234')
-const sharedDocument = provider.get('my-favourites')
-```
-
-All content created in a shared document is shared among all peers that request the same document. Now we define types on the shared document:
-
-```js
-sharedDocument.define('movie-ratings', Y.Map)
-sharedDocument.define('favourite-food', Y.Array)
-```
-
-All clients that define `'movie-ratings'` as `Y.Map` on the shared document named `'my-favourites'` have access to the same shared type. Example:
-
-**Client 1:**
-
-```js
-sharedDocument.define('movie-ratings', Y.Map)
-sharedDocument.define('favourite-food', Y.Array)
-
-const movies = sharedDocument.get('movie-ratings')
-const food = sharedDocument.get('fovourite-food')
-
-movies.set('deadpool', 10)
-food.insert(0, ['burger'])
-```
-
-**Client 2:**
-
-```js
-sharedDocument.define('movie-ratings', Y.Map)
-sharedDocument.define('favourite-food', Y.Map) // <- note that this definition differs from client1
-
-const movies = sharedDocument.get('movie-ratings')
-const food = sharedDocument.get('fovourite-food')
-
-movies.set('yt rewind', -10)
-food.set('pancake', 10)
-
-// after some time, when client1 and client2 synced, the movie list will be merged:
-movies.toJSON() // => { 'deadpool': 10, 'yt rewind': -10 }
-
-// But since client1 and client2 defined the types differently,
-// they do not have access to each others food list.
-food.toJSON() // => { pancake: 10 }
-```
-
-Now you understand how types are defined on a shared document. Next you can jump to one of the [tutorials on our website](https://yjs.website/tutorial-prosemirror.html) or continue reading about [Providers](#Providers), [Shared Types](#Shared-Types), and [Bindings](#Bindings).
-
-## API
-
-## Providers
-
-In Yjs, a provider handles the communication channel to *authenticate*, *authorize*, and *exchange document updates*. Yjs ships with some existing providers. 
-
-### Websocket Provider
-
-The websocket provider implements a classical client server model. Clients connect to a single endpoint over websocket. The server distributes awareness information and document updates among clients.
-
-The Websocket Provider is a solid choice if you want a central source that handles authentication and authorization. Websockets also send header information and cookies, so you can use existing authentication mechanisms with this server. I recommend that you slightly adapt the server in `./provider/websocket/server.js` to your needs.
-
-* Supports cross-tab communication. When you open the same document in the same browser, changes on the document are exchanged via cross-tab communication ([Broadcast Channel](https://developer.mozilla.org/en-US/docs/Web/API/Broadcast_Channel_API) and [localStorage](https://developer.mozilla.org/en-US/docs/Web/API/Window/localStorage) as fallback).
-* Supports exange of awareness information (e.g. cursors)
-
-##### Start a Websocket Server:
-
-```sh
-PORT=1234 node ./node_modules/yjs/provider/websocket/server.js
-```
-
-**Websocket Server with Persistence**
-
-Persist document updates in a LevelDB database.
-
-See [LevelDB Persistence](#LevelDB Persistence) for more info.
-
-```sh
-PORT=1234 YPERSISTENCE=./dbDir node ./node_modules/yjs/provider/websocket/server.js
-```
-
-##### Client Code:
-
-```js
-import * as Y from 'yjs'
-import { WebsocketProvider } from 'yjs/provider/websocket.js'
-
-const provider = new WebsocketProvider('http://localhost:1234')
-
-// open a websocket connection to http://localhost:1234/my-document-name
-const sharedDocument = provider.get('my-document-name')
-
-sharedDocument.on('status', event => {
-  console.log(event.status) // logs "connected" or "disconnected"
-})
-```
-
-#### Scaling
-
-These are mere suggestions how you could scale your server environment.
-
-**Option 1:** Websocket servers communicate with each other via a PubSub server. A room is represented by a PubSub channel. The downside of this approach is that the same shared document may be handled by many servers. But the upside is that this approach is fault tolerant, does not have a single point of failure, and is perfectly fit for route balancing.
-
-**Option 2:** Sharding with *consistent hashing*. Each document is handled by a unique server. This patterns requires an entity, like etcd, that performs regular health checks and manages servers. Based on the list of available servers (which is managed by etcd) a proxy calculates which server is responsible for each requested document. The disadvantage of this approach is that it is that load distribution may not be fair. Still, this approach may be the preferred solution if you want to store the shared document in a database - e.g. for indexing.
-
-### Ydb Provider
-
-TODO
-
-### Create Custom Provider
-
-A provider is only a concept. I encourage you to implement the same provider interface found above. This makes it easy to exchange communication protocols.
-
-Since providers handle the communication channel, they will necessarily interact with the [binary protocols](#Binary-Protocols). I suggest that you build upon the existing protocols. But you may also implement a custom communication protocol.
-
-Read section [Sync Protocol](#Sync-Protocol) to learn how syncing works.
-
-## Shared Types
-
-A shared type is just a normal data type like [Map](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Map) or [Array](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Array). But a shared type may also be modified by a remote client. Conflicts are automatically resolved by the rules described in this section - but please note that this is only a rough overview of how conflict resolution works. Please read the [Yjs CRDT Algorithm](#Yjs-CRDT-Algorithm) section for an in-depth description of the conflict resolution approach.
-
-As explained in [Tutorial](#Tutorial), a shared type is shared among all peers when they are defined with the same name on the same shared document. I.e.
-
-```js
-sharedDocument.define('my-array', Y.Array)
-
-const myArray = sharedDocument.get('my-array')
-```
-
-You may define a shared types several times, as long as you don't change the type definition.
-
-```js
-sharedDocument.define('my-array', Y.Array)
-
-const myArray = sharedDocument.get('my-array')
-
-const alsoMyArray = sharedDocument.define('my-array', Y.Array)
-
-console.log(myArray === alsoMyArray) // => true
-```
-
-All shared types have an `type.observe(event => ..)` method that allows you to observe any changes. You may also observe all changes on a type and any of its children with the `type.observeDeep(events => ..)` method. Here, `events` is the [Set](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Set) of events that were fired on type, or any of its children.
-
-All Events inherit from [YEvent](https://yjs.website/module-utils.YEvent.html).
-
-### YMap
-> Complete API docs: [https://yjs.website/module-types.ymap](https://yjs.website/module-types.ymap)
-
-The YMap type is very similar to the JavaScript [Map](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Map). 
-
-YMap fires [YMapEvents](https://yjs.website/module-types.YMapEvent.html).
-
-```js
-import * as Y from 'yjs'
-
-const ymap = new Y.Map()
-
-ymap.observe(event => {
-  console.log('ymap keys changed:', event.keysChanged, event.remote)
-})
-
-ymap.set('key', 'value') // => ymap keys changed: Set{ 'key' } false
-ymap.delete('key') // => ymap keys changed: Set{ 'key' }
-
-const ymap2 = new YMap()
-ymap2.set(1, 'two')
-
-ymap.set('type', ymap2) // => ymap keys changed: Set{ 'type' }
-```
-
-##### Concurrent YMap changes
-
-* Concurrent edits on different keys do not affect each other. E.g. if client1 does `ymap.set('a', 1)` and client2 does `ymap.set('b', 2)`, both clients will end up with `YMap{ a: 1, b: 2 }`
-* If client1 and client2 `set` the same property at the same time, the edit from the client with the smaller userID will prevail (`sharedDocument.userID`)
-* If client1 sets a property `ymap.set('a', 1)` and client2 deletes a property `ymap.delete('a')`, the set operation always prevails.
-
-### YArray
-> Complete API docs: [https://yjs.website/module-types.yarray](https://yjs.website/module-types.yarray)
-
-YArray fires [YArrayEvents](https://yjs.website/module-types.YMapEvent.html).
-
-
-```js
-import * as Y from 'yjs'
-
-const yarray = new Y.Array()
-
-yarray.observe(event => {
-  console.log('yarray changed:', event.addedElements, event.removedElements, event.remote)
-})
-
-// insert two elements at position 0
-yarray.insert(0, ['a', 1]) // => yarray changed: Set{Item{'a'}, Item{1}}, Set{}, false 
-console.log(yarray.toArray()) // => ['a', 1]
-yarray.delete(1, 1) // yarray changed: Set{}, Set{Item{1}}, false
-
-yarray.insert(1, new Y.Map()) // => yarray changed: Set{YMap{}}, Set{}, false
-
-// The difference between .toArray and .toJSON:
-console.log(yarray.toArray()) // => ['a', YMap{}]
-console.log(yarray.toJSON()) // => ['a', {}]
-```
-
-As you can see from the above example, primitive data is wrapped into an Item. This makes it possible to find the exact location of the change.
-
-##### Concurrent YArray changes
-
-* YArray internally represents the data as a doubly linked list. The Array `['a', YMap{}, 1]` is internally represented as `Item{'a'} <-> YMap{} <-> Item{1}`. Accordingly, the insert operation `yarray.insert(1, ['b'])` is internally transformed to `insert Item{'b'} between Item{'a'} and YMap{}`.
-* When an Item is deleted, it is only marked as deleted. Only its content is garbage collected and freed from memory.
-* Therefore, the remote operation `insert x between a and b` can still be fulfilled when item `a` or item `b` are deleted.
-* In case that two clients insert content between the same items (a concurrent insertion), the order of the insertions is decided based on the `sharedDocument.userID`.
-
-### YText
-> Complete API docs: [https://yjs.website/module-types.ytext](https://yjs.website/module-types.ytext)
-
-A YText is basically a [YArray](#YArray) that is optimized for text content. 
-
-### YXmlFragment and YXmlElement
-> Complete API docs: [https://yjs.website/module-types.yxmlfragment](https://yjs.website/module-types.yxmlfragment) and [https://yjs.website/module-types.yxmlelement](https://yjs.website/module-types.yxmlelement)
-
-### Custom Types
-
-## Bindings
-
-## Transaction
-
-
-
-## Binary Protocols
-
-### Sync Protocol
-
-Sync steps
-
-### Awareness Protocol
-
-### Auth Protocol
-
-## Offline Editing
-
-It is trivial with Yjs to persist the local state to indexeddb, so it is always available when working offline. But there are two non-trivial questions that need to answered when implementing a professional offline editing app:
-
-1. How does a client sync down all rooms that were modified while offline?
-2. How does a client sync up all rooms that were modified while offline?
-
-Assuming 5000 documents are stored on each client for offline usage. How do we sync up/down each of those documents after a client comes online? It would be inefficient to sync each of those rooms separately. The only provider that currently supports syncing many rooms efficiently is Ydb, because its database layer is optimized to sync many rooms with each client.
-
-If you do not care about 1. and 2. you can use `/persistences/indexeddb.js` to mirror the local state to indexeddb.
-
-## Working with Yjs
-
-### Typescript Declarations
-
-Until [this](https://github.com/Microsoft/TypeScript/issues/7546) is fixed, the only way to get type declarations is by adding Yjs to the list of checked files:
-
-```json
-{
-  "compilerOptions": {
-    "allowJs": true,
-    "checkJs": true,
-    ..
-  },
-  "maxNodeModuleJsDepth": 5
-}
-```
-
-## CRDT Algorithm
-
-## License and Author
-
-Yjs and all related projects are [**MIT licensed**](./LICENSE). Some files also contain an additional copyright notice that allows you to copy and modify the code without shipping the copyright notice (e.g. `./provider/websocket/WebsocketProvider.js` and `./provider/websocket/server.js`)
-
-Yjs is based on the research I did as a student at the RWTH i5. I am working on Yjs in my spare time. Please help me by donating or hiring me for consulting, so I can continue to work on this project.
-
-kevin.jahns@protonmail.com

examples/.gitignore

@@ -1 +0,0 @@
-build

examples/codemirror.html

@@ -1,70 +0,0 @@
-<!DOCTYPE html>
-<html>
-<head>
-    <title>Yjs CodeMirror Example</title>
-    <link rel=stylesheet href="https://codemirror.net/lib/codemirror.css">
-    <style>
-      #container {
-        border: grey;
-        border-style: solid;
-        border-width: thin;
-      }
-    </style>
-  </head>
-<body>
-  <p>This example shows how to bind a YText type to <a href="https://codemirror.net/">CodeMirror</a> editor.</p>
-  <p>The content of this editor is shared with every client who visits this domain.</p>
-  <div class="code-html">
-<style>
-.remote-caret {
-  position: absolute;
-  border-left: black;
-  border-left-style: solid;
-  border-left-width: 2px;
-  height: 1em;
-}
-.remote-caret > div {
-  position: relative;
-  top: -1.05em;
-  font-size: 13px;
-  background-color: rgb(250, 129, 0);
-  font-family: serif;
-  font-style: normal;
-  font-weight: normal;
-  line-height: normal;
-  user-select: none;
-  color: white;
-  padding-left: 2px;
-  padding-right: 2px;
-}
-</style>
-<div id="container"></div>
-  </div>
-  <!-- The actual source file for the following code is found in ./codemirror.js. Run `npm run watch` to compile the files -->
-  <script class="code-js" src="./build/codemirror.js" type="module">
-import * as Y from 'yjs'
-import { WebsocketProvider } from 'yjs/provider/websocket.js'
-import { CodeMirrorBinding } from 'yjs/bindings/codemirror.js'
-
-import * as conf from './exampleConfig.js'
-
-import CodeMirror from 'codemirror'
-import 'codemirror/mode/javascript/javascript.js'
-
-const provider = new WebsocketProvider(conf.serverAddress)
-const ydocument = provider.get('codemirror')
-const ytext = ydocument.define('codemirror', Y.Text)
-
-const editor = new CodeMirror(document.querySelector('#container'), {
-    mode: 'javascript',
-    lineNumbers: true
-})
-
-const binding = new CodeMirrorBinding(ytext, editor)
-
-window.codemirrorExample = {
-  binding, editor, ytext, ydocument
-}
-  </script>
-</body>
-</html>

examples/codemirror.js

@@ -1,22 +0,0 @@
-import { WebsocketProvider } from 'y-websocket'
-import { CodeMirrorBinding } from 'y-codemirror'
-
-import * as conf from './exampleConfig.js'
-
-import CodeMirror from 'codemirror'
-import 'codemirror/mode/javascript/javascript.js'
-
-const provider = new WebsocketProvider(conf.serverAddress)
-const ydocument = provider.get('codemirror')
-const ytext = ydocument.getText('codemirror')
-
-const editor = new CodeMirror(document.querySelector('#container'), {
-  mode: 'javascript',
-  lineNumbers: true
-})
-
-const binding = new CodeMirrorBinding(ytext, editor)
-
-window.codemirrorExample = {
-  binding, editor, ytext, ydocument
-}

examples/dom.html

@@ -1,37 +0,0 @@
-<!DOCTYPE html>
-<html>
-<head>
-    <title>Yjs Prosemirror Example</title>
-    <link rel=stylesheet href="https://prosemirror.net/css/editor.css">
-    <style>
-      #content {
-        min-height: 500px;
-      }
-    </style>
-</head>
-<body>
-  <p>This example shows how to bind a YXmlFragment type to an arbitrary DOM element. We set the DOM element to contenteditable so it basically behaves like a very powerful rich-text editor.</p>
-  <p>The content of this editor is shared with every client who visits this domain.</p>
-  <hr>
-  <div class="code-html">
-
-<div id="content" contenteditable=""></div>
-  </div>
-  <!-- The actual source file for the following code is found in ./dom.js. Run `npm run watch` to compile the files -->
-  <script class="code-js" src="./build/dom.js" type="module">
-    import * as Y from 'yjs/index.js'
-    import { WebsocketProvider } from 'yjs/provider/websocket.js'
-    import { DomBinding } from 'yjs/bindings/dom.js'
-    import * as conf from './exampleConfig.js'
-
-    const provider = new WebsocketProvider(conf.serverAddress)
-    const ydocument = provider.get('dom')
-    const type = ydocument.define('xml', Y.XmlFragment)
-    const binding = new DomBinding(type, document.querySelector('#content'), { scrollingElement: document.scrollingElement })
-
-    window.example = {
-      provider, ydocument, type, binding
-    }
-  </script>
-</body>
-</html>

examples/dom.js

@@ -1,13 +0,0 @@
-import * as Y from '../src/index.js'
-import { WebsocketProvider } from 'y-websocket'
-import { DomBinding } from 'y-dom'
-import * as conf from './exampleConfig.js'
-
-const provider = new WebsocketProvider(conf.serverAddress)
-const ydocument = provider.get('dom')
-const type = ydocument.define('xml', Y.XmlFragment)
-const binding = new DomBinding(type, document.querySelector('#content'), { scrollingElement: document.scrollingElement })
-
-window.example = {
-  provider, ydocument, type, binding
-}

examples/exampleConfig.js

@@ -1,9 +0,0 @@
-/* eslint-env browser */
-
-const isDeployed = location.hostname === 'yjs.website'
-
-if (!isDeployed) {
-  console.log('%cYjs: Start your local websocket server by running %c`npm run websocket-server`', 'color:blue', 'color: grey; font-weight: bold')
-}
-
-export const serverAddress = isDeployed ? 'wss://api.yjs.website' : 'ws://localhost:1234'

examples/examples.json

@@ -1,17 +0,0 @@
-{
-  "codemirror": {
-    "title": "CodeMirror Binding"
-  },
-  "prosemirror": {
-    "title": "ProseMirror Binding"
-  },
-  "textarea": {
-    "title": "Textarea Binding"
-  },
-  "quill": {
-    "title": "Quill Binding"
-  },
-  "dom": {
-    "title": "Dom Binding"
-  }
-}

examples/prosemirror-history.js

@@ -1,159 +0,0 @@
-
-import { Plugin } from 'prosemirror-state'
-import crel from 'crel'
-import * as Y from '../src/index.js'
-import { prosemirrorPluginKey } from 'y-prosemirror'
-import * as encoding from 'lib0/encoding.js'
-import * as decoding from 'lib0/decoding.js'
-import * as historyProtocol from 'y-protocols/history.js'
-
-const niceColors = ['#3cb44b', '#4363d8', '#f58231', '#911eb4', '#46f0f0', '#f032e6', '#bcf60c', '#008080', '#9a6324', '#800000', '#808000', '#000075', '#808080']
-
-const createUserCSS = (userid, username, color = 'rgb(250, 129, 0)', color2 = 'rgba(250, 129, 0, .41)') => `
-  [ychange_state][ychange_user="${userid}"]:hover::before {
-    content: "${username}" !important;
-    background-color: ${color} !important;
-  }
-  [ychange_state="added"][ychange_user="${userid}"] {
-    background-color: ${color2} !important;
-  }
-  [ychange_state="removed"][ychange_user="${userid}"] {
-    color: ${color} !important;
-  }
-`
-
-export const noteHistoryPlugin = new Plugin({
-  state: {
-    init (initargs, state) {
-      return new NoteHistoryPlugin()
-    },
-    apply (tr, pluginState) {
-      return pluginState
-    }
-  },
-  view (editorView) {
-    const hstate = noteHistoryPlugin.getState(editorView.state)
-    hstate.init(editorView)
-    return {
-      destroy: hstate.destroy.bind(hstate)
-    }
-  }
-})
-
-const createWrapper = () => {
-  const wrapper = crel('div', { style: 'display: flex;' })
-  const historyContainer = crel('div', { style: 'align-self: baseline; flex-basis: 250px;', class: 'shared-history' })
-  wrapper.insertBefore(historyContainer, null)
-  const userStyleContainer = crel('style')
-  wrapper.insertBefore(userStyleContainer, null)
-  return { wrapper, historyContainer, userStyleContainer }
-}
-
-class NoteHistoryPlugin {
-  init (editorView) {
-    this.editorView = editorView
-    const { historyContainer, wrapper, userStyleContainer } = createWrapper()
-    this.userStyleContainer = userStyleContainer
-    this.wrapper = wrapper
-    this.historyContainer = historyContainer
-    const n = editorView.dom.parentNode.parentNode
-    n.parentNode.replaceChild(this.wrapper, n)
-    n.style['flex-grow'] = '1'
-    wrapper.insertBefore(n, this.wrapper.firstChild)
-    this.render()
-    const y = prosemirrorPluginKey.getState(this.editorView.state).y
-    const history = y.define('history', Y.Array)
-    history.observe(this.render.bind(this))
-  }
-  destroy () {
-    this.wrapper.parentNode.replaceChild(this.wrapper.firstChild, this.wrapper)
-    const y = prosemirrorPluginKey.getState(this.editorView.state).y
-    const history = y.define('history', Y.Array)
-    history.unobserve(this.render)
-  }
-  render () {
-    const y = prosemirrorPluginKey.getState(this.editorView.state).y
-    const history = y.define('history', Y.Array).toArray()
-    const fragment = document.createDocumentFragment()
-    const snapshotBtn = crel('button', { type: 'button' }, ['snapshot'])
-    fragment.insertBefore(snapshotBtn, null)
-    let _prevSnap = null // empty
-    snapshotBtn.addEventListener('click', () => {
-      const awareness = y.getAwarenessInfo()
-      const userMap = new Map()
-      const aw = y.getLocalAwarenessInfo()
-      userMap.set(y.userID, aw.name || 'unknown')
-      awareness.forEach((a, userID) => {
-        userMap.set(userID, a.name || 'Unknown')
-      })
-      this.snapshot(userMap)
-    })
-    history.forEach(buf => {
-      const decoder = decoding.createDecoder(buf)
-      const snapshot = historyProtocol.readHistorySnapshot(decoder)
-      const date = new Date(decoding.readUint32(decoder) * 1000)
-      const restoreBtn = crel('button', { type: 'button' }, ['restore'])
-      const a = crel('a', [
-        '• ' + date.toUTCString(), restoreBtn
-      ])
-      const el = crel('div', [ a ])
-      let prevSnapshot = _prevSnap // rebind to new variable
-      restoreBtn.addEventListener('click', event => {
-        if (prevSnapshot === null) {
-          prevSnapshot = { ds: snapshot.ds, sm: new Map() }
-        }
-        this.editorView.dispatch(this.editorView.state.tr.setMeta(prosemirrorPluginKey, { snapshot, prevSnapshot, restore: true }))
-        event.stopPropagation()
-      })
-      a.addEventListener('click', () => {
-        console.log('setting snapshot')
-        if (prevSnapshot === null) {
-          prevSnapshot = { ds: snapshot.ds, sm: new Map() }
-        }
-        this.renderSnapshot(snapshot, prevSnapshot)
-      })
-      fragment.insertBefore(el, null)
-      _prevSnap = snapshot
-    })
-    this.historyContainer.innerHTML = ''
-    this.historyContainer.insertBefore(fragment, null)
-  }
-  renderSnapshot (snapshot, prevSnapshot) {
-    this.editorView.dispatch(this.editorView.state.tr.setMeta(prosemirrorPluginKey, { snapshot, prevSnapshot }))
-    /**
-     * @type {Array<string|null>}
-     */
-    let colors = niceColors.slice()
-    let style = ''
-    snapshot.userMap.forEach((name, userid) => {
-      /**
-       * @type {any}
-       */
-      const randInt = name.split('').map(s => s.charCodeAt(0)).reduce((a, b) => a + b)
-      let color = null
-      let i = 0
-      for (; i < colors.length && color === null; i++) {
-        color = colors[(randInt + i) % colors.length]
-      }
-      if (color === null) {
-        colors = niceColors.slice()
-        i = 0
-        color = colors[randInt % colors.length]
-      }
-      colors[randInt % colors.length] = null
-      style += createUserCSS(userid, name, color, color + '69')
-    })
-    this.userStyleContainer.innerHTML = style
-  }
-  /**
-   * @param {Map<number, string>} [updatedUserMap] Maps from userid (yjs model) to account name (e.g. mail address)
-   */
-  snapshot (updatedUserMap = new Map()) {
-    const y = prosemirrorPluginKey.getState(this.editorView.state).y
-    const history = y.define('history', Y.Array)
-    const encoder = encoding.createEncoder()
-    historyProtocol.writeHistorySnapshot(encoder, y, updatedUserMap)
-    encoding.writeUint32(encoder, Math.floor(Date.now() / 1000))
-    history.push([encoding.toBuffer(encoder)])
-  }
-}

examples/prosemirror-schema.js

@@ -1,197 +0,0 @@
-import { Schema } from 'prosemirror-model'
-
-const brDOM = ['br']
-
-const calcYchangeDomAttrs = (attrs, domAttrs = {}) => {
-  domAttrs = Object.assign({}, domAttrs)
-  if (attrs.ychange !== null) {
-    domAttrs.ychange_user = attrs.ychange.user
-    domAttrs.ychange_state = attrs.ychange.state
-  }
-  return domAttrs
-}
-
-// :: Object
-// [Specs](#model.NodeSpec) for the nodes defined in this schema.
-export const nodes = {
-  // :: NodeSpec The top level document node.
-  doc: {
-    content: 'block+'
-  },
-
-  // :: NodeSpec A plain paragraph textblock. Represented in the DOM
-  // as a `<p>` element.
-  paragraph: {
-    attrs: { ychange: { default: null } },
-    content: 'inline*',
-    group: 'block',
-    parseDOM: [{ tag: 'p' }],
-    toDOM (node) { return ['p', calcYchangeDomAttrs(node.attrs), 0] }
-  },
-
-  // :: NodeSpec A blockquote (`<blockquote>`) wrapping one or more blocks.
-  blockquote: {
-    attrs: { ychange: { default: null } },
-    content: 'block+',
-    group: 'block',
-    defining: true,
-    parseDOM: [{ tag: 'blockquote' }],
-    toDOM (node) { return ['blockquote', calcYchangeDomAttrs(node.attrs), 0] }
-  },
-
-  // :: NodeSpec A horizontal rule (`<hr>`).
-  horizontal_rule: {
-    attrs: { ychange: { default: null } },
-    group: 'block',
-    parseDOM: [{ tag: 'hr' }],
-    toDOM (node) {
-      return ['hr', calcYchangeDomAttrs(node.attrs)]
-    }
-  },
-
-  // :: NodeSpec A heading textblock, with a `level` attribute that
-  // should hold the number 1 to 6. Parsed and serialized as `<h1>` to
-  // `<h6>` elements.
-  heading: {
-    attrs: {
-      level: { default: 1 },
-      ychange: { default: null }
-    },
-    content: 'inline*',
-    group: 'block',
-    defining: true,
-    parseDOM: [{ tag: 'h1', attrs: { level: 1 } },
-      { tag: 'h2', attrs: { level: 2 } },
-      { tag: 'h3', attrs: { level: 3 } },
-      { tag: 'h4', attrs: { level: 4 } },
-      { tag: 'h5', attrs: { level: 5 } },
-      { tag: 'h6', attrs: { level: 6 } }],
-    toDOM (node) { return ['h' + node.attrs.level, calcYchangeDomAttrs(node.attrs), 0] }
-  },
-
-  // :: NodeSpec A code listing. Disallows marks or non-text inline
-  // nodes by default. Represented as a `<pre>` element with a
-  // `<code>` element inside of it.
-  code_block: {
-    attrs: { ychange: { default: null } },
-    content: 'text*',
-    marks: '',
-    group: 'block',
-    code: true,
-    defining: true,
-    parseDOM: [{ tag: 'pre', preserveWhitespace: 'full' }],
-    toDOM (node) { return ['pre', calcYchangeDomAttrs(node.attrs), ['code', 0]] }
-  },
-
-  // :: NodeSpec The text node.
-  text: {
-    group: 'inline'
-  },
-
-  // :: NodeSpec An inline image (`<img>`) node. Supports `src`,
-  // `alt`, and `href` attributes. The latter two default to the empty
-  // string.
-  image: {
-    inline: true,
-    attrs: {
-      ychange: { default: null },
-      src: {},
-      alt: { default: null },
-      title: { default: null }
-    },
-    group: 'inline',
-    draggable: true,
-    parseDOM: [{ tag: 'img[src]',
-      getAttrs (dom) {
-        return {
-          src: dom.getAttribute('src'),
-          title: dom.getAttribute('title'),
-          alt: dom.getAttribute('alt')
-        }
-      } }],
-    toDOM (node) {
-      const domAttrs = {
-        src: node.attrs.src,
-        title: node.attrs.title,
-        alt: node.attrs.alt
-      }
-      return ['img', calcYchangeDomAttrs(node.attrs, domAttrs)]
-    }
-  },
-
-  // :: NodeSpec A hard line break, represented in the DOM as `<br>`.
-  hard_break: {
-    inline: true,
-    group: 'inline',
-    selectable: false,
-    parseDOM: [{ tag: 'br' }],
-    toDOM () { return brDOM }
-  }
-}
-
-const emDOM = ['em', 0]; const strongDOM = ['strong', 0]; const codeDOM = ['code', 0]
-
-// :: Object [Specs](#model.MarkSpec) for the marks in the schema.
-export const marks = {
-  // :: MarkSpec A link. Has `href` and `title` attributes. `title`
-  // defaults to the empty string. Rendered and parsed as an `<a>`
-  // element.
-  link: {
-    attrs: {
-      href: {},
-      title: { default: null }
-    },
-    inclusive: false,
-    parseDOM: [{ tag: 'a[href]',
-      getAttrs (dom) {
-        return { href: dom.getAttribute('href'), title: dom.getAttribute('title') }
-      } }],
-    toDOM (node) { return ['a', node.attrs, 0] }
-  },
-
-  // :: MarkSpec An emphasis mark. Rendered as an `<em>` element.
-  // Has parse rules that also match `<i>` and `font-style: italic`.
-  em: {
-    parseDOM: [{ tag: 'i' }, { tag: 'em' }, { style: 'font-style=italic' }],
-    toDOM () { return emDOM }
-  },
-
-  // :: MarkSpec A strong mark. Rendered as `<strong>`, parse rules
-  // also match `<b>` and `font-weight: bold`.
-  strong: {
-    parseDOM: [{ tag: 'strong' },
-      // This works around a Google Docs misbehavior where
-      // pasted content will be inexplicably wrapped in `<b>`
-      // tags with a font-weight normal.
-      { tag: 'b', getAttrs: node => node.style.fontWeight !== 'normal' && null },
-      { style: 'font-weight', getAttrs: value => /^(bold(er)?|[5-9]\d{2,})$/.test(value) && null }],
-    toDOM () { return strongDOM }
-  },
-
-  // :: MarkSpec Code font mark. Represented as a `<code>` element.
-  code: {
-    parseDOM: [{ tag: 'code' }],
-    toDOM () { return codeDOM }
-  },
-  ychange: {
-    attrs: {
-      user: { default: null },
-      state: { default: null }
-    },
-    inclusive: false,
-    parseDOM: [{ tag: 'ychange' }],
-    toDOM (node) {
-      return ['ychange', { ychange_user: node.attrs.user, ychange_state: node.attrs.state }, 0]
-    }
-  }
-}
-
-// :: Schema
-// This schema rougly corresponds to the document schema used by
-// [CommonMark](http://commonmark.org/), minus the list elements,
-// which are defined in the [`prosemirror-schema-list`](#schema-list)
-// module.
-//
-// To reuse elements from this schema, extend or read from its
-// `spec.nodes` and `spec.marks` [properties](#model.Schema.spec).
-export const schema = new Schema({ nodes, marks })

examples/prosemirror.css

@@ -1,330 +0,0 @@
-.ProseMirror {
-  position: relative;
-}
-
-.ProseMirror {
-  word-wrap: break-word;
-  white-space: pre-wrap;
-  -webkit-font-variant-ligatures: none;
-  font-variant-ligatures: none;
-}
-
-.ProseMirror pre {
-  white-space: pre-wrap;
-}
-
-.ProseMirror li {
-  position: relative;
-}
-
-.ProseMirror-hideselection *::selection { background: transparent; }
-.ProseMirror-hideselection *::-moz-selection { background: transparent; }
-.ProseMirror-hideselection { caret-color: transparent; }
-
-.ProseMirror-selectednode {
-  outline: 2px solid #8cf;
-}
-
-/* Make sure li selections wrap around markers */
-
-li.ProseMirror-selectednode {
-  outline: none;
-}
-
-li.ProseMirror-selectednode:after {
-  content: "";
-  position: absolute;
-  left: -32px;
-  right: -2px; top: -2px; bottom: -2px;
-  border: 2px solid #8cf;
-  pointer-events: none;
-}
-.ProseMirror-textblock-dropdown {
-  min-width: 3em;
-}
-
-.ProseMirror-menu {
-  margin: 0 -4px;
-  line-height: 1;
-}
-
-.ProseMirror-tooltip .ProseMirror-menu {
-  width: -webkit-fit-content;
-  width: fit-content;
-  white-space: pre;
-}
-
-.ProseMirror-menuitem {
-  margin-right: 3px;
-  display: inline-block;
-}
-
-.ProseMirror-menuseparator {
-  border-right: 1px solid #ddd;
-  margin-right: 3px;
-}
-
-.ProseMirror-menu-dropdown, .ProseMirror-menu-dropdown-menu {
-  font-size: 90%;
-  white-space: nowrap;
-}
-
-.ProseMirror-menu-dropdown {
-  vertical-align: 1px;
-  cursor: pointer;
-  position: relative;
-  padding-right: 15px;
-}
-
-.ProseMirror-menu-dropdown-wrap {
-  padding: 1px 0 1px 4px;
-  display: inline-block;
-  position: relative;
-}
-
-.ProseMirror-menu-dropdown:after {
-  content: "";
-  border-left: 4px solid transparent;
-  border-right: 4px solid transparent;
-  border-top: 4px solid currentColor;
-  opacity: .6;
-  position: absolute;
-  right: 4px;
-  top: calc(50% - 2px);
-}
-
-.ProseMirror-menu-dropdown-menu, .ProseMirror-menu-submenu {
-  position: absolute;
-  background: white;
-  color: #666;
-  border: 1px solid #aaa;
-  padding: 2px;
-}
-
-.ProseMirror-menu-dropdown-menu {
-  z-index: 15;
-  min-width: 6em;
-}
-
-.ProseMirror-menu-dropdown-item {
-  cursor: pointer;
-  padding: 2px 8px 2px 4px;
-}
-
-.ProseMirror-menu-dropdown-item:hover {
-  background: #f2f2f2;
-}
-
-.ProseMirror-menu-submenu-wrap {
-  position: relative;
-  margin-right: -4px;
-}
-
-.ProseMirror-menu-submenu-label:after {
-  content: "";
-  border-top: 4px solid transparent;
-  border-bottom: 4px solid transparent;
-  border-left: 4px solid currentColor;
-  opacity: .6;
-  position: absolute;
-  right: 4px;
-  top: calc(50% - 4px);
-}
-
-.ProseMirror-menu-submenu {
-  display: none;
-  min-width: 4em;
-  left: 100%;
-  top: -3px;
-}
-
-.ProseMirror-menu-active {
-  background: #eee;
-  border-radius: 4px;
-}
-
-.ProseMirror-menu-active {
-  background: #eee;
-  border-radius: 4px;
-}
-
-.ProseMirror-menu-disabled {
-  opacity: .3;
-}
-
-.ProseMirror-menu-submenu-wrap:hover .ProseMirror-menu-submenu, .ProseMirror-menu-submenu-wrap-active .ProseMirror-menu-submenu {
-  display: block;
-}
-
-.ProseMirror-menubar {
-  border-top-left-radius: inherit;
-  border-top-right-radius: inherit;
-  position: relative;
-  min-height: 1em;
-  color: #666;
-  padding: 1px 6px;
-  top: 0; left: 0; right: 0;
-  border-bottom: 1px solid silver;
-  background: white;
-  z-index: 10;
-  -moz-box-sizing: border-box;
-  box-sizing: border-box;
-  overflow: visible;
-}
-
-.ProseMirror-icon {
-  display: inline-block;
-  line-height: .8;
-  vertical-align: -2px; /* Compensate for padding */
-  padding: 2px 8px;
-  cursor: pointer;
-}
-
-.ProseMirror-menu-disabled.ProseMirror-icon {
-  cursor: default;
-}
-
-.ProseMirror-icon svg {
-  fill: currentColor;
-  height: 1em;
-}
-
-.ProseMirror-icon span {
-  vertical-align: text-top;
-}
-.ProseMirror-gapcursor {
-  display: none;
-  pointer-events: none;
-  position: absolute;
-}
-
-.ProseMirror-gapcursor:after {
-  content: "";
-  display: block;
-  position: absolute;
-  top: -2px;
-  width: 20px;
-  border-top: 1px solid black;
-  animation: ProseMirror-cursor-blink 1.1s steps(2, start) infinite;
-}
-
-@keyframes ProseMirror-cursor-blink {
-  to {
-    visibility: hidden;
-  }
-}
-
-.ProseMirror-focused .ProseMirror-gapcursor {
-  display: block;
-}
-/* Add space around the hr to make clicking it easier */
-
-.ProseMirror-example-setup-style hr {
-  padding: 2px 10px;
-  border: none;
-  margin: 1em 0;
-}
-
-.ProseMirror-example-setup-style hr:after {
-  content: "";
-  display: block;
-  height: 1px;
-  background-color: silver;
-  line-height: 2px;
-}
-
-.ProseMirror ul, .ProseMirror ol {
-  padding-left: 30px;
-}
-
-.ProseMirror blockquote {
-  padding-left: 1em;
-  border-left: 3px solid #eee;
-  margin-left: 0; margin-right: 0;
-}
-
-.ProseMirror-example-setup-style img {
-  cursor: default;
-}
-
-.ProseMirror-prompt {
-  background: white;
-  padding: 5px 10px 5px 15px;
-  border: 1px solid silver;
-  position: fixed;
-  border-radius: 3px;
-  z-index: 11;
-  box-shadow: -.5px 2px 5px rgba(0, 0, 0, .2);
-}
-
-.ProseMirror-prompt h5 {
-  margin: 0;
-  font-weight: normal;
-  font-size: 100%;
-  color: #444;
-}
-
-.ProseMirror-prompt input[type="text"],
-.ProseMirror-prompt textarea {
-  background: #eee;
-  border: none;
-  outline: none;
-}
-
-.ProseMirror-prompt input[type="text"] {
-  padding: 0 4px;
-}
-
-.ProseMirror-prompt-close {
-  position: absolute;
-  left: 2px; top: 1px;
-  color: #666;
-  border: none; background: transparent; padding: 0;
-}
-
-.ProseMirror-prompt-close:after {
-  content: "✕";
-  font-size: 12px;
-}
-
-.ProseMirror-invalid {
-  background: #ffc;
-  border: 1px solid #cc7;
-  border-radius: 4px;
-  padding: 5px 10px;
-  position: absolute;
-  min-width: 10em;
-}
-
-.ProseMirror-prompt-buttons {
-  margin-top: 5px;
-  display: none;
-}
-#editor, .editor {
-  background: white;
-  color: black;
-  background-clip: padding-box;
-  border-radius: 4px;
-  border: 2px solid rgba(0, 0, 0, 0.2);
-  padding: 5px 0;
-  margin-bottom: 23px;
-}
-
-.ProseMirror p:first-child,
-.ProseMirror h1:first-child,
-.ProseMirror h2:first-child,
-.ProseMirror h3:first-child,
-.ProseMirror h4:first-child,
-.ProseMirror h5:first-child,
-.ProseMirror h6:first-child {
-  margin-top: 10px;
-}
-
-.ProseMirror {
-  padding: 4px 8px 4px 14px;
-  line-height: 1.2;
-  outline: none;
-}
-
-.ProseMirror p { margin-bottom: 1em }
-

examples/prosemirror.html

@@ -1,117 +0,0 @@
-<!DOCTYPE html>
-<html>
-<head>
-    <title>Yjs Prosemirror Example</title>
-    <link rel=stylesheet href="./prosemirror.css">
-    <style>
-      placeholder {
-        display: inline;
-        border: 1px solid #ccc;
-        color: #ccc;
-      }
-      placeholder:after {
-        content: "☁";
-        font-size: 200%;
-        line-height: 0.1;
-        font-weight: bold;
-      }
-      .ProseMirror img { max-width: 100px }
-      /* this is a rough fix for the first cursor position when the first paragraph is empty */
-      .ProseMirror > .ProseMirror-yjs-cursor:first-child {
-        margin-top: 16px;
-      }
-      .ProseMirror p:first-child, .ProseMirror h1:first-child, .ProseMirror h2:first-child, .ProseMirror h3:first-child, .ProseMirror h4:first-child, .ProseMirror h5:first-child, .ProseMirror h6:first-child {
-        margin-top: 16px
-      }
-      .ProseMirror-yjs-cursor {
-        position: absolute;
-        border-left: black;
-        border-left-style: solid;
-        border-left-width: 2px;
-        border-color: orange;
-        height: 1em;
-        word-break: normal;
-      }
-      .ProseMirror-yjs-cursor > div {
-        position: relative;
-        top: -1.05em;
-        font-size: 13px;
-        background-color: rgb(250, 129, 0);
-        font-family: serif;
-        font-style: normal;
-        font-weight: normal;
-        line-height: normal;
-        user-select: none;
-        color: white;
-        padding-left: 2px;
-        padding-right: 2px;
-      }
-      [ychange_state] {
-        position: relative;
-      }
-      [ychange_state]:hover::before {
-        content: attr(ychange_user);
-        background-color: #fa8100;
-        position: absolute;
-        top: -14px;
-        right: 0;
-        font-size: 12px;
-        padding: 0 2px;
-        border-radius: 3px 3px 0 0;
-        color: #fdfdfe;
-        user-select: none;
-        word-break: normal;
-      }
-      *[ychange_state='added'] {
-        background-color: #fa810069;
-      }
-      ychange[ychange_state='removed'] {
-        color: rgb(250, 129, 0);
-        text-decoration: line-through;
-      }
-      *:not(ychange)[ychange_state='removed'] {
-        background-color: #ff9494c9;
-        text-decoration: line-through;
-      }
-      img[ychange_state='removed'] {
-        padding: 2px;
-      }
-    </style>
-</head>
-<body>
-  <p>This example shows how to bind a YXmlFragment type to a <a href="http://prosemirror.net">Prosemirror</a> editor.</p>
-  <p>The content of this editor is shared with every client who visits this domain.</p>
-  <div class="code-html">
-
-<div id="editor" style="margin-bottom: 23px"></div>
-<div style="display: none" id="content"></div>
-  </div>
-  <!-- The actual source file for the following code is found in ./prosemirror.js. Run `npm run watch` to compile the files -->
-  <script class="code-js" src="./build/prosemirror.js" type="module">
-import * as Y from 'yjs'
-import { WebsocketProvider } from 'yjs/provider/websocket.js'
-import { prosemirrorPlugin, cursorPlugin } from 'yjs/bindings/prosemirror'
-
-import * as conf from './exampleConfig.js'
-
-import { EditorState } from 'prosemirror-state'
-import { EditorView } from 'prosemirror-view'
-import { DOMParser } from 'prosemirror-model'
-import { schema } from 'prosemirror-schema-basic'
-import { exampleSetup } from 'prosemirror-example-setup'
-
-const provider = new WebsocketProvider(conf.serverAddress)
-const ydocument = provider.get('prosemirror')
-const type = ydocument.define('prosemirror', Y.XmlFragment)
-
-const prosemirrorView = new EditorView(document.querySelector('#editor'), {
-  state: EditorState.create({
-    doc: DOMParser.fromSchema(schema).parse(document.querySelector('#content')),
-    plugins: exampleSetup({schema}).concat([prosemirrorPlugin(type), cursorPlugin])
-  })
-})
-
-window.example = { provider, ydocument, type, prosemirrorView }
-  </script>
-</body>
-</html>

examples/prosemirror.js

@@ -1,25 +0,0 @@
-import * as Y from 'yjs'
-import { WebsocketProvider } from 'y-websocket'
-import { prosemirrorPlugin, cursorPlugin } from 'y-prosemirror'
-
-import * as conf from './exampleConfig.js'
-
-import { EditorState } from 'prosemirror-state'
-import { EditorView } from 'prosemirror-view'
-import { DOMParser } from 'prosemirror-model'
-import { schema } from './prosemirror-schema.js'
-import { exampleSetup } from 'prosemirror-example-setup'
-// import { noteHistoryPlugin } from './prosemirror-history.js'
-
-const provider = new WebsocketProvider(conf.serverAddress)
-const ydocument = provider.get('prosemirror', { gc: false })
-const type = ydocument.define('prosemirror', Y.XmlFragment)
-
-const prosemirrorView = new EditorView(document.querySelector('#editor'), {
-  state: EditorState.create({
-    doc: DOMParser.fromSchema(schema).parse(document.querySelector('#content')),
-    plugins: exampleSetup({ schema }).concat([prosemirrorPlugin(type), cursorPlugin])
-  })
-})
-
-window.example = { provider, ydocument, type, prosemirrorView }

examples/quill.html

@@ -1,51 +0,0 @@
-<!DOCTYPE html>
-<html>
-<head>
-    <title>Yjs Quill Example</title>
-    <link rel="stylesheet" href="https://cdn.quilljs.com/1.3.6/quill.snow.css">
-  </head>
-<body>
-  <p>This example shows how to bind a YText type to <a href="https://quilljs.com">Quill</a> editor.</p>
-  <p>The content of this editor is shared with every client who visits this domain.</p>
-  <div class="code-html">
-<div id="quill-container">
-  <div id="quill">
-  </div>
-</div>
-  </div>
-  <!-- The actual source file for the following code is found in ./quill.js. Run `npm run watch` to compile the files -->
-  <script class="code-js" src="./build/quill.js" type="module">
-import * as Y from 'yjs'
-import { WebsocketProvider } from 'yjs/provider/websocket.js'
-import { QuillBinding } from 'yjs/bindings/quill.js'
-
-import * as conf from './exampleConfig.js'
-
-import Quill from 'quill'
-
-const provider = new WebsocketProvider(conf.serverAddress)
-const ydocument = provider.get('quill')
-const ytext = ydocument.define('quill', Y.Text)
-
-const quill = new Quill('#quill-container', {
-  modules: {
-    toolbar: [
-      [{ header: [1, 2, false] }],
-      ['bold', 'italic', 'underline'],
-      ['image', 'code-block'],
-      [{ color: [] }, { background: [] }], // Snow theme fills in values
-      [{ script: 'sub' }, { script: 'super' }],
-      ['link', 'image'],
-      ['link', 'code-block'],
-      [{ list: 'ordered' }, { list: 'bullet' }]
-    ]
-  },
-  placeholder: 'Compose an epic...',
-  theme: 'snow' // or 'bubble'
-})
-
-window.quillBinding = new QuillBinding(ytext, quill)
-
-  </script>
-</body>
-</html>

examples/quill.js

@@ -1,30 +0,0 @@
-import * as Y from '../src/index.js'
-import { WebsocketProvider } from 'y-websocket'
-import { QuillBinding } from 'y-quill'
-
-import * as conf from './exampleConfig.js'
-
-import Quill from 'quill'
-
-const provider = new WebsocketProvider(conf.serverAddress)
-const ydocument = provider.get('quill')
-const ytext = ydocument.define('quill', Y.Text)
-
-const quill = new Quill('#quill-container', {
-  modules: {
-    toolbar: [
-      [{ header: [1, 2, false] }],
-      ['bold', 'italic', 'underline'],
-      ['image', 'code-block'],
-      [{ color: [] }, { background: [] }], // Snow theme fills in values
-      [{ script: 'sub' }, { script: 'super' }],
-      ['link', 'image'],
-      ['link', 'code-block'],
-      [{ list: 'ordered' }, { list: 'bullet' }]
-    ]
-  },
-  placeholder: 'Compose an epic...',
-  theme: 'snow' // or 'bubble'
-})
-
-window.quillBinding = new QuillBinding(ytext, quill)

examples/style.css

@@ -1,29 +0,0 @@
-footer img {
-  display: none;
-}
-
-nav .title h1 a {
-  display: none;
-}
-
-footer {
-  background-color: #b93c1d;
-}
-
-#resizer {
-  background-color: #b93c1d;
-}
-
-.main section article.readme h1:first-child img {
-  display: none;
-}
-
-.main section article.readme h1:first-child {
-  margin-bottom: 16px;
-  margin-top: 30px;
-}
-
-.main section article.readme h1:first-child::before {
-  content: "Yjs";
-  font-size: 2em;
-}

examples/textarea.html

@@ -1,32 +0,0 @@
-<!DOCTYPE html>
-<html>
-<head>
-    <title>Yjs Textarea Example</title>
-</head>
-<body>
-  <p>This example shows how to bind a YText type to a DOM Textarea.</p>
-  <p>The content of this textarea is shared with every client who visits this domain.</p>
-  <div class="code-html">
-
-<textarea style="width:80%;" rows=40 autocomplete="off" autocorrect="off" autocapitalize="off" spellcheck="false"></textarea>
-  </div>
-  <!-- The actual source file for the following code is found in ./textarea.js. Run `npm run watch` to compile the files -->
-  <script class="code-js" src="./build/textarea.js" type="module">
-import * as Y from 'yjs'
-import { WebsocketProvider } from 'yjs/provider/websocket.js'
-import { TextareaBinding } from 'yjs/bindings/textarea.js'
-
-import * as conf from './exampleConfig.js'
-
-const provider = new WebsocketProvider(conf.serverAddress)
-const ydocument = provider.get('textarea')
-const type = ydocument.define('textarea', Y.Text)
-const textarea = document.querySelector('textarea')
-const binding = new TextareaBinding(type, textarea)
-
-window.textareaExample = {
-  provider, ydocument, type, textarea, binding
-}
-  </script>
-</body>
-</html>

examples/textarea.js

@@ -1,14 +0,0 @@
-import { WebsocketProvider } from 'y-websocket'
-import { TextareaBinding } from 'y-textarea'
-
-import * as conf from './exampleConfig.js'
-
-const provider = new WebsocketProvider(conf.serverAddress)
-const ydocument = provider.get('textarea')
-const type = ydocument.getText('textarea')
-const textarea = document.querySelector('textarea')
-const binding = new TextareaBinding(type, textarea)
-
-window.textareaExample = {
-  provider, ydocument, type, textarea, binding
-}

package.json

@@ -1,80 +1,68 @@
 {
   "name": "yjs",
-  "version": "13.0.0-78",
-  "description": "A ",
+  "version": "13.0.0-102",
+  "description": "Shared Editing Library",
   "main": "./dist/yjs.js",
-  "module": "./dist/yjs.mjs'",
+  "module": "./dist/yjs.mjs",
   "sideEffects": false,
   "scripts": {
     "test": "npm run dist && PRODUCTION=1 node ./dist/tests.js --repitition-time 50 --production",
     "test-exhaustive": "npm run lint && npm run dist && node ./dist/tests.js --repitition-time 10000",
-    "dist": "rm -rf dist examples/build && rollup -c",
+    "dist": "rm -rf dist && rollup -c",
     "watch": "rollup -wc",
-    "lint": "standard && tsc",
-    "docs": "rm -rf docs; jsdoc --configure ./.jsdoc.json --verbose --readme ./README.v13.md --package ./package.json || true",
+    "lint": "markdownlint README.md && standard && tsc",
+    "docs": "rm -rf docs; jsdoc --configure ./.jsdoc.json --verbose --readme ./README.md --package ./package.json || true",
     "serve-docs": "npm run docs && serve ./docs/",
-    "postversion": "npm run lint && PRODUCTION=1 npm run dist && node ./dist/tests.js --repitition-time 1000",
+    "preversion": "npm run lint && PRODUCTION=1 npm run dist && npm run docs && node ./dist/tests.js --repitition-time 1000",
+    "postversion": "git push && git push --tags",
     "debug": "concurrently 'live-server --port=3443 --entry-file=test.html' 'npm run watch'",
     "trace-deopt": "clear && rollup -c  && node --trace-deopt dist/test.js",
     "trace-opt": "clear && rollup -c  && node --trace-opt dist/test.js"
   },
   "files": [
     "dist/*",
-    "examples/*",
-    "docs/*",
-    "README.md",
-    "LICENSE"
+    "src/*",
+    "tests/*",
+    "docs/*"
   ],
   "dictionaries": {
     "doc": "docs",
-    "example": "examples",
     "test": "tests"
   },
   "standard": {
     "ignore": [
       "/dist",
       "/node_modules",
-      "/docs",
-      "/examples/build"
+      "/docs"
     ]
   },
   "repository": {
     "type": "git",
-    "url": "https://github.com/y-js/yjs.git"
+    "url": "https://github.com/yjs/yjs.git"
   },
   "keywords": [
     "crdt"
   ],
   "author": "Kevin Jahns",
-  "email": "kevin.jahns@rwth-aachen.de",
+  "email": "kevin.jahns@protonmail.com",
   "license": "MIT",
   "bugs": {
-    "url": "https://github.com/y-js/yjs/issues"
+    "url": "https://github.com/yjs/yjs/issues"
   },
-  "homepage": "http://y-js.org",
+  "homepage": "https://yjs.dev",
   "dependencies": {
-    "lib0": "0.0.0"
+    "lib0": "^0.1.1"
   },
   "devDependencies": {
-    "codemirror": "^5.42.0",
     "concurrently": "^3.6.1",
-    "esdoc": "^1.1.0",
-    "esdoc-standard-plugin": "^1.0.0",
-    "jsdoc": "^3.5.5",
+    "jsdoc": "^3.6.3",
     "live-server": "^1.2.1",
-    "prosemirror-example-setup": "^1.0.1",
-    "prosemirror-schema-basic": "^1.0.0",
-    "prosemirror-state": "^1.2.2",
-    "prosemirror-view": "^1.6.5",
-    "quill": "^1.3.6",
-    "quill-cursors": "^1.0.3",
-    "rollup": "^1.1.2",
+    "rollup": "^1.20.3",
     "rollup-cli": "^1.0.9",
-    "rollup-plugin-commonjs": "^9.2.0",
-    "rollup-plugin-node-resolve": "^4.0.0",
-    "rollup-plugin-terser": "^4.0.4",
+    "rollup-plugin-node-resolve": "^4.2.4",
     "standard": "^11.0.1",
     "tui-jsdoc-template": "^1.2.2",
-    "typescript": "^3.3.3333"
+    "typescript": "^3.6.2",
+    "y-protocols": "0.0.6"
   }
 }

rollup.config.js

@@ -1,6 +1,6 @@
 import nodeResolve from 'rollup-plugin-node-resolve'
-import commonjs from 'rollup-plugin-commonjs'
-import { terser } from 'rollup-plugin-terser'
+
+const localImports = process.env.LOCALIMPORTS
 
 const customModules = new Set([
   'y-websocket',
@@ -23,31 +23,18 @@ const debugResolve = {
     if (importee === 'yjs') {
       return `${process.cwd()}/src/index.js`
     }
-    if (customModules.has(importee.split('/')[0])) {
-      return `${process.cwd()}/../${importee}/src/${importee}.js`
-    }
-    if (customLibModules.has(importee.split('/')[0])) {
-      return `${process.cwd()}/../${importee}`
+    if (localImports) {
+      if (customModules.has(importee.split('/')[0])) {
+        return `${process.cwd()}/../${importee}/src/${importee}.js`
+      }
+      if (customLibModules.has(importee.split('/')[0])) {
+        return `${process.cwd()}/../${importee}`
+      }
     }
     return null
   }
 }
 
-const minificationPlugins = process.env.PRODUCTION ? [terser({
-  module: true,
-  compress: {
-    hoist_vars: true,
-    module: true,
-    passes: 5,
-    pure_getters: true,
-    unsafe_comps: true,
-    unsafe_undefined: true
-  },
-  mangle: {
-    toplevel: true
-  }
-})] : []
-
 export default [{
   input: './src/index.js',
   output: [{
@@ -80,26 +67,7 @@ export default [{
     debugResolve,
     nodeResolve({
       sourcemap: true,
-      module: true,
-      browser: true
-    }),
-    commonjs()
-  ]
-}, {
-  input: ['./examples/codemirror.js', './examples/textarea.js'], // './examples/quill.js', './examples/dom.js', './examples/prosemirror.js'
-  output: {
-    dir: 'examples/build',
-    format: 'esm',
-    sourcemap: true
-  },
-  plugins: [
-    debugResolve,
-    nodeResolve({
-      sourcemap: true,
-      module: true,
-      browser: true
-    }),
-    commonjs(),
-    ...minificationPlugins
+      mainFields: ['module', 'browser', 'main']
+    })
   ]
 }]

src/index.js

@@ -1,6 +1,6 @@
 
 export {
-  Y,
+  Doc,
   Transaction,
   YArray as Array,
   YMap as Map,
@@ -9,18 +9,50 @@ export {
   YXmlHook as XmlHook,
   YXmlElement as XmlElement,
   YXmlFragment as XmlFragment,
-  createCursorFromTypeOffset,
-  createCursorFromJSON,
-  createAbsolutePositionFromCursor,
-  writeCursor,
-  readCursor,
+  YXmlEvent,
+  YMapEvent,
+  YArrayEvent,
+  YEvent,
+  Item,
+  AbstractStruct,
+  GC,
+  ContentBinary,
+  ContentDeleted,
+  ContentEmbed,
+  ContentFormat,
+  ContentJSON,
+  ContentAny,
+  ContentString,
+  ContentType,
+  AbstractType,
+  RelativePosition,
+  createRelativePositionFromTypeIndex,
+  createRelativePositionFromJSON,
+  createAbsolutePositionFromRelativePosition,
+  compareRelativePositions,
+  writeRelativePosition,
+  readRelativePosition,
   ID,
   createID,
   compareIDs,
   getState,
-  getStates,
-  readStatesAsMap,
-  writeStates,
-  writeModel,
-  readModel
+  Snapshot,
+  createSnapshot,
+  createDeleteSet,
+  createDeleteSetFromStructStore,
+  snapshot,
+  emptySnapshot,
+  findRootTypeKey,
+  typeListToArraySnapshot,
+  typeMapGetSnapshot,
+  iterateDeletedStructs,
+  applyUpdate,
+  encodeStateAsUpdate,
+  encodeStateVector,
+  UndoManager,
+  decodeSnapshot,
+  encodeSnapshot,
+  isDeleted,
+  equalSnapshots,
+  PermanentUserData // @TODO experimental
 } from './internals.js'

src/internals.js

@@ -1,33 +1,36 @@
+
 export * from './utils/DeleteSet.js'
+export * from './utils/Doc.js'
+export * from './utils/encoding.js'
 export * from './utils/EventHandler.js'
 export * from './utils/ID.js'
 export * from './utils/isParentOf.js'
-export * from './utils/cursor.js'
+export * from './utils/PermanentUserData.js'
+export * from './utils/RelativePosition.js'
 export * from './utils/Snapshot.js'
 export * from './utils/StructStore.js'
 export * from './utils/Transaction.js'
-// export * from './utils/UndoManager.js'
-export * from './utils/Y.js'
+export * from './utils/UndoManager.js'
 export * from './utils/YEvent.js'
 
 export * from './types/AbstractType.js'
 export * from './types/YArray.js'
 export * from './types/YMap.js'
 export * from './types/YText.js'
+export * from './types/YXmlFragment.js'
 export * from './types/YXmlElement.js'
 export * from './types/YXmlEvent.js'
 export * from './types/YXmlHook.js'
 export * from './types/YXmlText.js'
 
 export * from './structs/AbstractStruct.js'
-export * from './structs/AbstractItem.js'
 export * from './structs/GC.js'
-export * from './structs/ItemBinary.js'
-export * from './structs/ItemDeleted.js'
-export * from './structs/ItemEmbed.js'
-export * from './structs/ItemFormat.js'
-export * from './structs/ItemJSON.js'
-export * from './structs/ItemString.js'
-export * from './structs/ItemType.js'
-
-export * from './utils/encoding.js'
+export * from './structs/ContentBinary.js'
+export * from './structs/ContentDeleted.js'
+export * from './structs/ContentEmbed.js'
+export * from './structs/ContentFormat.js'
+export * from './structs/ContentJSON.js'
+export * from './structs/ContentAny.js'
+export * from './structs/ContentString.js'
+export * from './structs/ContentType.js'
+export * from './structs/Item.js'

src/structs/AbstractStruct.js

@@ -1,6 +1,6 @@
 
 import {
-  Y, StructStore, ID, Transaction // eslint-disable-line
+  StructStore, ID, Transaction // eslint-disable-line
 } from '../internals.js'
 
 import * as encoding from 'lib0/encoding.js' // eslint-disable-line
@@ -12,14 +12,16 @@ import * as error from 'lib0/error.js'
 export class AbstractStruct {
   /**
    * @param {ID} id
+   * @param {number} length
    */
-  constructor (id) {
+  constructor (id, length) {
     /**
      * The uniqe identifier of this struct.
      * @type {ID}
      * @readonly
      */
     this.id = id
+    this.length = length
     this.deleted = false
   }
   /**
@@ -32,12 +34,6 @@ export class AbstractStruct {
   mergeWith (right) {
     return false
   }
-  /**
-   * @type {number}
-   */
-  get length () {
-    throw error.methodUnimplemented()
-  }
   /**
    * @param {encoding.Encoder} encoder The encoder to write data to.
    * @param {number} offset
@@ -89,10 +85,4 @@ export class AbstractStructRef {
   toStruct (transaction, store, offset) {
     throw error.methodUnimplemented()
   }
-  /**
-   * @type {number}
-   */
-  get length () {
-    return 1
-  }
 }

src/structs/ContentAny.js

@@ -0,0 +1,108 @@
+import {
+  Transaction, Item, StructStore // eslint-disable-line
+} from '../internals.js'
+
+import * as encoding from 'lib0/encoding.js'
+import * as decoding from 'lib0/decoding.js'
+
+/**
+ * @private
+ */
+export class ContentAny {
+  /**
+   * @param {Array<any>} arr
+   */
+  constructor (arr) {
+    /**
+     * @type {Array<any>}
+     */
+    this.arr = arr
+  }
+  /**
+   * @return {number}
+   */
+  getLength () {
+    return this.arr.length
+  }
+  /**
+   * @return {Array<any>}
+   */
+  getContent () {
+    return this.arr
+  }
+  /**
+   * @return {boolean}
+   */
+  isCountable () {
+    return true
+  }
+  /**
+   * @return {ContentAny}
+   */
+  copy () {
+    return new ContentAny(this.arr)
+  }
+  /**
+   * @param {number} offset
+   * @return {ContentAny}
+   */
+  splice (offset) {
+    const right = new ContentAny(this.arr.slice(offset))
+    this.arr = this.arr.slice(0, offset)
+    return right
+  }
+  /**
+   * @param {ContentAny} right
+   * @return {boolean}
+   */
+  mergeWith (right) {
+    this.arr = this.arr.concat(right.arr)
+    return true
+  }
+  /**
+   * @param {Transaction} transaction
+   * @param {Item} item
+   */
+  integrate (transaction, item) {}
+  /**
+   * @param {Transaction} transaction
+   */
+  delete (transaction) {}
+  /**
+   * @param {StructStore} store
+   */
+  gc (store) {}
+  /**
+   * @param {encoding.Encoder} encoder
+   * @param {number} offset
+   */
+  write (encoder, offset) {
+    const len = this.arr.length
+    encoding.writeVarUint(encoder, len - offset)
+    for (let i = offset; i < len; i++) {
+      const c = this.arr[i]
+      encoding.writeAny(encoder, c)
+    }
+  }
+  /**
+   * @return {number}
+   */
+  getRef () {
+    return 8
+  }
+}
+
+/**
+ * @private
+ *
+ * @param {decoding.Decoder} decoder
+ * @return {ContentAny}
+ */
+export const readContentAny = decoder => {
+  const len = decoding.readVarUint(decoder)
+  const cs = []
+  for (let i = 0; i < len; i++) {
+    cs.push(decoding.readAny(decoder))
+  }
+  return new ContentAny(cs)
+}

src/structs/ContentBinary.js

@@ -0,0 +1,92 @@
+import {
+  StructStore, Item, Transaction // eslint-disable-line
+} from '../internals.js'
+
+import * as encoding from 'lib0/encoding.js'
+import * as decoding from 'lib0/decoding.js'
+import * as buffer from 'lib0/buffer.js'
+import * as error from 'lib0/error.js'
+
+/**
+ * @private
+ */
+export class ContentBinary {
+  /**
+   * @param {Uint8Array} content
+   */
+  constructor (content) {
+    this.content = content
+  }
+  /**
+   * @return {number}
+   */
+  getLength () {
+    return 1
+  }
+  /**
+   * @return {Array<any>}
+   */
+  getContent () {
+    return [this.content]
+  }
+  /**
+   * @return {boolean}
+   */
+  isCountable () {
+    return true
+  }
+  /**
+   * @return {ContentBinary}
+   */
+  copy () {
+    return new ContentBinary(this.content)
+  }
+  /**
+   * @param {number} offset
+   * @return {ContentBinary}
+   */
+  splice (offset) {
+    throw error.methodUnimplemented()
+  }
+  /**
+   * @param {ContentBinary} right
+   * @return {boolean}
+   */
+  mergeWith (right) {
+    return false
+  }
+  /**
+   * @param {Transaction} transaction
+   * @param {Item} item
+   */
+  integrate (transaction, item) {}
+  /**
+   * @param {Transaction} transaction
+   */
+  delete (transaction) {}
+  /**
+   * @param {StructStore} store
+   */
+  gc (store) {}
+  /**
+   * @param {encoding.Encoder} encoder
+   * @param {number} offset
+   */
+  write (encoder, offset) {
+    encoding.writeVarUint8Array(encoder, this.content)
+  }
+  /**
+   * @return {number}
+   */
+  getRef () {
+    return 3
+  }
+}
+
+/**
+ * @private
+ *
+ * @param {decoding.Decoder} decoder
+ * @return {ContentBinary}
+ */
+export const readContentBinary = decoder => new ContentBinary(buffer.copyUint8Array(decoding.readVarUint8Array(decoder)))

src/structs/ContentDeleted.js

@@ -0,0 +1,98 @@
+
+import {
+  addToDeleteSet,
+  StructStore, Item, Transaction // eslint-disable-line
+} from '../internals.js'
+
+import * as encoding from 'lib0/encoding.js'
+import * as decoding from 'lib0/decoding.js'
+
+/**
+ * @private
+ */
+export class ContentDeleted {
+  /**
+   * @param {number} len
+   */
+  constructor (len) {
+    this.len = len
+  }
+  /**
+   * @return {number}
+   */
+  getLength () {
+    return this.len
+  }
+  /**
+   * @return {Array<any>}
+   */
+  getContent () {
+    return []
+  }
+  /**
+   * @return {boolean}
+   */
+  isCountable () {
+    return false
+  }
+  /**
+   * @return {ContentDeleted}
+   */
+  copy () {
+    return new ContentDeleted(this.len)
+  }
+  /**
+   * @param {number} offset
+   * @return {ContentDeleted}
+   */
+  splice (offset) {
+    const right = new ContentDeleted(this.len - offset)
+    this.len = offset
+    return right
+  }
+  /**
+   * @param {ContentDeleted} right
+   * @return {boolean}
+   */
+  mergeWith (right) {
+    this.len += right.len
+    return true
+  }
+  /**
+   * @param {Transaction} transaction
+   * @param {Item} item
+   */
+  integrate (transaction, item) {
+    addToDeleteSet(transaction.deleteSet, item.id, this.len)
+    item.deleted = true
+  }
+  /**
+   * @param {Transaction} transaction
+   */
+  delete (transaction) {}
+  /**
+   * @param {StructStore} store
+   */
+  gc (store) {}
+  /**
+   * @param {encoding.Encoder} encoder
+   * @param {number} offset
+   */
+  write (encoder, offset) {
+    encoding.writeVarUint(encoder, this.len - offset)
+  }
+  /**
+   * @return {number}
+   */
+  getRef () {
+    return 1
+  }
+}
+
+/**
+ * @private
+ *
+ * @param {decoding.Decoder} decoder
+ * @return {ContentDeleted}
+ */
+export const readContentDeleted = decoder => new ContentDeleted(decoding.readVarUint(decoder))

src/structs/ContentEmbed.js

@@ -0,0 +1,92 @@
+
+import {
+  StructStore, Item, Transaction // eslint-disable-line
+} from '../internals.js'
+
+import * as encoding from 'lib0/encoding.js'
+import * as decoding from 'lib0/decoding.js'
+import * as error from 'lib0/error.js'
+
+/**
+ * @private
+ */
+export class ContentEmbed {
+  /**
+   * @param {Object} embed
+   */
+  constructor (embed) {
+    this.embed = embed
+  }
+  /**
+   * @return {number}
+   */
+  getLength () {
+    return 1
+  }
+  /**
+   * @return {Array<any>}
+   */
+  getContent () {
+    return [this.embed]
+  }
+  /**
+   * @return {boolean}
+   */
+  isCountable () {
+    return true
+  }
+  /**
+   * @return {ContentEmbed}
+   */
+  copy () {
+    return new ContentEmbed(this.embed)
+  }
+  /**
+   * @param {number} offset
+   * @return {ContentEmbed}
+   */
+  splice (offset) {
+    throw error.methodUnimplemented()
+  }
+  /**
+   * @param {ContentEmbed} right
+   * @return {boolean}
+   */
+  mergeWith (right) {
+    return false
+  }
+  /**
+   * @param {Transaction} transaction
+   * @param {Item} item
+   */
+  integrate (transaction, item) {}
+  /**
+   * @param {Transaction} transaction
+   */
+  delete (transaction) {}
+  /**
+   * @param {StructStore} store
+   */
+  gc (store) {}
+  /**
+   * @param {encoding.Encoder} encoder
+   * @param {number} offset
+   */
+  write (encoder, offset) {
+    encoding.writeVarString(encoder, JSON.stringify(this.embed))
+  }
+  /**
+   * @return {number}
+   */
+  getRef () {
+    return 5
+  }
+}
+
+/**
+ * @private
+ *
+ * @param {decoding.Decoder} decoder
+ * @return {ContentEmbed}
+ */
+export const readContentEmbed = decoder => new ContentEmbed(JSON.parse(decoding.readVarString(decoder)))

src/structs/ContentFormat.js

@@ -0,0 +1,95 @@
+
+import {
+  Item, StructStore, Transaction // eslint-disable-line
+} from '../internals.js'
+
+import * as encoding from 'lib0/encoding.js'
+import * as decoding from 'lib0/decoding.js'
+import * as error from 'lib0/error.js'
+
+/**
+ * @private
+ */
+export class ContentFormat {
+  /**
+   * @param {string} key
+   * @param {Object} value
+   */
+  constructor (key, value) {
+    this.key = key
+    this.value = value
+  }
+  /**
+   * @return {number}
+   */
+  getLength () {
+    return 1
+  }
+  /**
+   * @return {Array<any>}
+   */
+  getContent () {
+    return []
+  }
+  /**
+   * @return {boolean}
+   */
+  isCountable () {
+    return false
+  }
+  /**
+   * @return {ContentFormat}
+   */
+  copy () {
+    return new ContentFormat(this.key, this.value)
+  }
+  /**
+   * @param {number} offset
+   * @return {ContentFormat}
+   */
+  splice (offset) {
+    throw error.methodUnimplemented()
+  }
+  /**
+   * @param {ContentFormat} right
+   * @return {boolean}
+   */
+  mergeWith (right) {
+    return false
+  }
+  /**
+   * @param {Transaction} transaction
+   * @param {Item} item
+   */
+  integrate (transaction, item) {}
+  /**
+   * @param {Transaction} transaction
+   */
+  delete (transaction) {}
+  /**
+   * @param {StructStore} store
+   */
+  gc (store) {}
+  /**
+   * @param {encoding.Encoder} encoder
+   * @param {number} offset
+   */
+  write (encoder, offset) {
+    encoding.writeVarString(encoder, this.key)
+    encoding.writeVarString(encoder, JSON.stringify(this.value))
+  }
+  /**
+   * @return {number}
+   */
+  getRef () {
+    return 6
+  }
+}
+
+/**
+ * @private
+ *
+ * @param {decoding.Decoder} decoder
+ * @return {ContentFormat}
+ */
+export const readContentFormat = decoder => new ContentFormat(decoding.readVarString(decoder), JSON.parse(decoding.readVarString(decoder)))

src/structs/ContentJSON.js

@@ -0,0 +1,113 @@
+import {
+  Transaction, Item, StructStore // eslint-disable-line
+} from '../internals.js'
+
+import * as encoding from 'lib0/encoding.js'
+import * as decoding from 'lib0/decoding.js'
+
+/**
+ * @private
+ */
+export class ContentJSON {
+  /**
+   * @param {Array<any>} arr
+   */
+  constructor (arr) {
+    /**
+     * @type {Array<any>}
+     */
+    this.arr = arr
+  }
+  /**
+   * @return {number}
+   */
+  getLength () {
+    return this.arr.length
+  }
+  /**
+   * @return {Array<any>}
+   */
+  getContent () {
+    return this.arr
+  }
+  /**
+   * @return {boolean}
+   */
+  isCountable () {
+    return true
+  }
+  /**
+   * @return {ContentJSON}
+   */
+  copy () {
+    return new ContentJSON(this.arr)
+  }
+  /**
+   * @param {number} offset
+   * @return {ContentJSON}
+   */
+  splice (offset) {
+    const right = new ContentJSON(this.arr.slice(offset))
+    this.arr = this.arr.slice(0, offset)
+    return right
+  }
+  /**
+   * @param {ContentJSON} right
+   * @return {boolean}
+   */
+  mergeWith (right) {
+    this.arr = this.arr.concat(right.arr)
+    return true
+  }
+  /**
+   * @param {Transaction} transaction
+   * @param {Item} item
+   */
+  integrate (transaction, item) {}
+  /**
+   * @param {Transaction} transaction
+   */
+  delete (transaction) {}
+  /**
+   * @param {StructStore} store
+   */
+  gc (store) {}
+  /**
+   * @param {encoding.Encoder} encoder
+   * @param {number} offset
+   */
+  write (encoder, offset) {
+    const len = this.arr.length
+    encoding.writeVarUint(encoder, len - offset)
+    for (let i = offset; i < len; i++) {
+      const c = this.arr[i]
+      encoding.writeVarString(encoder, c === undefined ? 'undefined' : JSON.stringify(c))
+    }
+  }
+  /**
+   * @return {number}
+   */
+  getRef () {
+    return 2
+  }
+}
+
+/**
+ * @private
+ *
+ * @param {decoding.Decoder} decoder
+ * @return {ContentJSON}
+ */
+export const readContentJSON = decoder => {
+  const len = decoding.readVarUint(decoder)
+  const cs = []
+  for (let i = 0; i < len; i++) {
+    const c = decoding.readVarString(decoder)
+    if (c === 'undefined') {
+      cs.push(undefined)
+    } else {
+      cs.push(JSON.parse(c))
+    }
+  }
+  return new ContentJSON(cs)
+}

src/structs/ContentString.js

@@ -0,0 +1,96 @@
+import {
+  Transaction, Item, StructStore // eslint-disable-line
+} from '../internals.js'
+
+import * as encoding from 'lib0/encoding.js'
+import * as decoding from 'lib0/decoding.js'
+
+/**
+ * @private
+ */
+export class ContentString {
+  /**
+   * @param {string} str
+   */
+  constructor (str) {
+    /**
+     * @type {string}
+     */
+    this.str = str
+  }
+  /**
+   * @return {number}
+   */
+  getLength () {
+    return this.str.length
+  }
+  /**
+   * @return {Array<any>}
+   */
+  getContent () {
+    return this.str.split('')
+  }
+  /**
+   * @return {boolean}
+   */
+  isCountable () {
+    return true
+  }
+  /**
+   * @return {ContentString}
+   */
+  copy () {
+    return new ContentString(this.str)
+  }
+  /**
+   * @param {number} offset
+   * @return {ContentString}
+   */
+  splice (offset) {
+    const right = new ContentString(this.str.slice(offset))
+    this.str = this.str.slice(0, offset)
+    return right
+  }
+  /**
+   * @param {ContentString} right
+   * @return {boolean}
+   */
+  mergeWith (right) {
+    this.str += right.str
+    return true
+  }
+  /**
+   * @param {Transaction} transaction
+   * @param {Item} item
+   */
+  integrate (transaction, item) {}
+  /**
+   * @param {Transaction} transaction
+   */
+  delete (transaction) {}
+  /**
+   * @param {StructStore} store
+   */
+  gc (store) {}
+  /**
+   * @param {encoding.Encoder} encoder
+   * @param {number} offset
+   */
+  write (encoder, offset) {
+    encoding.writeVarString(encoder, offset === 0 ? this.str : this.str.slice(offset))
+  }
+  /**
+   * @return {number}
+   */
+  getRef () {
+    return 4
+  }
+}
+
+/**
+ * @private
+ *
+ * @param {decoding.Decoder} decoder
+ * @return {ContentString}
+ */
+export const readContentString = decoder => new ContentString(decoding.readVarString(decoder))

src/structs/ContentType.js

@@ -0,0 +1,163 @@
+
+import {
+  readYArray,
+  readYMap,
+  readYText,
+  readYXmlElement,
+  readYXmlFragment,
+  readYXmlHook,
+  readYXmlText,
+  StructStore, Transaction, Item, YEvent, AbstractType // eslint-disable-line
+} from '../internals.js'
+
+import * as encoding from 'lib0/encoding.js' // eslint-disable-line
+import * as decoding from 'lib0/decoding.js'
+import * as error from 'lib0/error.js'
+
+/**
+ * @type {Array<function(decoding.Decoder):AbstractType<any>>}
+ * @private
+ */
+export const typeRefs = [
+  readYArray,
+  readYMap,
+  readYText,
+  readYXmlElement,
+  readYXmlFragment,
+  readYXmlHook,
+  readYXmlText
+]
+
+export const YArrayRefID = 0
+export const YMapRefID = 1
+export const YTextRefID = 2
+export const YXmlElementRefID = 3
+export const YXmlFragmentRefID = 4
+export const YXmlHookRefID = 5
+export const YXmlTextRefID = 6
+
+/**
+ * @private
+ */
+export class ContentType {
+  /**
+   * @param {AbstractType<YEvent>} type
+   */
+  constructor (type) {
+    /**
+     * @type {AbstractType<any>}
+     */
+    this.type = type
+  }
+  /**
+   * @return {number}
+   */
+  getLength () {
+    return 1
+  }
+  /**
+   * @return {Array<any>}
+   */
+  getContent () {
+    return [this.type]
+  }
+  /**
+   * @return {boolean}
+   */
+  isCountable () {
+    return true
+  }
+  /**
+   * @return {ContentType}
+   */
+  copy () {
+    return new ContentType(this.type._copy())
+  }
+  /**
+   * @param {number} offset
+   * @return {ContentType}
+   */
+  splice (offset) {
+    throw error.methodUnimplemented()
+  }
+  /**
+   * @param {ContentType} right
+   * @return {boolean}
+   */
+  mergeWith (right) {
+    return false
+  }
+  /**
+   * @param {Transaction} transaction
+   * @param {Item} item
+   */
+  integrate (transaction, item) {
+    this.type._integrate(transaction.doc, item)
+  }
+  /**
+   * @param {Transaction} transaction
+   */
+  delete (transaction) {
+    let item = this.type._start
+    while (item !== null) {
+      if (!item.deleted) {
+        item.delete(transaction)
+      } else {
+        // Whis will be gc'd later and we want to merge it if possible
+        // We try to merge all deleted items after each transaction,
+        // but we have no knowledge about that this needs to be merged
+        // since it is not in transaction.ds. Hence we add it to transaction._mergeStructs
+        transaction._mergeStructs.add(item.id)
+      }
+      item = item.right
+    }
+    this.type._map.forEach(item => {
+      if (!item.deleted) {
+        item.delete(transaction)
+      } else {
+        // same as above
+        transaction._mergeStructs.add(item.id)
+      }
+    })
+    transaction.changed.delete(this.type)
+  }
+  /**
+   * @param {StructStore} store
+   */
+  gc (store) {
+    let item = this.type._start
+    while (item !== null) {
+      item.gc(store, true)
+      item = item.right
+    }
+    this.type._start = null
+    this.type._map.forEach(/** @param {Item | null} item */ (item) => {
+      while (item !== null) {
+        item.gc(store, true)
+        item = item.left
+      }
+    })
+    this.type._map = new Map()
+  }
+  /**
+   * @param {encoding.Encoder} encoder
+   * @param {number} offset
+   */
+  write (encoder, offset) {
+    this.type._write(encoder)
+  }
+  /**
+   * @return {number}
+   */
+  getRef () {
+    return 7
+  }
+}
+
+/**
+ * @private
+ *
+ * @param {decoding.Decoder} decoder
+ * @return {ContentType}
+ */
+export const readContentType = decoder => new ContentType(typeRefs[decoding.readVarUint(decoder)](decoder))

src/structs/GC.js

@@ -4,7 +4,7 @@ import {
   AbstractStruct,
   createID,
   addStruct,
-  Y, StructStore, Transaction, ID // eslint-disable-line
+  StructStore, Transaction, ID // eslint-disable-line
 } from '../internals.js'
 
 import * as decoding from 'lib0/decoding.js'
@@ -21,26 +21,18 @@ export class GC extends AbstractStruct {
    * @param {number} length
    */
   constructor (id, length) {
-    super(id)
-    /**
-     * @type {number}
-     */
-    this._len = length
+    super(id, length)
     this.deleted = true
   }
 
-  get length () {
-    return this._len
-  }
-
   delete () {}
 
   /**
-   * @param {AbstractStruct} right
+   * @param {GC} right
    * @return {boolean}
    */
   mergeWith (right) {
-    this._len += right.length
+    this.length += right.length
     return true
   }
 
@@ -48,7 +40,7 @@ export class GC extends AbstractStruct {
    * @param {Transaction} transaction
    */
   integrate (transaction) {
-    addStruct(transaction.y.store, this)
+    addStruct(transaction.doc.store, this)
   }
 
   /**
@@ -57,7 +49,7 @@ export class GC extends AbstractStruct {
    */
   write (encoder, offset) {
     encoding.writeUint8(encoder, structGCRefNumber)
-    encoding.writeVarUint(encoder, this._len - offset)
+    encoding.writeVarUint(encoder, this.length - offset)
   }
 }
 
@@ -75,15 +67,7 @@ export class GCRef extends AbstractStructRef {
     /**
      * @type {number}
      */
-    this._len = decoding.readVarUint(decoder)
-  }
-  get length () {
-    return this._len
-  }
-  missing () {
-    return [
-      createID(this.id.client, this.id.clock - 1)
-    ]
+    this.length = decoding.readVarUint(decoder)
   }
   /**
    * @param {Transaction} transaction
@@ -95,11 +79,11 @@ export class GCRef extends AbstractStructRef {
     if (offset > 0) {
       // @ts-ignore
       this.id = createID(this.id.client, this.id.clock + offset)
-      this._len = this._len - offset
+      this.length -= offset
     }
     return new GC(
       this.id,
-      this._len
+      this.length
     )
   }
 }

src/structs/Item.js

@@ -10,14 +10,21 @@ import {
   replaceStruct,
   addStruct,
   addToDeleteSet,
-  ItemDeleted,
   findRootTypeKey,
   compareIDs,
   getItem,
-  getItemType,
   getItemCleanEnd,
   getItemCleanStart,
-  YEvent, StructStore, ID, AbstractType, Y, Transaction // eslint-disable-line
+  readContentDeleted,
+  readContentBinary,
+  readContentJSON,
+  readContentAny,
+  readContentString,
+  readContentEmbed,
+  readContentFormat,
+  readContentType,
+  addChangedTypeToTransaction,
+  ContentType, ContentDeleted, StructStore, ID, AbstractType, Transaction // eslint-disable-line
 } from '../internals.js'
 
 import * as error from 'lib0/error.js'
@@ -27,12 +34,54 @@ import * as maplib from 'lib0/map.js'
 import * as set from 'lib0/set.js'
 import * as binary from 'lib0/binary.js'
 
+/**
+ * @todo This should return several items
+ *
+ * @param {StructStore} store
+ * @param {ID} id
+ * @return {{item:Item, diff:number}}
+ */
+export const followRedone = (store, id) => {
+  /**
+   * @type {ID|null}
+   */
+  let nextID = id
+  let diff = 0
+  let item
+  do {
+    if (diff > 0) {
+      nextID = createID(nextID.client, nextID.clock + diff)
+    }
+    item = getItem(store, nextID)
+    diff = nextID.clock - item.id.clock
+    nextID = item.redone
+  } while (nextID !== null)
+  return {
+    item, diff
+  }
+}
+
+/**
+ * Make sure that neither item nor any of its parents is ever deleted.
+ *
+ * This property does not persist when storing it into a database or when
+ * sending it to other peers
+ *
+ * @param {Item|null} item
+ */
+export const keepItem = item => {
+  while (item !== null && !item.keep) {
+    item.keep = true
+    item = item.parent._item
+  }
+}
+
 /**
  * Split leftItem into two items
  * @param {Transaction} transaction
- * @param {AbstractItem} leftItem
+ * @param {Item} leftItem
  * @param {number} diff
- * @return {AbstractItem}
+ * @return {Item}
  *
  * @function
  * @private
@@ -40,18 +89,25 @@ import * as binary from 'lib0/binary.js'
 export const splitItem = (transaction, leftItem, diff) => {
   const id = leftItem.id
   // create rightItem
-  const rightItem = leftItem.copy(
+  const rightItem = new Item(
     createID(id.client, id.clock + diff),
     leftItem,
     createID(id.client, id.clock + diff - 1),
     leftItem.right,
     leftItem.rightOrigin,
     leftItem.parent,
-    leftItem.parentSub
+    leftItem.parentSub,
+    leftItem.content.splice(diff)
   )
   if (leftItem.deleted) {
     rightItem.deleted = true
   }
+  if (leftItem.keep) {
+    rightItem.keep = true
+  }
+  if (leftItem.redone !== null) {
+    rightItem.redone = createID(leftItem.redone.client, leftItem.redone.clock + diff)
+  }
   // update left (do not set leftItem.rightOrigin as it will lead to problems when syncing)
   leftItem.right = rightItem
   // update right
@@ -60,24 +116,131 @@ export const splitItem = (transaction, leftItem, diff) => {
   }
   // right is more specific.
   transaction._mergeStructs.add(rightItem.id)
+  // update parent._map
+  if (rightItem.parentSub !== null && rightItem.right === null) {
+    rightItem.parent._map.set(rightItem.parentSub, rightItem)
+  }
+  leftItem.length = diff
   return rightItem
 }
 
+/**
+ * Redoes the effect of this operation.
+ *
+ * @param {Transaction} transaction The Yjs instance.
+ * @param {Item} item
+ * @param {Set<Item>} redoitems
+ *
+ * @return {Item|null}
+ *
+ * @private
+ */
+export const redoItem = (transaction, item, redoitems) => {
+  if (item.redone !== null) {
+    return getItemCleanStart(transaction, item.redone)
+  }
+  let parentItem = item.parent._item
+  /**
+   * @type {Item|null}
+   */
+  let left
+  /**
+   * @type {Item|null}
+   */
+  let right
+  if (item.parentSub === null) {
+    // Is an array item. Insert at the old position
+    left = item.left
+    right = item
+  } else {
+    // Is a map item. Insert as current value
+    left = item
+    while (left.right !== null) {
+      left = left.right
+      if (left.id.client !== transaction.doc.clientID) {
+        // It is not possible to redo this item because it conflicts with a
+        // change from another client
+        return null
+      }
+    }
+    if (left.right !== null) {
+      left = /** @type {Item} */ (item.parent._map.get(item.parentSub))
+    }
+    right = null
+  }
+  // make sure that parent is redone
+  if (parentItem !== null && parentItem.deleted === true && parentItem.redone === null) {
+    // try to undo parent if it will be undone anyway
+    if (!redoitems.has(parentItem) || redoItem(transaction, parentItem, redoitems) === null) {
+      return null
+    }
+  }
+  if (parentItem !== null && parentItem.redone !== null) {
+    while (parentItem.redone !== null) {
+      parentItem = getItemCleanStart(transaction, parentItem.redone)
+    }
+    // find next cloned_redo items
+    while (left !== null) {
+      /**
+       * @type {Item|null}
+       */
+      let leftTrace = left
+      // trace redone until parent matches
+      while (leftTrace !== null && leftTrace.parent._item !== parentItem) {
+        leftTrace = leftTrace.redone === null ? null : getItemCleanStart(transaction, leftTrace.redone)
+      }
+      if (leftTrace !== null && leftTrace.parent._item === parentItem) {
+        left = leftTrace
+        break
+      }
+      left = left.left
+    }
+    while (right !== null) {
+      /**
+       * @type {Item|null}
+       */
+      let rightTrace = right
+      // trace redone until parent matches
+      while (rightTrace !== null && rightTrace.parent._item !== parentItem) {
+        rightTrace = rightTrace.redone === null ? null : getItemCleanStart(transaction, rightTrace.redone)
+      }
+      if (rightTrace !== null && rightTrace.parent._item === parentItem) {
+        right = rightTrace
+        break
+      }
+      right = right.right
+    }
+  }
+  const redoneItem = new Item(
+    nextID(transaction),
+    left, left === null ? null : left.lastId,
+    right, right === null ? null : right.id,
+    parentItem === null ? item.parent : /** @type {ContentType} */ (parentItem.content).type,
+    item.parentSub,
+    item.content.copy()
+  )
+  item.redone = redoneItem.id
+  keepItem(redoneItem)
+  redoneItem.integrate(transaction)
+  return redoneItem
+}
+
 /**
  * Abstract class that represents any content.
  */
-export class AbstractItem extends AbstractStruct {
+export class Item extends AbstractStruct {
   /**
    * @param {ID} id
-   * @param {AbstractItem | null} left
+   * @param {Item | null} left
    * @param {ID | null} origin
-   * @param {AbstractItem | null} right
+   * @param {Item | null} right
    * @param {ID | null} rightOrigin
    * @param {AbstractType<any>} parent
    * @param {string | null} parentSub
+   * @param {AbstractContent} content
    */
-  constructor (id, left, origin, right, rightOrigin, parent, parentSub) {
-    super(id)
+  constructor (id, left, origin, right, rightOrigin, parent, parentSub, content) {
+    super(id, content.getLength())
     /**
      * The item that was originally to the left of this item.
      * @type {ID | null}
@@ -86,12 +249,12 @@ export class AbstractItem extends AbstractStruct {
     this.origin = origin
     /**
      * The item that is currently to the left of this item.
-     * @type {AbstractItem | null}
+     * @type {Item | null}
      */
     this.left = left
     /**
      * The item that is currently to the right of this item.
-     * @type {AbstractItem | null}
+     * @type {Item | null}
      */
     this.right = right
     /**
@@ -123,9 +286,19 @@ export class AbstractItem extends AbstractStruct {
     /**
      * If this type's effect is reundone this type refers to the type that undid
      * this operation.
-     * @type {AbstractItem | null}
+     * @type {ID | null}
      */
     this.redone = null
+    /**
+     * @type {AbstractContent}
+     */
+    this.content = content
+    this.length = content.getLength()
+    this.countable = content.isCountable()
+    /**
+     * If true, do not garbage collect this Item.
+     */
+    this.keep = false
   }
 
   /**
@@ -133,13 +306,13 @@ export class AbstractItem extends AbstractStruct {
    * @private
    */
   integrate (transaction) {
-    const store = transaction.y.store
+    const store = transaction.doc.store
     const id = this.id
     const parent = this.parent
     const parentSub = this.parentSub
     const length = this.length
     /**
-     * @type {AbstractItem|null}
+     * @type {Item|null}
      */
     let o
     // set o to the first conflicting item
@@ -155,11 +328,11 @@ export class AbstractItem extends AbstractStruct {
     }
     // TODO: use something like DeleteSet here (a tree implementation would be best)
     /**
-     * @type {Set<AbstractItem>}
+     * @type {Set<Item>}
      */
     const conflictingItems = new Set()
     /**
-     * @type {Set<AbstractItem>}
+     * @type {Set<Item>}
      */
     const itemsBeforeOrigin = new Set()
     // Let c in conflictingItems, b in itemsBeforeOrigin
@@ -218,8 +391,9 @@ export class AbstractItem extends AbstractStruct {
       parent._length += length
     }
     addStruct(store, this)
-    maplib.setIfUndefined(transaction.changed, parent, set.create).add(parentSub)
-    // @ts-ignore
+    this.content.integrate(transaction, this)
+    // add parent to transaction.changed
+    addChangedTypeToTransaction(transaction, parent, parentSub)
     if ((parent._item !== null && parent._item.deleted) || (this.right !== null && parentSub !== null)) {
       // delete if parent is deleted or if this is not the current attribute value of parent
       this.delete(transaction)
@@ -250,148 +424,44 @@ export class AbstractItem extends AbstractStruct {
     return n
   }
 
-  /**
-   * Creates an Item with the same effect as this Item (without position effect)
-   *
-   * @param {ID} id
-   * @param {AbstractItem | null} left
-   * @param {ID | null} origin
-   * @param {AbstractItem | null} right
-   * @param {ID | null} rightOrigin
-   * @param {AbstractType<any>} parent
-   * @param {string | null} parentSub
-   * @return {AbstractItem}
-   *
-   * @private
-   */
-  copy (id, left, origin, right, rightOrigin, parent, parentSub) {
-    throw new Error('unimplemented')
-  }
-
-  /**
-   * Redoes the effect of this operation.
-   *
-   * @param {Transaction} transaction The Yjs instance.
-   * @param {Set<AbstractItem>} redoitems
-   *
-   * @private
-   */
-  redo (transaction, redoitems) {
-    if (this.redone !== null) {
-      return this.redone
-    }
-    /**
-     * @type {any}
-     */
-    let parent = this.parent
-    if (parent === null) {
-      return
-    }
-    let left, right
-    if (this.parentSub === null) {
-      // Is an array item. Insert at the old position
-      left = this.left
-      right = this
-    } else {
-      // Is a map item. Insert as current value
-      left = parent.type._map.get(this.parentSub)
-      right = null
-    }
-    // make sure that parent is redone
-    if (parent._deleted === true && parent.redone === null) {
-      // try to undo parent if it will be undone anyway
-      if (!redoitems.has(parent) || !parent.redo(transaction, redoitems)) {
-        return false
-      }
-    }
-    if (parent.redone !== null) {
-      while (parent.redone !== null) {
-        parent = parent.redone
-      }
-      // find next cloned_redo items
-      while (left !== null) {
-        if (left.redone !== null && left.redone.parent === parent) {
-          left = left.redone
-          break
-        }
-        left = left.left
-      }
-      while (right !== null) {
-        if (right.redone !== null && right.redone.parent === parent) {
-          right = right.redone
-        }
-        right = right.right
-      }
-    }
-    this.redone = this.copy(nextID(transaction), left, left === null ? null : left.lastId, right, right === null ? null : right.id, parent, this.parentSub)
-    this.redone.integrate(transaction)
-    return true
-  }
-
   /**
    * Computes the last content address of this Item.
    */
   get lastId () {
     return createID(this.id.client, this.id.clock + this.length - 1)
   }
-
   /**
-   * Computes the length of this Item.
-   */
-  get length () {
-    return 1
-  }
-
-  /**
-   * Should return false if this Item is some kind of meta information
-   * (e.g. format information).
+   * Try to merge two items
    *
-   * * Whether this Item should be addressable via `yarray.get(i)`
-   * * Whether this Item should be counted when computing yarray.length
-   */
-  get countable () {
-    return true
-  }
-
-  /**
-   * Do not call directly. Always split via StructStore!
-   *
-   * Splits this Item so that another Item can be inserted in-between.
-   * This must be overwritten if _length > 1
-   * Returns right part after split
-   *
-   * (see {@link ItemJSON}/{@link ItemString} for implementation)
-   *
-   * Does not integrate the struct, nor store it in struct store.
-   *
-   * This method should only be cally by StructStore.
-   *
-   * @param {Transaction} transaction
-   * @param {number} diff
-   * @return {AbstractItem}
-   *
-   * @private
-   */
-  splitAt (transaction, diff) {
-    throw new Error('unimplemented')
-  }
-
-  /**
-   * @param {AbstractItem} right
+   * @param {Item} right
    * @return {boolean}
-   *
-   * @private
    */
   mergeWith (right) {
-    if (compareIDs(right.origin, this.lastId) && this.right === right && compareIDs(this.rightOrigin, right.rightOrigin)) {
+    if (
+      compareIDs(right.origin, this.lastId) &&
+      this.right === right &&
+      compareIDs(this.rightOrigin, right.rightOrigin) &&
+      this.id.client === right.id.client &&
+      this.id.clock + this.length === right.id.clock &&
+      this.deleted === right.deleted &&
+      this.redone === null &&
+      right.redone === null &&
+      this.content.constructor === right.content.constructor &&
+      this.content.mergeWith(right.content)
+    ) {
+      if (right.keep) {
+        this.keep = true
+      }
       this.right = right.right
       if (this.right !== null) {
         this.right.left = this
       }
+      this.length += right.length
       return true
     }
     return false
   }
+
   /**
    * Mark this Item as deleted.
    *
@@ -407,49 +477,26 @@ export class AbstractItem extends AbstractStruct {
       this.deleted = true
       addToDeleteSet(transaction.deleteSet, this.id, this.length)
       maplib.setIfUndefined(transaction.changed, parent, set.create).add(this.parentSub)
+      this.content.delete(transaction)
     }
   }
 
   /**
-   * @param {Transaction} transaction
    * @param {StructStore} store
+   * @param {boolean} parentGCd
    *
    * @private
    */
-  gcChildren (transaction, store) { }
-
-  /**
-   * @param {Transaction} transaction
-   * @param {StructStore} store
-   *
-   * @private
-   */
-  gc (transaction, store) {
-    let r
-    if (this.parent._item !== null && this.parent._item.deleted) {
-      r = new GC(this.id, this.length)
+  gc (store, parentGCd) {
+    if (!this.deleted) {
+      throw error.unexpectedCase()
+    }
+    this.content.gc(store)
+    if (parentGCd) {
+      replaceStruct(store, this, new GC(this.id, this.length))
     } else {
-      r = new ItemDeleted(this.id, this.left, this.origin, this.right, this.rightOrigin, this.parent, this.parentSub, this.length)
-      if (r.right !== null) {
-        r.right.left = r
-      } else if (r.parentSub !== null) {
-        r.parent._map.set(r.parentSub, r)
-      }
-      if (r.left !== null) {
-        r.left.right = r
-      } else if (r.parentSub === null) {
-        r.parent._start = r
-      }
+      this.content = new ContentDeleted(this.length)
     }
-    replaceStruct(store, this, r)
-    transaction._mergeStructs.add(r.id)
-  }
-
-  /**
-   * @return {Array<any>}
-   */
-  getContent () {
-    throw error.methodUnimplemented()
   }
 
   /**
@@ -460,15 +507,14 @@ export class AbstractItem extends AbstractStruct {
    *
    * @param {encoding.Encoder} encoder The encoder to write data to.
    * @param {number} offset
-   * @param {number} encodingRef
    *
    * @private
    */
-  write (encoder, offset, encodingRef) {
+  write (encoder, offset) {
     const origin = offset > 0 ? createID(this.id.client, this.id.clock + offset - 1) : this.origin
     const rightOrigin = this.rightOrigin
     const parentSub = this.parentSub
-    const info = (encodingRef & binary.BITS5) |
+    const info = (this.content.getRef() & binary.BITS5) |
       (origin === null ? 0 : binary.BIT8) | // origin is defined
       (rightOrigin === null ? 0 : binary.BIT7) | // right origin is defined
       (parentSub === null ? 0 : binary.BIT6) // parentSub is non-null
@@ -484,26 +530,130 @@ export class AbstractItem extends AbstractStruct {
       if (parent._item === null) {
         // parent type on y._map
         // find the correct key
-        // @ts-ignore we know that y exists
         const ykey = findRootTypeKey(parent)
         encoding.writeVarUint(encoder, 1) // write parentYKey
         encoding.writeVarString(encoder, ykey)
       } else {
         encoding.writeVarUint(encoder, 0) // write parent id
-        // @ts-ignore _item is defined because parent is integrated
         writeID(encoder, parent._item.id)
       }
       if (parentSub !== null) {
         encoding.writeVarString(encoder, parentSub)
       }
     }
+    this.content.write(encoder, offset)
+  }
+}
+
+/**
+ * @param {decoding.Decoder} decoder
+ * @param {number} info
+ */
+const readItemContent = (decoder, info) => contentRefs[info & binary.BITS5](decoder)
+
+/**
+ * A lookup map for reading Item content.
+ *
+ * @type {Array<function(decoding.Decoder):AbstractContent>}
+ */
+export const contentRefs = [
+  () => { throw error.unexpectedCase() }, // GC is not ItemContent
+  readContentDeleted,
+  readContentJSON,
+  readContentBinary,
+  readContentString,
+  readContentEmbed,
+  readContentFormat,
+  readContentType,
+  readContentAny
+]
+
+/**
+ * Do not implement this class!
+ */
+export class AbstractContent {
+  /**
+   * @return {number}
+   */
+  getLength () {
+    throw error.methodUnimplemented()
+  }
+  /**
+   * @return {Array<any>}
+   */
+  getContent () {
+    throw error.methodUnimplemented()
+  }
+  /**
+   * Should return false if this Item is some kind of meta information
+   * (e.g. format information).
+   *
+   * * Whether this Item should be addressable via `yarray.get(i)`
+   * * Whether this Item should be counted when computing yarray.length
+   *
+   * @return {boolean}
+   */
+  isCountable () {
+    throw error.methodUnimplemented()
+  }
+  /**
+   * @return {AbstractContent}
+   */
+  copy () {
+    throw error.methodUnimplemented()
+  }
+  /**
+   * @param {number} offset
+   * @return {AbstractContent}
+   */
+  splice (offset) {
+    throw error.methodUnimplemented()
+  }
+  /**
+   * @param {AbstractContent} right
+   * @return {boolean}
+   */
+  mergeWith (right) {
+    throw error.methodUnimplemented()
+  }
+  /**
+   * @param {Transaction} transaction
+   * @param {Item} item
+   */
+  integrate (transaction, item) {
+    throw error.methodUnimplemented()
+  }
+  /**
+   * @param {Transaction} transaction
+   */
+  delete (transaction) {
+    throw error.methodUnimplemented()
+  }
+  /**
+   * @param {StructStore} store
+   */
+  gc (store) {
+    throw error.methodUnimplemented()
+  }
+  /**
+   * @param {encoding.Encoder} encoder
+   * @param {number} offset
+   */
+  write (encoder, offset) {
+    throw error.methodUnimplemented()
+  }
+  /**
+   * @return {number}
+   */
+  getRef () {
+    throw error.methodUnimplemented()
   }
 }
 
 /**
  * @private
  */
-export class AbstractItemRef extends AbstractStructRef {
+export class ItemRef extends AbstractStructRef {
   /**
    * @param {decoding.Decoder} decoder
    * @param {ID} id
@@ -553,79 +703,70 @@ export class AbstractItemRef extends AbstractStructRef {
     if (this.parent !== null) {
       missing.push(this.parent)
     }
+    /**
+     * @type {AbstractContent}
+     */
+    this.content = readItemContent(decoder, info)
+    this.length = this.content.getLength()
   }
-}
-
-/**
- * @param {AbstractItemRef} item
- * @param {number} offset
- *
- * @function
- * @private
- */
-export const changeItemRefOffset = (item, offset) => {
-  item.id = createID(item.id.client, item.id.clock + offset)
-  item.left = createID(item.id.client, item.id.clock - 1)
-}
-
-export class ItemParams {
   /**
-   * @param {AbstractItem?} left
-   * @param {AbstractItem?} right
-   * @param {AbstractType<YEvent>?} parent
-   * @param {string|null} parentSub
+   * @param {Transaction} transaction
+   * @param {StructStore} store
+   * @param {number} offset
+   * @return {Item|GC}
    */
-  constructor (left, right, parent, parentSub) {
-    this.left = left
-    this.right = right
-    this.parent = parent
-    this.parentSub = parentSub
-  }
-}
+  toStruct (transaction, store, offset) {
+    if (offset > 0) {
+      /**
+       * @type {ID}
+       */
+      const id = this.id
+      this.id = createID(id.client, id.clock + offset)
+      this.left = createID(this.id.client, this.id.clock - 1)
+      this.content = this.content.splice(offset)
+      this.length -= offset
+    }
 
-/**
- * Outsourcing some of the logic of computing the item params from a received struct.
- * If parent === null, it is expected to gc the read struct. Otherwise apply it.
- *
- * @param {Transaction} transaction
- * @param {StructStore} store
- * @param {ID|null} leftid
- * @param {ID|null} rightid
- * @param {ID|null} parentid
- * @param {string|null} parentSub
- * @param {string|null} parentYKey
- * @return {ItemParams}
- *
- * @private
- * @function
- */
-export const computeItemParams = (transaction, store, leftid, rightid, parentid, parentSub, parentYKey) => {
-  const left = leftid === null ? null : getItemCleanEnd(transaction, store, leftid)
-  const right = rightid === null ? null : getItemCleanStart(transaction, store, rightid)
-  let parent = null
-  if (parentid !== null) {
-    const parentItem = getItemType(store, parentid)
-    switch (parentItem.constructor) {
-      case ItemDeleted:
-      case GC:
-        break
-      default:
-        parent = parentItem.type
+    const left = this.left === null ? null : getItemCleanEnd(transaction, store, this.left)
+    const right = this.right === null ? null : getItemCleanStart(transaction, this.right)
+    let parent = null
+    let parentSub = this.parentSub
+    if (this.parent !== null) {
+      const parentItem = getItem(store, this.parent)
+      // Edge case: toStruct is called with an offset > 0. In this case left is defined.
+      // Depending in which order structs arrive, left may be GC'd and the parent not
+      // deleted. This is why we check if left is GC'd. Strictly we don't have
+      // to check if right is GC'd, but we will in case we run into future issues
+      if (!parentItem.deleted && (left === null || left.constructor !== GC) && (right === null || right.constructor !== GC)) {
+        parent = /** @type {ContentType} */ (parentItem.content).type
+      }
+    } else if (this.parentYKey !== null) {
+      parent = transaction.doc.get(this.parentYKey)
+    } else if (left !== null) {
+      if (left.constructor !== GC) {
+        parent = left.parent
+        parentSub = left.parentSub
+      }
+    } else if (right !== null) {
+      if (right.constructor !== GC) {
+        parent = right.parent
+        parentSub = right.parentSub
+      }
+    } else {
+      throw error.unexpectedCase()
     }
-  } else if (parentYKey !== null) {
-    parent = transaction.y.get(parentYKey)
-  } else if (left !== null) {
-    if (left.constructor !== GC) {
-      parent = left.parent
-      parentSub = left.parentSub
-    }
-  } else if (right !== null) {
-    if (right.constructor !== GC) {
-      parent = right.parent
-      parentSub = right.parentSub
-    }
-  } else {
-    throw error.unexpectedCase()
+
+    return parent === null
+      ? new GC(this.id, this.length)
+      : new Item(
+        this.id,
+        left,
+        this.left,
+        right,
+        this.right,
+        parent,
+        parentSub,
+        this.content
+      )
   }
-  return new ItemParams(left, right, parent, parentSub)
 }

src/structs/ItemBinary.js

@@ -1,98 +0,0 @@
-
-import {
-  AbstractItem,
-  AbstractItemRef,
-  computeItemParams,
-  GC,
-  StructStore, Transaction, AbstractType, ID // eslint-disable-line
-} from '../internals.js'
-
-import * as encoding from 'lib0/encoding.js'
-import * as decoding from 'lib0/decoding.js'
-
-/**
- * @private
- */
-export const structBinaryRefNumber = 1
-
-/**
- * @private
- */
-export class ItemBinary extends AbstractItem {
-  /**
-   * @param {ID} id
-   * @param {AbstractItem | null} left
-   * @param {ID | null} origin
-   * @param {AbstractItem | null} right
-   * @param {ID | null} rightOrigin
-   * @param {AbstractType<any>} parent
-   * @param {string | null} parentSub
-   * @param {ArrayBuffer} content
-   */
-  constructor (id, left, origin, right, rightOrigin, parent, parentSub, content) {
-    super(id, left, origin, right, rightOrigin, parent, parentSub)
-    this.content = content
-  }
-  getContent () {
-    return [this.content]
-  }
-  /**
-   * @param {ID} id
-   * @param {AbstractItem | null} left
-   * @param {ID | null} origin
-   * @param {AbstractItem | null} right
-   * @param {ID | null} rightOrigin
-   * @param {AbstractType<any>} parent
-   * @param {string | null} parentSub
-   */
-  copy (id, left, origin, right, rightOrigin, parent, parentSub) {
-    return new ItemBinary(id, left, origin, right, rightOrigin, parent, parentSub, this.content)
-  }
-  /**
-   * @param {encoding.Encoder} encoder
-   * @param {number} offset
-   */
-  write (encoder, offset) {
-    super.write(encoder, offset, structBinaryRefNumber)
-    encoding.writePayload(encoder, this.content)
-  }
-}
-
-/**
- * @private
- */
-export class ItemBinaryRef extends AbstractItemRef {
-  /**
-   * @param {decoding.Decoder} decoder
-   * @param {ID} id
-   * @param {number} info
-   */
-  constructor (decoder, id, info) {
-    super(decoder, id, info)
-    /**
-     * @type {ArrayBuffer}
-     */
-    this.content = decoding.readPayload(decoder)
-  }
-  /**
-   * @param {Transaction} transaction
-   * @param {StructStore} store
-   * @param {number} offset
-   * @return {ItemBinary|GC}
-   */
-  toStruct (transaction, store, offset) {
-    const { left, right, parent, parentSub } = computeItemParams(transaction, store, this.left, this.right, this.parent, this.parentSub, this.parentYKey)
-    return parent === null
-      ? new GC(this.id, this.length)
-      : new ItemBinary(
-        this.id,
-        left,
-        this.left,
-        right,
-        this.right,
-        parent,
-        parentSub,
-        this.content
-      )
-  }
-}

src/structs/ItemDeleted.js

@@ -1,142 +0,0 @@
-
-import {
-  AbstractItem,
-  AbstractItemRef,
-  computeItemParams,
-  changeItemRefOffset,
-  GC,
-  splitItem,
-  addToDeleteSet,
-  Y, StructStore, Transaction, ID, AbstractType // eslint-disable-line
-} from '../internals.js'
-
-import * as encoding from 'lib0/encoding.js'
-import * as decoding from 'lib0/decoding.js'
-
-/**
- * @private
- */
-export const structDeletedRefNumber = 2
-
-/**
- * @private
- */
-export class ItemDeleted extends AbstractItem {
-  /**
-   * @param {ID} id
-   * @param {AbstractItem | null} left
-   * @param {ID | null} origin
-   * @param {AbstractItem | null} right
-   * @param {ID | null} rightOrigin
-   * @param {AbstractType<any>} parent
-   * @param {string | null} parentSub
-   * @param {number} length
-   */
-  constructor (id, left, origin, right, rightOrigin, parent, parentSub, length) {
-    super(id, left, origin, right, rightOrigin, parent, parentSub)
-    this._len = length
-    this.deleted = true
-  }
-  get length () {
-    return this._len
-  }
-  /**
-   * @param {ID} id
-   * @param {AbstractItem | null} left
-   * @param {ID | null} origin
-   * @param {AbstractItem | null} right
-   * @param {ID | null} rightOrigin
-   * @param {AbstractType<any>} parent
-   * @param {string | null} parentSub
-   */
-  copy (id, left, origin, right, rightOrigin, parent, parentSub) {
-    return new ItemDeleted(id, left, origin, right, rightOrigin, parent, parentSub, this.length)
-  }
-  /**
-   * @param {Transaction} transaction
-   */
-  integrate (transaction) {
-    super.integrate(transaction)
-    addToDeleteSet(transaction.deleteSet, this.id, this.length)
-  }
-  /**
-   * @param {Transaction} transaction
-   * @param {number} diff
-   */
-  splitAt (transaction, diff) {
-    /**
-     * @type {ItemDeleted}
-     */
-    // @ts-ignore
-    const right = splitItem(transaction, this, diff)
-    right._len -= diff
-    this._len = diff
-    return right
-  }
-  /**
-   * @param {ItemDeleted} right
-   * @return {boolean}
-   */
-  mergeWith (right) {
-    if (super.mergeWith(right)) {
-      this._len += right._len
-      return true
-    }
-    return false
-  }
-  /**
-   * @param {encoding.Encoder} encoder
-   * @param {number} offset
-   */
-  write (encoder, offset) {
-    super.write(encoder, offset, structDeletedRefNumber)
-    encoding.writeVarUint(encoder, this.length - offset)
-  }
-}
-
-/**
- * @private
- */
-export class ItemDeletedRef extends AbstractItemRef {
-  /**
-   * @param {decoding.Decoder} decoder
-   * @param {ID} id
-   * @param {number} info
-   */
-  constructor (decoder, id, info) {
-    super(decoder, id, info)
-    /**
-     * @type {number}
-     */
-    this.len = decoding.readVarUint(decoder)
-  }
-  get length () {
-    return this.len
-  }
-  /**
-   * @param {Transaction} transaction
-   * @param {StructStore} store
-   * @param {number} offset
-   * @return {ItemDeleted|GC}
-   */
-  toStruct (transaction, store, offset) {
-    if (offset > 0) {
-      changeItemRefOffset(this, offset)
-      this.len = this.len - offset
-    }
-
-    const { left, right, parent, parentSub } = computeItemParams(transaction, store, this.left, this.right, this.parent, this.parentSub, this.parentYKey)
-    return parent === null
-      ? new GC(this.id, this.length)
-      : new ItemDeleted(
-        this.id,
-        left,
-        this.left,
-        right,
-        this.right,
-        parent,
-        parentSub,
-        this.len
-      )
-  }
-}

src/structs/ItemEmbed.js

@@ -1,95 +0,0 @@
-
-import {
-  AbstractItem,
-  AbstractItemRef,
-  computeItemParams,
-  GC,
-  Transaction, StructStore, ID, AbstractType // eslint-disable-line
-} from '../internals.js'
-
-import * as encoding from 'lib0/encoding.js'
-import * as decoding from 'lib0/decoding.js'
-
-/**
- * @private
- */
-export const structEmbedRefNumber = 3
-
-/**
- * @private
- */
-export class ItemEmbed extends AbstractItem {
-  /**
-   * @param {ID} id
-   * @param {AbstractItem | null} left
-   * @param {ID | null} origin
-   * @param {AbstractItem | null} right
-   * @param {ID | null} rightOrigin
-   * @param {AbstractType<any>} parent
-   * @param {string | null} parentSub
-   * @param {Object} embed
-   */
-  constructor (id, left, origin, right, rightOrigin, parent, parentSub, embed) {
-    super(id, left, origin, right, rightOrigin, parent, parentSub)
-    this.embed = embed
-  }
-  /**
-   * @param {ID} id
-   * @param {AbstractItem | null} left
-   * @param {ID | null} origin
-   * @param {AbstractItem | null} right
-   * @param {ID | null} rightOrigin
-   * @param {AbstractType<any>} parent
-   * @param {string | null} parentSub
-   */
-  copy (id, left, origin, right, rightOrigin, parent, parentSub) {
-    return new ItemEmbed(id, left, origin, right, rightOrigin, parent, parentSub, this.embed)
-  }
-  /**
-   * @param {encoding.Encoder} encoder
-   * @param {number} offset
-   */
-  write (encoder, offset) {
-    super.write(encoder, offset, structEmbedRefNumber)
-    encoding.writeVarString(encoder, JSON.stringify(this.embed))
-  }
-}
-
-/**
- * @private
- */
-export class ItemEmbedRef extends AbstractItemRef {
-  /**
-   * @param {decoding.Decoder} decoder
-   * @param {ID} id
-   * @param {number} info
-   */
-  constructor (decoder, id, info) {
-    super(decoder, id, info)
-    /**
-     * @type {ArrayBuffer}
-     */
-    this.embed = JSON.parse(decoding.readVarString(decoder))
-  }
-  /**
-   * @param {Transaction} transaction
-   * @param {StructStore} store
-   * @param {number} offset
-   * @return {ItemEmbed|GC}
-   */
-  toStruct (transaction, store, offset) {
-    const { left, right, parent, parentSub } = computeItemParams(transaction, store, this.left, this.right, this.parent, this.parentSub, this.parentYKey)
-    return parent === null
-      ? new GC(this.id, this.length)
-      : new ItemEmbed(
-        this.id,
-        left,
-        this.left,
-        right,
-        this.right,
-        parent,
-        parentSub,
-        this.embed
-      )
-  }
-}

src/structs/ItemFormat.js

@@ -1,103 +0,0 @@
-
-import {
-  AbstractItem,
-  AbstractItemRef,
-  computeItemParams,
-  GC,
-  Transaction, StructStore, ID, AbstractType // eslint-disable-line
-} from '../internals.js'
-
-import * as encoding from 'lib0/encoding.js'
-import * as decoding from 'lib0/decoding.js'
-
-/**
- * @private
- */
-export const structFormatRefNumber = 4
-
-/**
- * @private
- */
-export class ItemFormat extends AbstractItem {
-  /**
-   * @param {ID} id
-   * @param {AbstractItem | null} left
-   * @param {ID | null} origin
-   * @param {AbstractItem | null} right
-   * @param {ID | null} rightOrigin
-   * @param {AbstractType<any>} parent
-   * @param {string | null} parentSub
-   * @param {string} key
-   * @param {any} value
-   */
-  constructor (id, left, origin, right, rightOrigin, parent, parentSub, key, value) {
-    super(id, left, origin, right, rightOrigin, parent, parentSub)
-    this.key = key
-    this.value = value
-  }
-  /**
-   * @param {ID} id
-   * @param {AbstractItem | null} left
-   * @param {ID | null} origin
-   * @param {AbstractItem | null} right
-   * @param {ID | null} rightOrigin
-   * @param {AbstractType<any>} parent
-   * @param {string | null} parentSub
-   */
-  copy (id, left, origin, right, rightOrigin, parent, parentSub) {
-    return new ItemFormat(id, left, origin, right, rightOrigin, parent, parentSub, this.key, this.value)
-  }
-  get countable () {
-    return false
-  }
-  /**
-   * @param {encoding.Encoder} encoder
-   * @param {number} offset
-   */
-  write (encoder, offset) {
-    super.write(encoder, offset, structFormatRefNumber)
-    encoding.writeVarString(encoder, this.key)
-    encoding.writeVarString(encoder, JSON.stringify(this.value))
-  }
-}
-
-/**
- * @private
- */
-export class ItemFormatRef extends AbstractItemRef {
-  /**
-   * @param {decoding.Decoder} decoder
-   * @param {ID} id
-   * @param {number} info
-   */
-  constructor (decoder, id, info) {
-    super(decoder, id, info)
-    /**
-     * @type {string}
-     */
-    this.key = decoding.readVarString(decoder)
-    this.value = JSON.parse(decoding.readVarString(decoder))
-  }
-  /**
-   * @param {Transaction} transaction
-   * @param {StructStore} store
-   * @param {number} offset
-   * @return {ItemFormat|GC}
-   */
-  toStruct (transaction, store, offset) {
-    const { left, right, parent, parentSub } = computeItemParams(transaction, store, this.left, this.right, this.parent, this.parentSub, this.parentYKey)
-    return parent === null
-      ? new GC(this.id, this.length)
-      : new ItemFormat(
-        this.id,
-        left,
-        this.left,
-        right,
-        this.right,
-        parent,
-        parentSub,
-        this.key,
-        this.value
-      )
-  }
-}

src/structs/ItemJSON.js

@@ -1,152 +0,0 @@
-
-import {
-  AbstractItem,
-  AbstractItemRef,
-  computeItemParams,
-  splitItem,
-  changeItemRefOffset,
-  GC,
-  Transaction, StructStore, Y, ID, AbstractType // eslint-disable-line
-} from '../internals.js'
-
-import * as encoding from 'lib0/encoding.js'
-import * as decoding from 'lib0/decoding.js'
-
-/**
- * @private
- */
-export const structJSONRefNumber = 5
-
-/**
- * @private
- */
-export class ItemJSON extends AbstractItem {
-  /**
-   * @param {ID} id
-   * @param {AbstractItem | null} left
-   * @param {ID | null} origin
-   * @param {AbstractItem | null} right
-   * @param {ID | null} rightOrigin
-   * @param {AbstractType<any>} parent
-   * @param {string | null} parentSub
-   * @param {Array<any>} content
-   */
-  constructor (id, left, origin, right, rightOrigin, parent, parentSub, content) {
-    super(id, left, origin, right, rightOrigin, parent, parentSub)
-    /**
-     * @type {Array<any>}
-     */
-    this.content = content
-  }
-  /**
-   * @param {ID} id
-   * @param {AbstractItem | null} left
-   * @param {ID | null} origin
-   * @param {AbstractItem | null} right
-   * @param {ID | null} rightOrigin
-   * @param {AbstractType<any>} parent
-   * @param {string | null} parentSub
-   */
-  copy (id, left, origin, right, rightOrigin, parent, parentSub) {
-    return new ItemJSON(id, left, origin, right, rightOrigin, parent, parentSub, this.content)
-  }
-  get length () {
-    return this.content.length
-  }
-  getContent () {
-    return this.content
-  }
-  /**
-   * @param {Transaction} transaction
-   * @param {number} diff
-   */
-  splitAt (transaction, diff) {
-    /**
-     * @type {ItemJSON}
-     */
-    // @ts-ignore
-    const right = splitItem(transaction, this, diff)
-    right.content = this.content.splice(diff)
-    return right
-  }
-  /**
-   * @param {ItemJSON} right
-   * @return {boolean}
-   */
-  mergeWith (right) {
-    if (super.mergeWith(right)) {
-      this.content = this.content.concat(right.content)
-      return true
-    }
-    return false
-  }
-  /**
-   * @param {encoding.Encoder} encoder
-   * @param {number} offset
-   */
-  write (encoder, offset) {
-    super.write(encoder, offset, structJSONRefNumber)
-    const len = this.content.length
-    encoding.writeVarUint(encoder, len - offset)
-    for (let i = offset; i < len; i++) {
-      const c = this.content[i]
-      encoding.writeVarString(encoder, c === undefined ? 'undefined' : JSON.stringify(c))
-    }
-  }
-}
-
-/**
- * @private
- */
-export class ItemJSONRef extends AbstractItemRef {
-  /**
-   * @param {decoding.Decoder} decoder
-   * @param {ID} id
-   * @param {number} info
-   */
-  constructor (decoder, id, info) {
-    super(decoder, id, info)
-    const len = decoding.readVarUint(decoder)
-    const cs = []
-    for (let i = 0; i < len; i++) {
-      const c = decoding.readVarString(decoder)
-      if (c === 'undefined') {
-        cs.push(undefined)
-      } else {
-        cs.push(JSON.parse(c))
-      }
-    }
-    /**
-     * @type {Array<any>}
-     */
-    this.content = cs
-  }
-  get length () {
-    return this.content.length
-  }
-  /**
-   * @param {Transaction} transaction
-   * @param {StructStore} store
-   * @param {number} offset
-   * @return {ItemJSON|GC}
-   */
-  toStruct (transaction, store, offset) {
-    if (offset > 0) {
-      changeItemRefOffset(this, offset)
-      this.content = this.content.slice(offset)
-    }
-    const { left, right, parent, parentSub } = computeItemParams(transaction, store, this.left, this.right, this.parent, this.parentSub, this.parentYKey)
-    return parent === null
-      ? new GC(this.id, this.length)
-      : new ItemJSON(
-        this.id,
-        left,
-        this.left,
-        right,
-        this.right,
-        parent,
-        parentSub,
-        this.content
-      )
-  }
-}

src/structs/ItemString.js

@@ -1,137 +0,0 @@
-
-import {
-  AbstractItem,
-  AbstractItemRef,
-  computeItemParams,
-  splitItem,
-  changeItemRefOffset,
-  GC,
-  Transaction, StructStore, Y, ID, AbstractType // eslint-disable-line
-} from '../internals.js'
-
-import * as encoding from 'lib0/encoding.js'
-import * as decoding from 'lib0/decoding.js'
-
-export const structStringRefNumber = 6
-
-/**
- * @private
- */
-export class ItemString extends AbstractItem {
-  /**
-   * @param {ID} id
-   * @param {AbstractItem | null} left
-   * @param {ID | null} origin
-   * @param {AbstractItem | null} right
-   * @param {ID | null} rightOrigin
-   * @param {AbstractType<any>} parent
-   * @param {string | null} parentSub
-   * @param {string} string
-   */
-  constructor (id, left, origin, right, rightOrigin, parent, parentSub, string) {
-    super(id, left, origin, right, rightOrigin, parent, parentSub)
-    /**
-     * @type {string}
-     */
-    this.string = string
-  }
-  /**
-   * @param {ID} id
-   * @param {AbstractItem | null} left
-   * @param {ID | null} origin
-   * @param {AbstractItem | null} right
-   * @param {ID | null} rightOrigin
-   * @param {AbstractType<any>} parent
-   * @param {string | null} parentSub
-   */
-  copy (id, left, origin, right, rightOrigin, parent, parentSub) {
-    return new ItemString(id, left, origin, right, rightOrigin, parent, parentSub, this.string)
-  }
-  getContent () {
-    return this.string.split('')
-  }
-  get length () {
-    return this.string.length
-  }
-  /**
-   * @param {Transaction} transaction
-   * @param {number} diff
-   * @return {ItemString}
-   */
-  splitAt (transaction, diff) {
-    /**
-     * @type {ItemString}
-     */
-    // @ts-ignore
-    const right = splitItem(transaction, this, diff)
-    right.string = this.string.slice(diff)
-    this.string = this.string.slice(0, diff)
-    return right
-  }
-  /**
-   * @param {ItemString} right
-   * @return {boolean}
-   */
-  mergeWith (right) {
-    if (super.mergeWith(right)) {
-      this.string += right.string
-      return true
-    }
-    return false
-  }
-  /**
-   * @param {encoding.Encoder} encoder
-   * @param {number} offset
-   */
-  write (encoder, offset) {
-    super.write(encoder, offset, structStringRefNumber)
-    encoding.writeVarString(encoder, offset === 0 ? this.string : this.string.slice(offset))
-  }
-}
-
-/**
- * @private
- */
-export class ItemStringRef extends AbstractItemRef {
-  /**
-   * @param {decoding.Decoder} decoder
-   * @param {ID} id
-   * @param {number} info
-   */
-  constructor (decoder, id, info) {
-    super(decoder, id, info)
-    /**
-     * @type {string}
-     */
-    this.string = decoding.readVarString(decoder)
-  }
-  get length () {
-    return this.string.length
-  }
-  /**
-   * @param {Transaction} transaction
-   * @param {StructStore} store
-   * @param {number} offset
-   * @return {ItemString|GC}
-   */
-  toStruct (transaction, store, offset) {
-    if (offset > 0) {
-      changeItemRefOffset(this, offset)
-      this.string = this.string.slice(offset)
-    }
-
-    const { left, right, parent, parentSub } = computeItemParams(transaction, store, this.left, this.right, this.parent, this.parentSub, this.parentYKey)
-    return parent === null
-      ? new GC(this.id, this.length)
-      : new ItemString(
-        this.id,
-        left,
-        this.left,
-        right,
-        this.right,
-        parent,
-        parentSub,
-        this.string
-      )
-  }
-}

src/structs/ItemType.js

@@ -1,178 +0,0 @@
-
-import {
-  AbstractItem,
-  AbstractItemRef,
-  computeItemParams,
-  readYArray,
-  readYMap,
-  readYText,
-  readYXmlElement,
-  readYXmlFragment,
-  readYXmlHook,
-  readYXmlText,
-  StructStore, Y, GC, Transaction, ID, AbstractType // eslint-disable-line
-} from '../internals.js'
-
-import * as encoding from 'lib0/encoding.js' // eslint-disable-line
-import * as decoding from 'lib0/decoding.js'
-
-/**
- * @private
- */
-export const structTypeRefNumber = 7
-
-/**
- * @type {Array<function(decoding.Decoder):AbstractType<any>>}
- * @private
- */
-export const typeRefs = [
-  readYArray,
-  readYMap,
-  readYText,
-  readYXmlElement,
-  readYXmlFragment,
-  readYXmlHook,
-  readYXmlText
-]
-
-export const YArrayRefID = 0
-export const YMapRefID = 1
-export const YTextRefID = 2
-export const YXmlElementRefID = 3
-export const YXmlFragmentRefID = 4
-export const YXmlHookRefID = 5
-export const YXmlTextRefID = 6
-
-/**
- * @private
- */
-export class ItemType extends AbstractItem {
-  /**
-   * @param {ID} id
-   * @param {AbstractItem | null} left
-   * @param {ID | null} origin
-   * @param {AbstractItem | null} right
-   * @param {ID | null} rightOrigin
-   * @param {AbstractType<any>} parent
-   * @param {string | null} parentSub
-   * @param {AbstractType<any>} type
-   */
-  constructor (id, left, origin, right, rightOrigin, parent, parentSub, type) {
-    super(id, left, origin, right, rightOrigin, parent, parentSub)
-    this.type = type
-  }
-
-  getContent () {
-    return [this.type]
-  }
-  /**
-   * @param {ID} id
-   * @param {AbstractItem | null} left
-   * @param {ID | null} origin
-   * @param {AbstractItem | null} right
-   * @param {ID | null} rightOrigin
-   * @param {AbstractType<any>} parent
-   * @param {string | null} parentSub
-   * @return {ItemType}
-   */
-  copy (id, left, origin, right, rightOrigin, parent, parentSub) {
-    return new ItemType(id, left, origin, right, rightOrigin, parent, parentSub, this.type._copy())
-  }
-  /**
-   * @param {Transaction} transaction
-   */
-  integrate (transaction) {
-    super.integrate(transaction)
-    this.type._integrate(transaction.y, this)
-  }
-  /**
-   * @param {encoding.Encoder} encoder
-   * @param {number} offset
-   */
-  write (encoder, offset) {
-    super.write(encoder, offset, structTypeRefNumber)
-    this.type._write(encoder)
-  }
-  /**
-   * Mark this Item as deleted.
-   *
-   * @param {Transaction} transaction The Yjs instance
-   * @private
-   */
-  delete (transaction) {
-    super.delete(transaction)
-    transaction.changed.delete(this.type)
-    transaction.changedParentTypes.delete(this.type)
-    this.gcChildren(transaction, transaction.y.store)
-  }
-
-  /**
-   * @param {Transaction} transaction
-   * @param {StructStore} store
-   */
-  gcChildren (transaction, store) {
-    let item = this.type._start
-    while (item !== null) {
-      item.gc(transaction, store)
-      item = item.right
-    }
-    this.type._start = null
-    this.type._map.forEach(item => {
-      while (item !== null) {
-        item.gc(transaction, store)
-        // @ts-ignore
-        item = item.left
-      }
-    })
-    this._map = new Map()
-  }
-
-  /**
-   * @param {Transaction} transaction
-   * @param {StructStore} store
-   */
-  gc (transaction, store) {
-    super.gc(transaction, store)
-    this.gcChildren(transaction, store)
-  }
-}
-
-/**
- * @private
- */
-export class ItemTypeRef extends AbstractItemRef {
-  /**
-   * @param {decoding.Decoder} decoder
-   * @param {ID} id
-   * @param {number} info
-   */
-  constructor (decoder, id, info) {
-    super(decoder, id, info)
-    const typeRef = decoding.readVarUint(decoder)
-    /**
-     * @type {AbstractType<any>}
-     */
-    this.type = typeRefs[typeRef](decoder)
-  }
-  /**
-   * @param {Transaction} transaction
-   * @param {StructStore} store
-   * @param {number} offset
-   * @return {ItemType|GC}
-   */
-  toStruct (transaction, store, offset) {
-    const { left, right, parent, parentSub } = computeItemParams(transaction, store, this.left, this.right, this.parent, this.parentSub, this.parentYKey)
-    return parent === null
-      ? new GC(this.id, this.length)
-      : new ItemType(
-        this.id,
-        left,
-        this.left,
-        right,
-        this.right,
-        parent,
-        parentSub,
-        this.type
-      )
-  }
-}

src/types/AbstractType.js

@@ -4,14 +4,14 @@ import {
   callEventHandlerListeners,
   addEventHandlerListener,
   createEventHandler,
-  ItemType,
   nextID,
   isVisible,
-  ItemJSON,
-  ItemBinary,
+  ContentType,
+  ContentAny,
+  ContentBinary,
   createID,
   getItemCleanStart,
-  Y, Snapshot, Transaction, EventHandler, YEvent, AbstractItem, // eslint-disable-line
+  Doc, Snapshot, Transaction, EventHandler, YEvent, Item, // eslint-disable-line
 } from '../internals.js'
 
 import * as map from 'lib0/map.js'
@@ -30,7 +30,7 @@ import * as encoding from 'lib0/encoding.js' // eslint-disable-line
  * @param {EventType} event
  */
 export const callTypeObservers = (type, transaction, event) => {
-  callEventHandlerListeners(type._eH, event, transaction)
+  const changedType = type
   const changedParentTypes = transaction.changedParentTypes
   while (true) {
     // @ts-ignore
@@ -40,6 +40,7 @@ export const callTypeObservers = (type, transaction, event) => {
     }
     type = type._item.parent
   }
+  callEventHandlerListeners(changedType._eH, event, transaction)
 }
 
 /**
@@ -49,24 +50,24 @@ export const callTypeObservers = (type, transaction, event) => {
 export class AbstractType {
   constructor () {
     /**
-     * @type {ItemType|null}
+     * @type {Item|null}
      */
     this._item = null
     /**
      * @private
-     * @type {Map<string,AbstractItem>}
+     * @type {Map<string,Item>}
      */
     this._map = new Map()
     /**
      * @private
-     * @type {AbstractItem|null}
+     * @type {Item|null}
      */
     this._start = null
     /**
      * @private
-     * @type {Y|null}
+     * @type {Doc|null}
      */
-    this._y = null
+    this.doc = null
     this._length = 0
     /**
      * Event handlers
@@ -87,12 +88,12 @@ export class AbstractType {
    * * This type is sent to other client
    * * Observer functions are fired
    *
-   * @param {Y} y The Yjs instance
-   * @param {ItemType|null} item
+   * @param {Doc} y The Yjs instance
+   * @param {Item|null} item
    * @private
    */
   _integrate (y, item) {
-    this._y = y
+    this.doc = y
     this._item = item
   }
 
@@ -101,7 +102,7 @@ export class AbstractType {
    * @private
    */
   _copy () {
-    throw new Error('unimplemented')
+    throw error.methodUnimplemented()
   }
 
   /**
@@ -182,12 +183,35 @@ export class AbstractType {
  * @private
  * @function
  */
-export const typeArrayToArray = type => {
+export const typeListToArray = type => {
   const cs = []
   let n = type._start
   while (n !== null) {
     if (n.countable && !n.deleted) {
-      const c = n.getContent()
+      const c = n.content.getContent()
+      for (let i = 0; i < c.length; i++) {
+        cs.push(c[i])
+      }
+    }
+    n = n.right
+  }
+  return cs
+}
+
+/**
+ * @param {AbstractType<any>} type
+ * @param {Snapshot} snapshot
+ * @return {Array<any>}
+ *
+ * @private
+ * @function
+ */
+export const typeListToArraySnapshot = (type, snapshot) => {
+  const cs = []
+  let n = type._start
+  while (n !== null) {
+    if (n.countable && isVisible(n, snapshot)) {
+      const c = n.content.getContent()
       for (let i = 0; i < c.length; i++) {
         cs.push(c[i])
       }
@@ -201,17 +225,17 @@ export const typeArrayToArray = type => {
  * Executes a provided function on once on overy element of this YArray.
  *
  * @param {AbstractType<any>} type
- * @param {function(any,number,AbstractType<any>):void} f A function to execute on every element of this YArray.
+ * @param {function(any,number,any):void} f A function to execute on every element of this YArray.
  *
  * @private
  * @function
  */
-export const typeArrayForEach = (type, f) => {
+export const typeListForEach = (type, f) => {
   let index = 0
   let n = type._start
   while (n !== null) {
     if (n.countable && !n.deleted) {
-      const c = n.getContent()
+      const c = n.content.getContent()
       for (let i = 0; i < c.length; i++) {
         f(c[i], index++, type)
       }
@@ -229,12 +253,12 @@ export const typeArrayForEach = (type, f) => {
  * @private
  * @function
  */
-export const typeArrayMap = (type, f) => {
+export const typeListMap = (type, f) => {
   /**
    * @type {Array<any>}
    */
   const result = []
-  typeArrayForEach(type, (c, i) => {
+  typeListForEach(type, (c, i) => {
     result.push(f(c, i, type))
   })
   return result
@@ -247,7 +271,7 @@ export const typeArrayMap = (type, f) => {
  * @private
  * @function
  */
-export const typeArrayCreateIterator = type => {
+export const typeListCreateIterator = type => {
   let n = type._start
   /**
    * @type {Array<any>|null}
@@ -264,18 +288,15 @@ export const typeArrayCreateIterator = type => {
         while (n !== null && n.deleted) {
           n = n.right
         }
-      }
-      // check if we reached the end, no need to check currentContent, because it does not exist
-      if (n === null) {
-        return {
-          done: true,
-          value: undefined
+        // check if we reached the end, no need to check currentContent, because it does not exist
+        if (n === null) {
+          return {
+            done: true,
+            value: undefined
+          }
         }
-      }
-      // currentContent could exist from the last iteration
-      if (currentContent === null) {
         // we found n, so we can set currentContent
-        currentContent = n.getContent()
+        currentContent = n.content.getContent()
         currentContentIndex = 0
         n = n.right // we used the content of n, now iterate to next
       }
@@ -303,12 +324,12 @@ export const typeArrayCreateIterator = type => {
  * @private
  * @function
  */
-export const typeArrayForEachSnapshot = (type, f, snapshot) => {
+export const typeListForEachSnapshot = (type, f, snapshot) => {
   let index = 0
   let n = type._start
   while (n !== null) {
     if (n.countable && isVisible(n, snapshot)) {
-      const c = n.getContent()
+      const c = n.content.getContent()
       for (let i = 0; i < c.length; i++) {
         f(c[i], index++, type)
       }
@@ -325,11 +346,11 @@ export const typeArrayForEachSnapshot = (type, f, snapshot) => {
  * @private
  * @function
  */
-export const typeArrayGet = (type, index) => {
+export const typeListGet = (type, index) => {
   for (let n = type._start; n !== null; n = n.right) {
     if (!n.deleted && n.countable) {
       if (index < n.length) {
-        return n.getContent()[index]
+        return n.content.getContent()[index]
       }
       index -= n.length
     }
@@ -339,13 +360,13 @@ export const typeArrayGet = (type, index) => {
 /**
  * @param {Transaction} transaction
  * @param {AbstractType<any>} parent
- * @param {AbstractItem?} referenceItem
- * @param {Array<Object<string,any>|Array<any>|number|string|ArrayBuffer>} content
+ * @param {Item?} referenceItem
+ * @param {Array<Object<string,any>|Array<any>|boolean|number|string|Uint8Array>} content
  *
  * @private
  * @function
  */
-export const typeArrayInsertGenericsAfter = (transaction, parent, referenceItem, content) => {
+export const typeListInsertGenericsAfter = (transaction, parent, referenceItem, content) => {
   let left = referenceItem
   const right = referenceItem === null ? parent._start : referenceItem.right
   /**
@@ -354,7 +375,7 @@ export const typeArrayInsertGenericsAfter = (transaction, parent, referenceItem,
   let jsonContent = []
   const packJsonContent = () => {
     if (jsonContent.length > 0) {
-      left = new ItemJSON(nextID(transaction), left, left === null ? null : left.lastId, right, right === null ? null : right.id, parent, null, jsonContent)
+      left = new Item(nextID(transaction), left, left === null ? null : left.lastId, right, right === null ? null : right.id, parent, null, new ContentAny(jsonContent))
       left.integrate(transaction)
       jsonContent = []
     }
@@ -363,6 +384,7 @@ export const typeArrayInsertGenericsAfter = (transaction, parent, referenceItem,
     switch (c.constructor) {
       case Number:
       case Object:
+      case Boolean:
       case Array:
       case String:
         jsonContent.push(c)
@@ -370,15 +392,14 @@ export const typeArrayInsertGenericsAfter = (transaction, parent, referenceItem,
       default:
         packJsonContent()
         switch (c.constructor) {
+          case Uint8Array:
           case ArrayBuffer:
-            // @ts-ignore c is definitely an ArrayBuffer
-            left = new ItemBinary(nextID(transaction), left, left === null ? null : left.lastId, right, right === null ? null : right.id, parent, null, c)
-            // @ts-ignore
+            left = new Item(nextID(transaction), left, left === null ? null : left.lastId, right, right === null ? null : right.id, parent, null, new ContentBinary(new Uint8Array(/** @type {Uint8Array} */ (c))))
             left.integrate(transaction)
             break
           default:
             if (c instanceof AbstractType) {
-              left = new ItemType(nextID(transaction), left, left === null ? null : left.lastId, right, right === null ? null : right.id, parent, null, c)
+              left = new Item(nextID(transaction), left, left === null ? null : left.lastId, right, right === null ? null : right.id, parent, null, new ContentType(c))
               left.integrate(transaction)
             } else {
               throw new Error('Unexpected content type in insert operation')
@@ -393,14 +414,14 @@ export const typeArrayInsertGenericsAfter = (transaction, parent, referenceItem,
  * @param {Transaction} transaction
  * @param {AbstractType<any>} parent
  * @param {number} index
- * @param {Array<Object<string,any>|Array<any>|number|string|ArrayBuffer>} content
+ * @param {Array<Object<string,any>|Array<any>|number|string|Uint8Array>} content
  *
  * @private
  * @function
  */
-export const typeArrayInsertGenerics = (transaction, parent, index, content) => {
+export const typeListInsertGenerics = (transaction, parent, index, content) => {
   if (index === 0) {
-    return typeArrayInsertGenericsAfter(transaction, parent, null, content)
+    return typeListInsertGenericsAfter(transaction, parent, null, content)
   }
   let n = parent._start
   for (; n !== null; n = n.right) {
@@ -408,14 +429,14 @@ export const typeArrayInsertGenerics = (transaction, parent, index, content) =>
       if (index <= n.length) {
         if (index < n.length) {
           // insert in-between
-          getItemCleanStart(transaction, transaction.y.store, createID(n.id.client, n.id.clock + index))
+          getItemCleanStart(transaction, createID(n.id.client, n.id.clock + index))
         }
         break
       }
       index -= n.length
     }
   }
-  return typeArrayInsertGenericsAfter(transaction, parent, n, content)
+  return typeListInsertGenericsAfter(transaction, parent, n, content)
 }
 
 /**
@@ -427,17 +448,14 @@ export const typeArrayInsertGenerics = (transaction, parent, index, content) =>
  * @private
  * @function
  */
-export const typeArrayDelete = (transaction, parent, index, length) => {
+export const typeListDelete = (transaction, parent, index, length) => {
   if (length === 0) { return }
   let n = parent._start
   // compute the first item to be deleted
-  for (; n !== null; n = n.right) {
+  for (; n !== null && index > 0; n = n.right) {
     if (!n.deleted && n.countable) {
-      if (index <= n.length) {
-        if (index < n.length && index > 0) {
-          n = getItemCleanStart(transaction, transaction.y.store, createID(n.id.client, n.id.clock + index))
-        }
-        break
+      if (index < n.length) {
+        getItemCleanStart(transaction, createID(n.id.client, n.id.clock + index))
       }
       index -= n.length
     }
@@ -446,7 +464,7 @@ export const typeArrayDelete = (transaction, parent, index, length) => {
   while (length > 0 && n !== null) {
     if (!n.deleted) {
       if (length < n.length) {
-        getItemCleanStart(transaction, transaction.y.store, createID(n.id.client, n.id.clock + length))
+        getItemCleanStart(transaction, createID(n.id.client, n.id.clock + length))
       }
       n.delete(transaction)
       length -= n.length
@@ -477,52 +495,55 @@ export const typeMapDelete = (transaction, parent, key) => {
  * @param {Transaction} transaction
  * @param {AbstractType<any>} parent
  * @param {string} key
- * @param {Object|number|Array<any>|string|ArrayBuffer|AbstractType<any>} value
+ * @param {Object|number|Array<any>|string|Uint8Array|AbstractType<any>} value
  *
  * @private
  * @function
  */
 export const typeMapSet = (transaction, parent, key, value) => {
   const left = parent._map.get(key) || null
+  let content
   if (value == null) {
-    new ItemJSON(nextID(transaction), left, left === null ? null : left.lastId, null, null, parent, key, [value]).integrate(transaction)
-    return
-  }
-  switch (value.constructor) {
-    case Number:
-    case Object:
-    case Array:
-    case String:
-      new ItemJSON(nextID(transaction), left, left === null ? null : left.lastId, null, null, parent, key, [value]).integrate(transaction)
-      break
-    case ArrayBuffer:
-      new ItemBinary(nextID(transaction), left, left === null ? null : left.lastId, null, null, parent, key, value).integrate(transaction)
-      break
-    default:
-      if (value instanceof AbstractType) {
-        new ItemType(nextID(transaction), left, left === null ? null : left.lastId, null, null, parent, key, value).integrate(transaction)
-      } else {
-        throw new Error('Unexpected content type')
-      }
+    content = new ContentAny([value])
+  } else {
+    switch (value.constructor) {
+      case Number:
+      case Object:
+      case Boolean:
+      case Array:
+      case String:
+        content = new ContentAny([value])
+        break
+      case Uint8Array:
+        content = new ContentBinary(value)
+        break
+      default:
+        if (value instanceof AbstractType) {
+          content = new ContentType(value)
+        } else {
+          throw new Error('Unexpected content type')
+        }
+    }
   }
+  new Item(nextID(transaction), left, left === null ? null : left.lastId, null, null, parent, key, content).integrate(transaction)
 }
 
 /**
  * @param {AbstractType<any>} parent
  * @param {string} key
- * @return {Object<string,any>|number|Array<any>|string|ArrayBuffer|AbstractType<any>|undefined}
+ * @return {Object<string,any>|number|Array<any>|string|Uint8Array|AbstractType<any>|undefined}
  *
  * @private
  * @function
  */
 export const typeMapGet = (parent, key) => {
   const val = parent._map.get(key)
-  return val !== undefined && !val.deleted ? val.getContent()[0] : undefined
+  return val !== undefined && !val.deleted ? val.content.getContent()[val.length - 1] : undefined
 }
 
 /**
  * @param {AbstractType<any>} parent
- * @return {Object<string,Object<string,any>|number|Array<any>|string|ArrayBuffer|AbstractType<any>|undefined>}
+ * @return {Object<string,Object<string,any>|number|Array<any>|string|Uint8Array|AbstractType<any>|undefined>}
  *
  * @private
  * @function
@@ -534,7 +555,7 @@ export const typeMapGetAll = (parent) => {
   let res = {}
   for (const [key, value] of parent._map) {
     if (!value.deleted) {
-      res[key] = value.getContent()[value.length - 1]
+      res[key] = value.content.getContent()[value.length - 1]
     }
   }
   return res
@@ -557,24 +578,24 @@ export const typeMapHas = (parent, key) => {
  * @param {AbstractType<any>} parent
  * @param {string} key
  * @param {Snapshot} snapshot
- * @return {Object<string,any>|number|Array<any>|string|ArrayBuffer|AbstractType<any>|undefined}
+ * @return {Object<string,any>|number|Array<any>|string|Uint8Array|AbstractType<any>|undefined}
  *
  * @private
  * @function
  */
 export const typeMapGetSnapshot = (parent, key, snapshot) => {
   let v = parent._map.get(key) || null
-  while (v !== null && (!snapshot.sm.has(v.id.client) || v.id.clock >= (snapshot.sm.get(v.id.client) || 0))) {
+  while (v !== null && (!snapshot.sv.has(v.id.client) || v.id.clock >= (snapshot.sv.get(v.id.client) || 0))) {
     v = v.left
   }
-  return v !== null && isVisible(v, snapshot) ? v.getContent()[v.length - 1] : undefined
+  return v !== null && isVisible(v, snapshot) ? v.content.getContent()[v.length - 1] : undefined
 }
 
 /**
- * @param {Map<string,AbstractItem>} map
+ * @param {Map<string,Item>} map
  * @return {IterableIterator<Array<any>>}
  *
  * @private
  * @function
  */
-export const createMapIterator = map => iterator.iteratorFilter(map.entries(), entry => !entry[1].deleted)
+export const createMapIterator = map => iterator.iteratorFilter(map.entries(), /** @param {any} entry */ entry => !entry[1].deleted)

src/types/YArray.js

@@ -5,17 +5,17 @@
 import {
   YEvent,
   AbstractType,
-  typeArrayGet,
-  typeArrayToArray,
-  typeArrayForEach,
-  typeArrayCreateIterator,
-  typeArrayInsertGenerics,
-  typeArrayDelete,
-  typeArrayMap,
+  typeListGet,
+  typeListToArray,
+  typeListForEach,
+  typeListCreateIterator,
+  typeListInsertGenerics,
+  typeListDelete,
+  typeListMap,
   YArrayRefID,
   callTypeObservers,
   transact,
-  Y, Transaction, ItemType, // eslint-disable-line
+  Doc, Transaction, Item // eslint-disable-line
 } from '../internals.js'
 
 import * as decoding from 'lib0/decoding.js' // eslint-disable-line
@@ -58,17 +58,21 @@ export class YArray extends AbstractType {
    * * This type is sent to other client
    * * Observer functions are fired
    *
-   * @param {Y} y The Yjs instance
-   * @param {ItemType} item
+   * @param {Doc} y The Yjs instance
+   * @param {Item} item
    *
    * @private
    */
   _integrate (y, item) {
     super._integrate(y, item)
-    // @ts-ignore
-    this.insert(0, this._prelimContent)
+    this.insert(0, /** @type {Array} */ (this._prelimContent))
     this._prelimContent = null
   }
+
+  _copy () {
+    return new YArray()
+  }
+
   get length () {
     return this._prelimContent === null ? this._length : this._prelimContent.length
   }
@@ -84,6 +88,57 @@ export class YArray extends AbstractType {
     callTypeObservers(this, transaction, new YArrayEvent(this, transaction))
   }
 
+  /**
+   * Inserts new content at an index.
+   *
+   * Important: This function expects an array of content. Not just a content
+   * object. The reason for this "weirdness" is that inserting several elements
+   * is very efficient when it is done as a single operation.
+   *
+   * @example
+   *  // Insert character 'a' at position 0
+   *  yarray.insert(0, ['a'])
+   *  // Insert numbers 1, 2 at position 1
+   *  yarray.insert(1, [1, 2])
+   *
+   * @param {number} index The index to insert content at.
+   * @param {Array<T>} content The array of content
+   */
+  insert (index, content) {
+    if (this.doc !== null) {
+      transact(this.doc, transaction => {
+        typeListInsertGenerics(transaction, this, index, content)
+      })
+    } else {
+      /** @type {Array} */ (this._prelimContent).splice(index, 0, ...content)
+    }
+  }
+
+  /**
+   * Appends content to this YArray.
+   *
+   * @param {Array<T>} content Array of content to append.
+   */
+  push (content) {
+    this.insert(this.length, content)
+  }
+
+  /**
+   * Deletes elements starting from an index.
+   *
+   * @param {number} index Index at which to start deleting elements
+   * @param {number} length The number of elements to remove. Defaults to 1.
+   */
+  delete (index, length = 1) {
+    if (this.doc !== null) {
+      transact(this.doc, transaction => {
+        typeListDelete(transaction, this, index, length)
+      })
+    } else {
+      /** @type {Array} */ (this._prelimContent).splice(index, length)
+    }
+  }
+
   /**
    * Returns the i-th element from a YArray.
    *
@@ -91,7 +146,7 @@ export class YArray extends AbstractType {
    * @return {T}
    */
   get (index) {
-    return typeArrayGet(this, index)
+    return typeListGet(this, index)
   }
 
   /**
@@ -100,7 +155,7 @@ export class YArray extends AbstractType {
    * @return {Array<T>}
    */
   toArray () {
-    return typeArrayToArray(this)
+    return typeListToArray(this)
   }
 
   /**
@@ -122,77 +177,23 @@ export class YArray extends AbstractType {
    *                 callback function
    */
   map (f) {
-    // @ts-ignore
-    return typeArrayMap(this, f)
+    return typeListMap(this, /** @type {any} */ (f))
   }
 
   /**
    * Executes a provided function on once on overy element of this YArray.
    *
-   * @param {function(T,number):void} f A function to execute on every element of this YArray.
+   * @param {function(T,number,YArray<T>):void} f A function to execute on every element of this YArray.
    */
   forEach (f) {
-    typeArrayForEach(this, f)
+    typeListForEach(this, f)
   }
 
   /**
    * @return {IterableIterator<T>}
    */
   [Symbol.iterator] () {
-    return typeArrayCreateIterator(this)
-  }
-
-  /**
-   * Deletes elements starting from an index.
-   *
-   * @param {number} index Index at which to start deleting elements
-   * @param {number} length The number of elements to remove. Defaults to 1.
-   */
-  delete (index, length = 1) {
-    if (this._y !== null) {
-      transact(this._y, transaction => {
-        typeArrayDelete(transaction, this, index, length)
-      })
-    } else {
-      // @ts-ignore _prelimContent is defined because this is not yet integrated
-      this._prelimContent.splice(index, length)
-    }
-  }
-
-  /**
-   * Inserts new content at an index.
-   *
-   * Important: This function expects an array of content. Not just a content
-   * object. The reason for this "weirdness" is that inserting several elements
-   * is very efficient when it is done as a single operation.
-   *
-   * @example
-   *  // Insert character 'a' at position 0
-   *  yarray.insert(0, ['a'])
-   *  // Insert numbers 1, 2 at position 1
-   *  yarray.insert(1, [1, 2])
-   *
-   * @param {number} index The index to insert content at.
-   * @param {Array<T>} content The array of content
-   */
-  insert (index, content) {
-    if (this._y !== null) {
-      transact(this._y, transaction => {
-        typeArrayInsertGenerics(transaction, this, index, content)
-      })
-    } else {
-      // @ts-ignore _prelimContent is defined because this is not yet integrated
-      this._prelimContent.splice(index, 0, ...content)
-    }
-  }
-
-  /**
-   * Appends content to this YArray.
-   *
-   * @param {Array<T>} content Array of content to append.
-   */
-  push (content) {
-    this.insert(this.length, content)
+    return typeListCreateIterator(this)
   }
 
   /**

src/types/YMap.js

@@ -14,7 +14,7 @@ import {
   YMapRefID,
   callTypeObservers,
   transact,
-  Y, Transaction, ItemType, // eslint-disable-line
+  Doc, Transaction, Item // eslint-disable-line
 } from '../internals.js'
 
 import * as encoding from 'lib0/encoding.js'
@@ -38,7 +38,7 @@ export class YMapEvent extends YEvent {
 }
 
 /**
- * @template T number|string|Object|Array|ArrayBuffer
+ * @template T number|string|Object|Array|Uint8Array
  * A shared Map implementation.
  *
  * @extends AbstractType<YMapEvent<T>>
@@ -60,19 +60,23 @@ export class YMap extends AbstractType {
    * * This type is sent to other client
    * * Observer functions are fired
    *
-   * @param {Y} y The Yjs instance
-   * @param {ItemType} item
+   * @param {Doc} y The Yjs instance
+   * @param {Item} item
    *
    * @private
    */
   _integrate (y, item) {
     super._integrate(y, item)
-    // @ts-ignore
-    for (let [key, value] of this._prelimContent) {
+    for (let [key, value] of /** @type {Map<string, any>} */ (this._prelimContent)) {
       this.set(key, value)
     }
     this._prelimContent = null
   }
+
+  _copy () {
+    return new YMap()
+  }
+
   /**
    * Creates YMapEvent and calls observers.
    *
@@ -97,7 +101,7 @@ export class YMap extends AbstractType {
     const map = {}
     for (let [key, item] of this._map) {
       if (!item.deleted) {
-        const v = item.getContent()[0]
+        const v = item.content.getContent()[item.length - 1]
         map[key] = v instanceof AbstractType ? v.toJSON() : v
       }
     }
@@ -107,18 +111,46 @@ export class YMap extends AbstractType {
   /**
    * Returns the keys for each element in the YMap Type.
    *
-   * @return {Iterator<string>}
+   * @return {IterableIterator<string>}
    */
   keys () {
-    return iterator.iteratorMap(createMapIterator(this._map), v => v[0])
+    return iterator.iteratorMap(createMapIterator(this._map), /** @param {any} v */ v => v[0])
   }
+
   /**
-   * Returns the value for each element in the YMap Type.
+   * Returns the keys for each element in the YMap Type.
    *
-   * @return {IterableIterator<T>}
+   * @return {IterableIterator<string>}
+   */
+  values () {
+    return iterator.iteratorMap(createMapIterator(this._map), /** @param {any} v */ v => v[1].content.getContent()[v[1].length - 1])
+  }
+
+  /**
+   * Returns an Iterator of [key, value] pairs
+   *
+   * @return {IterableIterator<any>}
    */
   entries () {
-    return iterator.iteratorMap(createMapIterator(this._map), v => v[1].getContent()[0])
+    return iterator.iteratorMap(createMapIterator(this._map), /** @param {any} v */ v => [v[0], v[1].content.getContent()[v[1].length - 1]])
+  }
+
+  /**
+   * Executes a provided function on once on overy key-value pair.
+   *
+   * @param {function(T,string,YMap<T>):void} f A function to execute on every element of this YArray.
+   */
+  forEach (f) {
+    /**
+     * @type {Object<string,T>}
+     */
+    const map = {}
+    for (let [key, item] of this._map) {
+      if (!item.deleted) {
+        f(item.content.getContent()[item.length - 1], key, this)
+      }
+    }
+    return map
   }
 
   /**
@@ -134,13 +166,12 @@ export class YMap extends AbstractType {
    * @param {string} key The key of the element to remove.
    */
   delete (key) {
-    if (this._y !== null) {
-      transact(this._y, transaction => {
+    if (this.doc !== null) {
+      transact(this.doc, transaction => {
         typeMapDelete(transaction, this, key)
       })
     } else {
-      // @ts-ignore
-      this._prelimContent.delete(key)
+      /** @type {Map<string, any>} */ (this._prelimContent).delete(key)
     }
   }
 
@@ -151,13 +182,12 @@ export class YMap extends AbstractType {
    * @param {T} value The value of the element to add
    */
   set (key, value) {
-    if (this._y !== null) {
-      transact(this._y, transaction => {
+    if (this.doc !== null) {
+      transact(this.doc, transaction => {
         typeMapSet(transaction, this, key, value)
       })
     } else {
-      // @ts-ignore
-      this._prelimContent.set(key, value)
+      /** @type {Map<string, any>} */ (this._prelimContent).set(key, value)
     }
     return value
   }
@@ -169,8 +199,7 @@ export class YMap extends AbstractType {
    * @return {T|undefined}
    */
   get (key) {
-    // @ts-ignore
-    return typeMapGet(this, key)
+    return /** @type {any} */ (typeMapGet(this, key))
   }
 
   /**

src/types/YText.js

@@ -5,9 +5,6 @@
 
 import {
   YEvent,
-  ItemEmbed,
-  ItemString,
-  ItemFormat,
   AbstractType,
   nextID,
   createID,
@@ -16,16 +13,28 @@ import {
   YTextRefID,
   callTypeObservers,
   transact,
-  Y, ItemType, AbstractItem, Snapshot, StructStore, Transaction // eslint-disable-line
+  ContentEmbed,
+  ContentFormat,
+  ContentString,
+  splitSnapshotAffectedStructs,
+  ID, Doc, Item, Snapshot, Transaction // eslint-disable-line
 } from '../internals.js'
 
 import * as decoding from 'lib0/decoding.js' // eslint-disable-line
 import * as encoding from 'lib0/encoding.js'
+import * as object from 'lib0/object.js'
+
+/**
+ * @param {any} a
+ * @param {any} b
+ * @return {boolean}
+ */
+const equalAttrs = (a, b) => a === b || (typeof a === 'object' && typeof b === 'object' && a && b && object.equalFlat(a, b))
 
 export class ItemListPosition {
   /**
-   * @param {AbstractItem|null} left
-   * @param {AbstractItem|null} right
+   * @param {Item|null} left
+   * @param {Item|null} right
    */
   constructor (left, right) {
     this.left = left
@@ -35,8 +44,8 @@ export class ItemListPosition {
 
 export class ItemTextListPosition extends ItemListPosition {
   /**
-   * @param {AbstractItem|null} left
-   * @param {AbstractItem|null} right
+   * @param {Item|null} left
+   * @param {Item|null} right
    * @param {Map<string,any>} currentAttributes
    */
   constructor (left, right, currentAttributes) {
@@ -47,8 +56,8 @@ export class ItemTextListPosition extends ItemListPosition {
 
 export class ItemInsertionResult extends ItemListPosition {
   /**
-   * @param {AbstractItem|null} left
-   * @param {AbstractItem|null} right
+   * @param {Item|null} left
+   * @param {Item|null} right
    * @param {Map<string,any>} negatedAttributes
    */
   constructor (left, right, negatedAttributes) {
@@ -59,33 +68,31 @@ export class ItemInsertionResult extends ItemListPosition {
 
 /**
  * @param {Transaction} transaction
- * @param {StructStore} store
  * @param {Map<string,any>} currentAttributes
- * @param {AbstractItem|null} left
- * @param {AbstractItem|null} right
+ * @param {Item|null} left
+ * @param {Item|null} right
  * @param {number} count
  * @return {ItemTextListPosition}
  *
  * @private
  * @function
  */
-const findNextPosition = (transaction, store, currentAttributes, left, right, count) => {
+const findNextPosition = (transaction, currentAttributes, left, right, count) => {
   while (right !== null && count > 0) {
-    switch (right.constructor) {
-      case ItemEmbed:
-      case ItemString:
+    switch (right.content.constructor) {
+      case ContentEmbed:
+      case ContentString:
         if (!right.deleted) {
           if (count < right.length) {
             // split right
-            getItemCleanStart(transaction, store, createID(right.id.client, right.id.clock + count))
+            getItemCleanStart(transaction, createID(right.id.client, right.id.clock + count))
           }
           count -= right.length
         }
         break
-      case ItemFormat:
+      case ContentFormat:
         if (!right.deleted) {
-          // @ts-ignore right is ItemFormat
-          updateCurrentAttributes(currentAttributes, right)
+          updateCurrentAttributes(currentAttributes, /** @type {ContentFormat} */ (right.content))
         }
         break
     }
@@ -97,7 +104,6 @@ const findNextPosition = (transaction, store, currentAttributes, left, right, co
 
 /**
  * @param {Transaction} transaction
- * @param {StructStore} store
  * @param {AbstractType<any>} parent
  * @param {number} index
  * @return {ItemTextListPosition}
@@ -105,11 +111,11 @@ const findNextPosition = (transaction, store, currentAttributes, left, right, co
  * @private
  * @function
  */
-const findPosition = (transaction, store, parent, index) => {
+const findPosition = (transaction, parent, index) => {
   let currentAttributes = new Map()
   let left = null
   let right = parent._start
-  return findNextPosition(transaction, store, currentAttributes, left, right, index)
+  return findNextPosition(transaction, currentAttributes, left, right, index)
 }
 
 /**
@@ -117,8 +123,8 @@ const findPosition = (transaction, store, parent, index) => {
  *
  * @param {Transaction} transaction
  * @param {AbstractType<any>} parent
- * @param {AbstractItem|null} left
- * @param {AbstractItem|null} right
+ * @param {Item|null} left
+ * @param {Item|null} right
  * @param {Map<string,any>} negatedAttributes
  * @return {ItemListPosition}
  *
@@ -130,36 +136,33 @@ const insertNegatedAttributes = (transaction, parent, left, right, negatedAttrib
   while (
     right !== null && (
       right.deleted === true || (
-        right.constructor === ItemFormat &&
-        // @ts-ignore right is ItemFormat
-        (negatedAttributes.get(right.key) === right.value)
+        right.content.constructor === ContentFormat &&
+        equalAttrs(negatedAttributes.get(/** @type {ContentFormat} */ (right.content).key), /** @type {ContentFormat} */ (right.content).value)
       )
     )
   ) {
     if (!right.deleted) {
-      // @ts-ignore right is ItemFormat
-      negatedAttributes.delete(right.key)
+      negatedAttributes.delete(/** @type {ContentFormat} */ (right.content).key)
     }
     left = right
     right = right.right
   }
   for (let [key, val] of negatedAttributes) {
-    left = new ItemFormat(nextID(transaction), left, left === null ? null : left.lastId, right, right === null ? null : right.id, parent, null, key, val)
+    left = new Item(nextID(transaction), left, left === null ? null : left.lastId, right, right === null ? null : right.id, parent, null, new ContentFormat(key, val))
     left.integrate(transaction)
   }
-  return {left, right}
+  return { left, right }
 }
 
 /**
  * @param {Map<string,any>} currentAttributes
- * @param {ItemFormat} item
+ * @param {ContentFormat} format
  *
  * @private
  * @function
  */
-const updateCurrentAttributes = (currentAttributes, item) => {
-  const value = item.value
-  const key = item.key
+const updateCurrentAttributes = (currentAttributes, format) => {
+  const { key, value } = format
   if (value === null) {
     currentAttributes.delete(key)
   } else {
@@ -168,8 +171,8 @@ const updateCurrentAttributes = (currentAttributes, item) => {
 }
 
 /**
- * @param {AbstractItem|null} left
- * @param {AbstractItem|null} right
+ * @param {Item|null} left
+ * @param {Item|null} right
  * @param {Map<string,any>} currentAttributes
  * @param {Object<string,any>} attributes
  * @return {ItemListPosition}
@@ -184,11 +187,9 @@ const minimizeAttributeChanges = (left, right, currentAttributes, attributes) =>
       break
     } else if (right.deleted) {
       // continue
-    // @ts-ignore right is ItemFormat
-    } else if (right.constructor === ItemFormat && (attributes[right.key] || null) === right.value) {
+    } else if (right.content.constructor === ContentFormat && equalAttrs(attributes[(/** @type {ContentFormat} */ (right.content)).key] || null, /** @type {ContentFormat} */ (right.content).value)) {
       // found a format, update currentAttributes and continue
-      // @ts-ignore right is ItemFormat
-      updateCurrentAttributes(currentAttributes, right)
+      updateCurrentAttributes(currentAttributes, /** @type {ContentFormat} */ (right.content))
     } else {
       break
     }
@@ -201,8 +202,8 @@ const minimizeAttributeChanges = (left, right, currentAttributes, attributes) =>
 /**
  * @param {Transaction} transaction
  * @param {AbstractType<any>} parent
- * @param {AbstractItem|null} left
- * @param {AbstractItem|null} right
+ * @param {Item|null} left
+ * @param {Item|null} right
  * @param {Map<string,any>} currentAttributes
  * @param {Object<string,any>} attributes
  * @return {ItemInsertionResult}
@@ -215,11 +216,11 @@ const insertAttributes = (transaction, parent, left, right, currentAttributes, a
   // insert format-start items
   for (let key in attributes) {
     const val = attributes[key]
-    const currentVal = currentAttributes.get(key)
-    if (currentVal !== val) {
+    const currentVal = currentAttributes.get(key) || null
+    if (!equalAttrs(currentVal, val)) {
       // save negated attribute (set null if currentVal undefined)
-      negatedAttributes.set(key, currentVal || null)
-      left = new ItemFormat(nextID(transaction), left, left === null ? null : left.lastId, right, right === null ? null : right.id, parent, null, key, val)
+      negatedAttributes.set(key, currentVal)
+      left = new Item(nextID(transaction), left, left === null ? null : left.lastId, right, right === null ? null : right.id, parent, null, new ContentFormat(key, val))
       left.integrate(transaction)
     }
   }
@@ -229,10 +230,10 @@ const insertAttributes = (transaction, parent, left, right, currentAttributes, a
 /**
  * @param {Transaction} transaction
  * @param {AbstractType<any>} parent
- * @param {AbstractItem|null} left
- * @param {AbstractItem|null} right
+ * @param {Item|null} left
+ * @param {Item|null} right
  * @param {Map<string,any>} currentAttributes
- * @param {string} text
+ * @param {string|object} text
  * @param {Object<string,any>} attributes
  * @return {ItemListPosition}
  *
@@ -250,11 +251,8 @@ const insertText = (transaction, parent, left, right, currentAttributes, text, a
   left = insertPos.left
   right = insertPos.right
   // insert content
-  if (text.constructor === String) {
-    left = new ItemString(nextID(transaction), left, left === null ? null : left.lastId, right, right === null ? null : right.id, parent, null, text)
-  } else {
-    left = new ItemEmbed(nextID(transaction), left, left === null ? null : left.lastId, right, right === null ? null : right.id, parent, null, text)
-  }
+  const content = text.constructor === String ? new ContentString(text) : new ContentEmbed(text)
+  left = new Item(nextID(transaction), left, left === null ? null : left.lastId, right, right === null ? null : right.id, parent, null, content)
   left.integrate(transaction)
   return insertNegatedAttributes(transaction, parent, left, insertPos.right, insertPos.negatedAttributes)
 }
@@ -262,8 +260,8 @@ const insertText = (transaction, parent, left, right, currentAttributes, text, a
 /**
  * @param {Transaction} transaction
  * @param {AbstractType<any>} parent
- * @param {AbstractItem|null} left
- * @param {AbstractItem|null} right
+ * @param {Item|null} left
+ * @param {Item|null} right
  * @param {Map<string,any>} currentAttributes
  * @param {number} length
  * @param {Object<string,any>} attributes
@@ -281,29 +279,25 @@ const formatText = (transaction, parent, left, right, currentAttributes, length,
   // iterate until first non-format or null is found
   // delete all formats with attributes[format.key] != null
   while (length > 0 && right !== null) {
-    if (right.deleted === false) {
-      switch (right.constructor) {
-        case ItemFormat:
-          // @ts-ignore right is ItemFormat
-          const attr = attributes[right.key]
+    if (!right.deleted) {
+      switch (right.content.constructor) {
+        case ContentFormat:
+          const { key, value } = /** @type {ContentFormat} */ (right.content)
+          const attr = attributes[key]
           if (attr !== undefined) {
-            // @ts-ignore right is ItemFormat
-            if (attr === right.value) {
-              // @ts-ignore right is ItemFormat
-              negatedAttributes.delete(right.key)
+            if (equalAttrs(attr, value)) {
+              negatedAttributes.delete(key)
             } else {
-              // @ts-ignore right is ItemFormat
-              negatedAttributes.set(right.key, right.value)
+              negatedAttributes.set(key, value)
             }
             right.delete(transaction)
           }
-          // @ts-ignore right is ItemFormat
-          updateCurrentAttributes(currentAttributes, right)
+          updateCurrentAttributes(currentAttributes, /** @type {ContentFormat} */ (right.content))
           break
-        case ItemEmbed:
-        case ItemString:
+        case ContentEmbed:
+        case ContentString:
           if (length < right.length) {
-            getItemCleanStart(transaction, transaction.y.store, createID(right.id.client, right.id.clock + length))
+            getItemCleanStart(transaction, createID(right.id.client, right.id.clock + length))
           }
           length -= right.length
           break
@@ -312,13 +306,24 @@ const formatText = (transaction, parent, left, right, currentAttributes, length,
     left = right
     right = right.right
   }
+  // Quill just assumes that the editor starts with a newline and that it always
+  // ends with a newline. We only insert that newline when a new newline is
+  // inserted - i.e when length is bigger than type.length
+  if (length > 0) {
+    let newlines = ''
+    for (; length > 0; length--) {
+      newlines += '\n'
+    }
+    left = new Item(nextID(transaction), left, left === null ? null : left.lastId, right, right === null ? null : right.id, parent, null, new ContentString(newlines))
+    left.integrate(transaction)
+  }
   return insertNegatedAttributes(transaction, parent, left, right, negatedAttributes)
 }
 
 /**
  * @param {Transaction} transaction
- * @param {AbstractItem|null} left
- * @param {AbstractItem|null} right
+ * @param {Item|null} left
+ * @param {Item|null} right
  * @param {Map<string,any>} currentAttributes
  * @param {number} length
  * @return {ItemListPosition}
@@ -329,15 +334,14 @@ const formatText = (transaction, parent, left, right, currentAttributes, length,
 const deleteText = (transaction, left, right, currentAttributes, length) => {
   while (length > 0 && right !== null) {
     if (right.deleted === false) {
-      switch (right.constructor) {
-        case ItemFormat:
-          // @ts-ignore right is ItemFormat
-          updateCurrentAttributes(currentAttributes, right)
+      switch (right.content.constructor) {
+        case ContentFormat:
+          updateCurrentAttributes(currentAttributes, /** @type {ContentFormat} */ (right.content))
           break
-        case ItemEmbed:
-        case ItemString:
+        case ContentEmbed:
+        case ContentString:
           if (length < right.length) {
-            getItemCleanStart(transaction, transaction.y.store, createID(right.id.client, right.id.clock + length))
+            getItemCleanStart(transaction, createID(right.id.client, right.id.clock + length))
           }
           length -= right.length
           right.delete(transaction)
@@ -388,7 +392,7 @@ const deleteText = (transaction, left, right, currentAttributes, length) => {
 /**
  * Event that describes the changes on a YText type.
  */
-class YTextEvent extends YEvent {
+export class YTextEvent extends YEvent {
   /**
    * @param {YText} ytext
    * @param {Transaction} transaction
@@ -411,13 +415,10 @@ class YTextEvent extends YEvent {
    */
   get delta () {
     if (this._delta === null) {
-      const y = this.target._y
-      // @ts-ignore
+      const y = /** @type {Doc} */ (this.target.doc)
+      this._delta = []
       transact(y, transaction => {
-        /**
-         * @type {Array<DeltaItem>}
-         */
-        const delta = []
+        const delta = /** @type {Array<DeltaItem>} */ (this._delta)
         const currentAttributes = new Map() // saves all current attributes for insert
         const oldAttributes = new Map()
         let item = this.target._start
@@ -432,7 +433,6 @@ class YTextEvent extends YEvent {
         let insert = ''
         let retain = 0
         let deleteLen = 0
-        this._delta = delta
         const addOp = () => {
           if (action !== null) {
             /**
@@ -472,14 +472,15 @@ class YTextEvent extends YEvent {
           }
         }
         while (item !== null) {
-          switch (item.constructor) {
-            case ItemEmbed:
+          switch (item.content.constructor) {
+            case ContentEmbed:
               if (this.adds(item)) {
-                addOp()
-                action = 'insert'
-                // @ts-ignore item is ItemFormat
-                insert = item.embed
-                addOp()
+                if (!this.deletes(item)) {
+                  addOp()
+                  action = 'insert'
+                  insert = /** @type {ContentEmbed} */ (item.content).embed
+                  addOp()
+                }
               } else if (this.deletes(item)) {
                 if (action !== 'delete') {
                   addOp()
@@ -494,14 +495,15 @@ class YTextEvent extends YEvent {
                 retain += 1
               }
               break
-            case ItemString:
+            case ContentString:
               if (this.adds(item)) {
-                if (action !== 'insert') {
-                  addOp()
-                  action = 'insert'
+                if (!this.deletes(item)) {
+                  if (action !== 'insert') {
+                    addOp()
+                    action = 'insert'
+                  }
+                  insert += /** @type {ContentString} */ (item.content).str
                 }
-                // @ts-ignore
-                insert += item.string
               } else if (this.deletes(item)) {
                 if (action !== 'delete') {
                   addOp()
@@ -516,57 +518,45 @@ class YTextEvent extends YEvent {
                 retain += item.length
               }
               break
-            case ItemFormat:
+            case ContentFormat:
+              const { key, value } = /** @type {ContentFormat} */ (item.content)
               if (this.adds(item)) {
-                // @ts-ignore item is ItemFormat
-                const curVal = currentAttributes.get(item.key) || null
-                // @ts-ignore item is ItemFormat
-                if (curVal !== item.value) {
-                  if (action === 'retain') {
-                    addOp()
-                  }
-                  // @ts-ignore item is ItemFormat
-                  if (item.value === (oldAttributes.get(item.key) || null)) {
-                    // @ts-ignore item is ItemFormat
-                    delete attributes[item.key]
-                  } else {
-                    // @ts-ignore item is ItemFormat
-                    attributes[item.key] = item.value
-                  }
-                } else {
-                  item.delete(transaction)
-                }
-              } else if (this.deletes(item)) {
-                // @ts-ignore item is ItemFormat
-                oldAttributes.set(item.key, item.value)
-                // @ts-ignore item is ItemFormat
-                const curVal = currentAttributes.get(item.key) || null
-                // @ts-ignore item is ItemFormat
-                if (curVal !== item.value) {
-                  if (action === 'retain') {
-                    addOp()
-                  }
-                  // @ts-ignore item is ItemFormat
-                  attributes[item.key] = curVal
-                }
-              } else if (!item.deleted) {
-                // @ts-ignore item is ItemFormat
-                oldAttributes.set(item.key, item.value)
-                // @ts-ignore item is ItemFormat
-                const attr = attributes[item.key]
-                if (attr !== undefined) {
-                  // @ts-ignore item is ItemFormat
-                  if (attr !== item.value) {
+                if (!this.deletes(item)) {
+                  const curVal = currentAttributes.get(key) || null
+                  if (!equalAttrs(curVal, value)) {
                     if (action === 'retain') {
                       addOp()
                     }
-                    // @ts-ignore item is ItemFormat
-                    if (item.value === null) {
-                      // @ts-ignore item is ItemFormat
-                      attributes[item.key] = item.value
+                    if (equalAttrs(value, (oldAttributes.get(key) || null))) {
+                      delete attributes[key]
                     } else {
-                      // @ts-ignore item is ItemFormat
-                      delete attributes[item.key]
+                      attributes[key] = value
+                    }
+                  } else {
+                    item.delete(transaction)
+                  }
+                }
+              } else if (this.deletes(item)) {
+                oldAttributes.set(key, value)
+                const curVal = currentAttributes.get(key) || null
+                if (!equalAttrs(curVal, value)) {
+                  if (action === 'retain') {
+                    addOp()
+                  }
+                  attributes[key] = curVal
+                }
+              } else if (!item.deleted) {
+                oldAttributes.set(key, value)
+                const attr = attributes[key]
+                if (attr !== undefined) {
+                  if (!equalAttrs(attr, value)) {
+                    if (action === 'retain') {
+                      addOp()
+                    }
+                    if (value === null) {
+                      attributes[key] = value
+                    } else {
+                      delete attributes[key]
                     }
                   } else {
                     item.delete(transaction)
@@ -577,26 +567,24 @@ class YTextEvent extends YEvent {
                 if (action === 'insert') {
                   addOp()
                 }
-                // @ts-ignore item is ItemFormat
-                updateCurrentAttributes(currentAttributes, item)
+                updateCurrentAttributes(currentAttributes, /** @type {ContentFormat} */ (item.content))
               }
               break
           }
           item = item.right
         }
         addOp()
-        while (this._delta.length > 0) {
-          let lastOp = this._delta[this._delta.length - 1]
+        while (delta.length > 0) {
+          let lastOp = delta[delta.length - 1]
           if (lastOp.retain !== undefined && lastOp.attributes === undefined) {
             // retain delta's if they don't assign attributes
-            this._delta.pop()
+            delta.pop()
           } else {
             break
           }
         }
       })
     }
-    // @ts-ignore _delta is defined above
     return this._delta
   }
 }
@@ -617,10 +605,11 @@ export class YText extends AbstractType {
   constructor (string) {
     super()
     /**
-     * @type {Array<string>?}
+     * Array of pending operations on this type
+     * @type {Array<function():void>?}
      * @private
      */
-    this._prelimContent = string !== undefined ? [string] : []
+    this._pending = string !== undefined ? [() => this.insert(0, string)] : []
   }
 
   get length () {
@@ -628,16 +617,23 @@ export class YText extends AbstractType {
   }
 
   /**
-   * @param {Y} y
-   * @param {ItemType} item
+   * @param {Doc} y
+   * @param {Item} item
    *
    * @private
    */
   _integrate (y, item) {
     super._integrate(y, item)
-    // @ts-ignore this._prelimContent is still defined
-    this.insert(0, this._prelimContent.join(''))
-    this._prelimContent = null
+    try {
+      /** @type {Array<function>} */ (this._pending).forEach(f => f())
+    } catch (e) {
+      console.error(e)
+    }
+    this._pending = null
+  }
+
+  _copy () {
+    return new YText()
   }
 
   /**
@@ -652,10 +648,6 @@ export class YText extends AbstractType {
     callTypeObservers(this, transaction, new YTextEvent(this, transaction))
   }
 
-  toDom () {
-    return document.createTextNode(this.toString())
-  }
-
   /**
    * Returns the unformatted string representation of this YText type.
    *
@@ -664,53 +656,18 @@ export class YText extends AbstractType {
   toString () {
     let str = ''
     /**
-     * @type {AbstractItem|null}
+     * @type {Item|null}
      */
     let n = this._start
     while (n !== null) {
-      if (!n.deleted && n.countable && n.constructor === ItemString) {
-        // @ts-ignore
-        str += n.string
+      if (!n.deleted && n.countable && n.content.constructor === ContentString) {
+        str += /** @type {ContentString} */ (n.content).str
       }
       n = n.right
     }
     return str
   }
 
-  toDomString () {
-    // @ts-ignore
-    return this.toDelta().map(delta => {
-      const nestedNodes = []
-      for (let nodeName in delta.attributes) {
-        const attrs = []
-        for (let key in delta.attributes[nodeName]) {
-          attrs.push({ key, value: delta.attributes[nodeName][key] })
-        }
-        // sort attributes to get a unique order
-        attrs.sort((a, b) => a.key < b.key ? -1 : 1)
-        nestedNodes.push({ nodeName, attrs })
-      }
-      // sort node order to get a unique order
-      nestedNodes.sort((a, b) => a.nodeName < b.nodeName ? -1 : 1)
-      // now convert to dom string
-      let str = ''
-      for (let i = 0; i < nestedNodes.length; i++) {
-        const node = nestedNodes[i]
-        str += `<${node.nodeName}`
-        for (let j = 0; j < node.attrs.length; j++) {
-          const attr = node.attrs[i]
-          str += ` ${attr.key}="${attr.value}"`
-        }
-        str += '>'
-      }
-      str += delta.insert
-      for (let i = nestedNodes.length - 1; i >= 0; i--) {
-        str += `</${nestedNodes[i].nodeName}>`
-      }
-      return str
-    })
-  }
-
   /**
    * Apply a {@link Delta} on this shared YText type.
    *
@@ -719,8 +676,8 @@ export class YText extends AbstractType {
    * @public
    */
   applyDelta (delta) {
-    if (this._y !== null) {
-      transact(this._y, transaction => {
+    if (this.doc !== null) {
+      transact(this.doc, transaction => {
         /**
          * @type {ItemListPosition}
          */
@@ -729,7 +686,15 @@ export class YText extends AbstractType {
         for (let i = 0; i < delta.length; i++) {
           const op = delta[i]
           if (op.insert !== undefined) {
-            pos = insertText(transaction, this, pos.left, pos.right, currentAttributes, op.insert, op.attributes || {})
+            // Quill assumes that the content starts with an empty paragraph.
+            // Yjs/Y.Text assumes that it starts empty. We always hide that
+            // there is a newline at the end of the content.
+            // If we omit this step, clients will see a different number of
+            // paragraphs, but nothing bad will happen.
+            const ins = (typeof op.insert === 'string' && i === delta.length - 1 && pos.right === null && op.insert.slice(-1) === '\n') ? op.insert.slice(0, -1) : op.insert
+            if (typeof ins !== 'string' || ins.length > 0) {
+              pos = insertText(transaction, this, pos.left, pos.right, currentAttributes, ins, op.attributes || {})
+            }
           } else if (op.retain !== undefined) {
             pos = formatText(transaction, this, pos.left, pos.right, currentAttributes, op.retain, op.attributes || {})
           } else if (op.delete !== undefined) {
@@ -737,6 +702,8 @@ export class YText extends AbstractType {
           }
         }
       })
+    } else {
+      /** @type {Array<function>} */ (this._pending).push(() => this.applyDelta(delta))
     }
   }
 
@@ -745,21 +712,19 @@ export class YText extends AbstractType {
    *
    * @param {Snapshot} [snapshot]
    * @param {Snapshot} [prevSnapshot]
+   * @param {function('removed' | 'added', ID):any} [computeYChange]
    * @return {any} The Delta representation of this type.
    *
    * @public
    */
-  toDelta (snapshot, prevSnapshot) {
+  toDelta (snapshot, prevSnapshot, computeYChange) {
     /**
      * @type{Array<any>}
      */
     const ops = []
     const currentAttributes = new Map()
+    const doc = /** @type {Doc} */ (this.doc)
     let str = ''
-    /**
-     * @type {AbstractItem|null}
-     */
-    // @ts-ignore
     let n = this._start
     function packStr () {
       if (str.length > 0) {
@@ -784,38 +749,54 @@ export class YText extends AbstractType {
         str = ''
       }
     }
-    while (n !== null) {
-      if (isVisible(n, snapshot) || (prevSnapshot !== undefined && isVisible(n, prevSnapshot))) {
-        switch (n.constructor) {
-          case ItemString:
-            const cur = currentAttributes.get('ychange')
-            if (snapshot !== undefined && !isVisible(n, snapshot)) {
-              if (cur === undefined || cur.user !== n.id.client || cur.state !== 'removed') {
-                packStr()
-                currentAttributes.set('ychange', { user: n.id.client, state: 'removed' })
-              }
-            } else if (prevSnapshot !== undefined && !isVisible(n, prevSnapshot)) {
-              if (cur === undefined || cur.user !== n.id.client || cur.state !== 'added') {
-                packStr()
-                currentAttributes.set('ychange', { user: n.id.client, state: 'added' })
-              }
-            } else if (cur !== undefined) {
-              packStr()
-              currentAttributes.delete('ychange')
-            }
-            // @ts-ignore
-            str += n.string
-            break
-          case ItemFormat:
-            packStr()
-            // @ts-ignore
-            updateCurrentAttributes(currentAttributes, n)
-            break
-        }
+    // snapshots are merged again after the transaction, so we need to keep the
+    // transalive until we are done
+    transact(doc, transaction => {
+      if (snapshot) {
+        splitSnapshotAffectedStructs(transaction, snapshot)
       }
-      n = n.right
-    }
-    packStr()
+      if (prevSnapshot) {
+        splitSnapshotAffectedStructs(transaction, prevSnapshot)
+      }
+      while (n !== null) {
+        if (isVisible(n, snapshot) || (prevSnapshot !== undefined && isVisible(n, prevSnapshot))) {
+          switch (n.content.constructor) {
+            case ContentString:
+              const cur = currentAttributes.get('ychange')
+              if (snapshot !== undefined && !isVisible(n, snapshot)) {
+                if (cur === undefined || cur.user !== n.id.client || cur.state !== 'removed') {
+                  packStr()
+                  currentAttributes.set('ychange', computeYChange ? computeYChange('removed', n.id) : { type: 'removed' })
+                }
+              } else if (prevSnapshot !== undefined && !isVisible(n, prevSnapshot)) {
+                if (cur === undefined || cur.user !== n.id.client || cur.state !== 'added') {
+                  packStr()
+                  currentAttributes.set('ychange', computeYChange ? computeYChange('added', n.id) : { type: 'added' })
+                }
+              } else if (cur !== undefined) {
+                packStr()
+                currentAttributes.delete('ychange')
+              }
+              str += /** @type {ContentString} */ (n.content).str
+              break
+            case ContentEmbed:
+              packStr()
+              ops.push({
+                insert: /** @type {ContentEmbed} */ (n.content).embed
+              })
+              break
+            case ContentFormat:
+              if (isVisible(n, snapshot)) {
+                packStr()
+                updateCurrentAttributes(currentAttributes, /** @type {ContentFormat} */ (n.content))
+              }
+              break
+          }
+        }
+        n = n.right
+      }
+      packStr()
+    }, splitSnapshotAffectedStructs)
     return ops
   }
 
@@ -824,21 +805,27 @@ export class YText extends AbstractType {
    *
    * @param {number} index The index at which to start inserting.
    * @param {String} text The text to insert at the specified position.
-   * @param {TextAttributes} attributes Optionally define some formatting
+   * @param {TextAttributes} [attributes] Optionally define some formatting
    *                                    information to apply on the inserted
    *                                    Text.
    * @public
    */
-  insert (index, text, attributes = {}) {
+  insert (index, text, attributes) {
     if (text.length <= 0) {
       return
     }
-    const y = this._y
+    const y = this.doc
     if (y !== null) {
       transact(y, transaction => {
-        const {left, right, currentAttributes} = findPosition(transaction, y.store, this, index)
+        const { left, right, currentAttributes } = findPosition(transaction, this, index)
+        if (!attributes) {
+          attributes = {}
+          currentAttributes.forEach((v, k) => { attributes[k] = v })
+        }
         insertText(transaction, this, left, right, currentAttributes, text, attributes)
       })
+    } else {
+      /** @type {Array<function>} */ (this._pending).push(() => this.insert(index, text, attributes))
     }
   }
 
@@ -856,12 +843,14 @@ export class YText extends AbstractType {
     if (embed.constructor !== Object) {
       throw new Error('Embed must be an Object')
     }
-    const y = this._y
+    const y = this.doc
     if (y !== null) {
       transact(y, transaction => {
-        const { left, right, currentAttributes } = findPosition(transaction, y.store, this, index)
+        const { left, right, currentAttributes } = findPosition(transaction, this, index)
         insertText(transaction, this, left, right, currentAttributes, embed, attributes)
       })
+    } else {
+      /** @type {Array<function>} */ (this._pending).push(() => this.insertEmbed(index, embed, attributes))
     }
   }
 
@@ -877,12 +866,14 @@ export class YText extends AbstractType {
     if (length === 0) {
       return
     }
-    const y = this._y
+    const y = this.doc
     if (y !== null) {
       transact(y, transaction => {
-        const { left, right, currentAttributes } = findPosition(transaction, y.store, this, index)
+        const { left, right, currentAttributes } = findPosition(transaction, this, index)
         deleteText(transaction, left, right, currentAttributes, length)
       })
+    } else {
+      /** @type {Array<function>} */ (this._pending).push(() => this.delete(index, length))
     }
   }
 
@@ -897,15 +888,17 @@ export class YText extends AbstractType {
    * @public
    */
   format (index, length, attributes) {
-    const y = this._y
+    const y = this.doc
     if (y !== null) {
       transact(y, transaction => {
-        let { left, right, currentAttributes } = findPosition(transaction, y.store, this, index)
+        let { left, right, currentAttributes } = findPosition(transaction, this, index)
         if (right === null) {
           return
         }
         formatText(transaction, this, left, right, currentAttributes, length, attributes)
       })
+    } else {
+      /** @type {Array<function>} */ (this._pending).push(() => this.format(index, length, attributes))
     }
   }
 

src/types/YXmlElement.js

@@ -1,244 +1,19 @@
-/**
- * @module YXml
- */
 
 import {
-  YXmlEvent,
-  AbstractType,
-  typeArrayMap,
-  typeArrayForEach,
+  YXmlFragment,
+  transact,
+  typeMapDelete,
+  typeMapSet,
   typeMapGet,
   typeMapGetAll,
-  typeArrayInsertGenerics,
-  typeArrayDelete,
-  typeMapSet,
-  typeMapDelete,
+  typeListForEach,
   YXmlElementRefID,
-  callTypeObservers,
-  transact,
-  Y, Transaction, ItemType, YXmlText, YXmlHook, Snapshot // eslint-disable-line
+  Snapshot, Doc, Item // eslint-disable-line
 } from '../internals.js'
 
 import * as encoding from 'lib0/encoding.js'
 import * as decoding from 'lib0/decoding.js'
 
-/**
- * Define the elements to which a set of CSS queries apply.
- * {@link https://developer.mozilla.org/en-US/docs/Web/CSS/CSS_Selectors|CSS_Selectors}
- *
- * @example
- *   query = '.classSelector'
- *   query = 'nodeSelector'
- *   query = '#idSelector'
- *
- * @typedef {string} CSS_Selector
- */
-
-/**
- * Dom filter function.
- *
- * @callback domFilter
- * @param {string} nodeName The nodeName of the element
- * @param {Map} attributes The map of attributes.
- * @return {boolean} Whether to include the Dom node in the YXmlElement.
- */
-
-/**
- * Represents a subset of the nodes of a YXmlElement / YXmlFragment and a
- * position within them.
- *
- * Can be created with {@link YXmlFragment#createTreeWalker}
- *
- * @public
- * @implements {IterableIterator}
- */
-export class YXmlTreeWalker {
-  /**
-   * @param {YXmlFragment | YXmlElement} root
-   * @param {function(AbstractType<any>):boolean} [f]
-   */
-  constructor (root, f = () => true) {
-    this._filter = f
-    this._root = root
-    /**
-     * @type {ItemType | null}
-     */
-    // @ts-ignore
-    this._currentNode = root._start
-    this._firstCall = true
-  }
-
-  [Symbol.iterator] () {
-    return this
-  }
-  /**
-   * Get the next node.
-   *
-   * @return {IteratorResult<YXmlElement|YXmlText|YXmlHook>} The next node.
-   *
-   * @public
-   */
-  next () {
-    let n = this._currentNode
-    if (n !== null && (!this._firstCall || n.deleted || !this._filter(n.type))) { // if first call, we check if we can use the first item
-      do {
-        if (!n.deleted && (n.type.constructor === YXmlElement || n.type.constructor === YXmlFragment) && n.type._start !== null) {
-          // walk down in the tree
-          // @ts-ignore
-          n = n.type._start
-        } else {
-          // walk right or up in the tree
-          while (n !== null) {
-            if (n.right !== null) {
-              // @ts-ignore
-              n = n.right
-              break
-            } else if (n.parent === this._root) {
-              n = null
-            } else {
-              n = n.parent._item
-            }
-          }
-        }
-      } while (n !== null && (n.deleted || !this._filter(n.type)))
-    }
-    this._firstCall = false
-    this._currentNode = n
-    if (n === null) {
-      // @ts-ignore return undefined if done=true (the expected result)
-      return { value: undefined, done: true }
-    }
-    // @ts-ignore
-    return { value: n.type, done: false }
-  }
-}
-
-/**
- * Represents a list of {@link YXmlElement}.and {@link YXmlText} types.
- * A YxmlFragment is similar to a {@link YXmlElement}, but it does not have a
- * nodeName and it does not have attributes. Though it can be bound to a DOM
- * element - in this case the attributes and the nodeName are not shared.
- *
- * @public
- * @extends AbstractType<YXmlEvent>
- */
-export class YXmlFragment extends AbstractType {
-  /**
-   * Create a subtree of childNodes.
-   *
-   * @example
-   * const walker = elem.createTreeWalker(dom => dom.nodeName === 'div')
-   * for (let node in walker) {
-   *   // `node` is a div node
-   *   nop(node)
-   * }
-   *
-   * @param {function(AbstractType<any>):boolean} filter Function that is called on each child element and
-   *                          returns a Boolean indicating whether the child
-   *                          is to be included in the subtree.
-   * @return {YXmlTreeWalker} A subtree and a position within it.
-   *
-   * @public
-   */
-  createTreeWalker (filter) {
-    return new YXmlTreeWalker(this, filter)
-  }
-
-  /**
-   * Returns the first YXmlElement that matches the query.
-   * Similar to DOM's {@link querySelector}.
-   *
-   * Query support:
-   *   - tagname
-   * TODO:
-   *   - id
-   *   - attribute
-   *
-   * @param {CSS_Selector} query The query on the children.
-   * @return {YXmlElement|YXmlText|YXmlHook|null} The first element that matches the query or null.
-   *
-   * @public
-   */
-  querySelector (query) {
-    query = query.toUpperCase()
-    // @ts-ignore
-    const iterator = new YXmlTreeWalker(this, element => element.nodeName === query)
-    const next = iterator.next()
-    if (next.done) {
-      return null
-    } else {
-      return next.value
-    }
-  }
-
-  /**
-   * Returns all YXmlElements that match the query.
-   * Similar to Dom's {@link querySelectorAll}.
-   *
-   * @todo Does not yet support all queries. Currently only query by tagName.
-   *
-   * @param {CSS_Selector} query The query on the children
-   * @return {Array<YXmlElement|YXmlText|YXmlHook|null>} The elements that match this query.
-   *
-   * @public
-   */
-  querySelectorAll (query) {
-    query = query.toUpperCase()
-    // @ts-ignore
-    return Array.from(new YXmlTreeWalker(this, element => element.nodeName === query))
-  }
-
-  /**
-   * Creates YXmlEvent and calls observers.
-   * @private
-   *
-   * @param {Transaction} transaction
-   * @param {Set<null|string>} parentSubs Keys changed on this type. `null` if list was modified.
-   */
-  _callObserver (transaction, parentSubs) {
-    callTypeObservers(this, transaction, new YXmlEvent(this, parentSubs, transaction))
-  }
-
-  toString () {
-    return this.toDomString()
-  }
-
-  /**
-   * Get the string representation of all the children of this YXmlFragment.
-   *
-   * @return {string} The string representation of all children.
-   */
-  toDomString () {
-    return typeArrayMap(this, xml => xml.toDomString()).join('')
-  }
-
-  /**
-   * Creates a Dom Element that mirrors this YXmlElement.
-   *
-   * @param {Document} [_document=document] The document object (you must define
-   *                                        this when calling this method in
-   *                                        nodejs)
-   * @param {Object<string, any>} [hooks={}] Optional property to customize how hooks
-   *                                             are presented in the DOM
-   * @param {any} [binding] You should not set this property. This is
-   *                               used if DomBinding wants to create a
-   *                               association to the created DOM type.
-   * @return {Node} The {@link https://developer.mozilla.org/en-US/docs/Web/API/Element|Dom Element}
-   *
-   * @public
-   */
-  toDom (_document = document, hooks = {}, binding) {
-    const fragment = _document.createDocumentFragment()
-    if (binding !== undefined) {
-      binding._createAssociation(fragment, this)
-    }
-    typeArrayForEach(this, xmlType => {
-      fragment.insertBefore(xmlType.toDom(_document, hooks, binding), null)
-    })
-    return fragment
-  }
-}
-
 /**
  * An YXmlElement imitates the behavior of a
  * {@link https://developer.mozilla.org/en-US/docs/Web/API/Element|Dom Element}.
@@ -249,12 +24,7 @@ export class YXmlFragment extends AbstractType {
 export class YXmlElement extends YXmlFragment {
   constructor (nodeName = 'UNDEFINED') {
     super()
-    this.nodeName = nodeName.toUpperCase()
-    /**
-     * @type {Array<any>|null}
-     * @private
-     */
-    this._prelimContent = []
+    this.nodeName = nodeName
     /**
      * @type {Map<string, any>|null}
      * @private
@@ -269,20 +39,16 @@ export class YXmlElement extends YXmlFragment {
    * * This type is sent to other client
    * * Observer functions are fired
    *
-   * @param {Y} y The Yjs instance
-   * @param {ItemType} item
+   * @param {Doc} y The Yjs instance
+   * @param {Item} item
    * @private
    */
   _integrate (y, item) {
     super._integrate(y, item)
-    // @ts-ignore
-    this.insert(0, this._prelimContent)
-    this._prelimContent = null
-    // @ts-ignore
-    this._prelimAttrs.forEach((value, key) => {
+    ;(/** @type {Map<string, any>} */ (this._prelimAttrs)).forEach((value, key) => {
       this.setAttribute(key, value)
     })
-    this._prelimContent = null
+    this._prelimAttrs = null
   }
 
   /**
@@ -295,20 +61,16 @@ export class YXmlElement extends YXmlFragment {
     return new YXmlElement(this.nodeName)
   }
 
-  toString () {
-    return this.toDomString()
-  }
-
   /**
-   * Returns the string representation of this YXmlElement.
+   * Returns the XML serialization of this YXmlElement.
    * The attributes are ordered by attribute-name, so you can easily use this
    * method to compare YXmlElements
    *
-   * @return {String} The string representation of this type.
+   * @return {string} The string representation of this type.
    *
    * @public
    */
-  toDomString () {
+  toString () {
     const attrs = this.getAttributes()
     const stringBuilder = []
     const keys = []
@@ -323,7 +85,7 @@ export class YXmlElement extends YXmlFragment {
     }
     const nodeName = this.nodeName.toLocaleLowerCase()
     const attrsString = stringBuilder.length > 0 ? ' ' + stringBuilder.join(' ') : ''
-    return `<${nodeName}${attrsString}>${super.toDomString()}</${nodeName}>`
+    return `<${nodeName}${attrsString}>${super.toString()}</${nodeName}>`
   }
 
   /**
@@ -334,13 +96,12 @@ export class YXmlElement extends YXmlFragment {
    * @public
    */
   removeAttribute (attributeName) {
-    if (this._y !== null) {
-      transact(this._y, transaction => {
+    if (this.doc !== null) {
+      transact(this.doc, transaction => {
         typeMapDelete(transaction, this, attributeName)
       })
     } else {
-      // @ts-ignore
-      this._prelimAttrs.delete(attributeName)
+      /** @type {Map<string,any>} */ (this._prelimAttrs).delete(attributeName)
     }
   }
 
@@ -353,13 +114,12 @@ export class YXmlElement extends YXmlFragment {
    * @public
    */
   setAttribute (attributeName, attributeValue) {
-    if (this._y !== null) {
-      transact(this._y, transaction => {
+    if (this.doc !== null) {
+      transact(this.doc, transaction => {
         typeMapSet(transaction, this, attributeName, attributeValue)
       })
     } else {
-      // @ts-ignore
-      this._prelimAttrs.set(attributeName, attributeValue)
+      /** @type {Map<string, any>} */ (this._prelimAttrs).set(attributeName, attributeValue)
     }
   }
 
@@ -373,8 +133,7 @@ export class YXmlElement extends YXmlFragment {
    * @public
    */
   getAttribute (attributeName) {
-    // @ts-ignore
-    return typeMapGet(this, attributeName)
+    return /** @type {any} */ (typeMapGet(this, attributeName))
   }
 
   /**
@@ -389,44 +148,6 @@ export class YXmlElement extends YXmlFragment {
     return typeMapGetAll(this)
   }
 
-  /**
-   * Inserts new content at an index.
-   *
-   * @example
-   *  // Insert character 'a' at position 0
-   *  xml.insert(0, [new Y.XmlText('text')])
-   *
-   * @param {number} index The index to insert content at
-   * @param {Array<YXmlElement|YXmlText>} content The array of content
-   */
-  insert (index, content) {
-    if (this._y !== null) {
-      transact(this._y, transaction => {
-        typeArrayInsertGenerics(transaction, this, index, content)
-      })
-    } else {
-      // @ts-ignore _prelimContent is defined because this is not yet integrated
-      this._prelimContent.splice(index, 0, ...content)
-    }
-  }
-
-  /**
-   * Deletes elements starting from an index.
-   *
-   * @param {number} index Index at which to start deleting elements
-   * @param {number} [length=1] The number of elements to remove. Defaults to 1.
-   */
-  delete (index, length = 1) {
-    if (this._y !== null) {
-      transact(this._y, transaction => {
-        typeArrayDelete(transaction, this, index, length)
-      })
-    } else {
-      // @ts-ignore _prelimContent is defined because this is not yet integrated
-      this._prelimContent.splice(index, length)
-    }
-  }
-
   /**
    * Creates a Dom Element that mirrors this YXmlElement.
    *
@@ -442,14 +163,14 @@ export class YXmlElement extends YXmlFragment {
    *
    * @public
    */
-  toDom (_document = document, hooks = {}, binding) {
+  toDOM (_document = document, hooks = {}, binding) {
     const dom = _document.createElement(this.nodeName)
     let attrs = this.getAttributes()
     for (let key in attrs) {
       dom.setAttribute(key, attrs[key])
     }
-    typeArrayForEach(this, yxml => {
-      dom.appendChild(yxml.toDom(_document, hooks, binding))
+    typeListForEach(this, yxml => {
+      dom.appendChild(yxml.toDOM(_document, hooks, binding))
     })
     if (binding !== undefined) {
       binding._createAssociation(dom, this)
@@ -480,11 +201,3 @@ export class YXmlElement extends YXmlFragment {
  * @function
  */
 export const readYXmlElement = decoder => new YXmlElement(decoding.readVarString(decoder))
-/**
- * @param {decoding.Decoder} decoder
- * @return {YXmlFragment}
- *
- * @private
- * @function
- */
-export const readYXmlFragment = decoder => new YXmlFragment()

src/types/YXmlFragment.js

@@ -0,0 +1,339 @@
+/**
+ * @module YXml
+ */
+
+import {
+  YXmlEvent,
+  YXmlElement,
+  AbstractType,
+  typeListMap,
+  typeListForEach,
+  typeListInsertGenerics,
+  typeListDelete,
+  typeListToArray,
+  YXmlFragmentRefID,
+  callTypeObservers,
+  transact,
+  Doc, ContentType, Transaction, Item, YXmlText, YXmlHook, Snapshot // eslint-disable-line
+} from '../internals.js'
+
+import * as encoding from 'lib0/encoding.js'
+import * as decoding from 'lib0/decoding.js' // eslint-disable-line
+
+/**
+ * Define the elements to which a set of CSS queries apply.
+ * {@link https://developer.mozilla.org/en-US/docs/Web/CSS/CSS_Selectors|CSS_Selectors}
+ *
+ * @example
+ *   query = '.classSelector'
+ *   query = 'nodeSelector'
+ *   query = '#idSelector'
+ *
+ * @typedef {string} CSS_Selector
+ */
+
+/**
+ * Dom filter function.
+ *
+ * @callback domFilter
+ * @param {string} nodeName The nodeName of the element
+ * @param {Map} attributes The map of attributes.
+ * @return {boolean} Whether to include the Dom node in the YXmlElement.
+ */
+
+/**
+ * Represents a subset of the nodes of a YXmlElement / YXmlFragment and a
+ * position within them.
+ *
+ * Can be created with {@link YXmlFragment#createTreeWalker}
+ *
+ * @public
+ * @implements {IterableIterator}
+ */
+export class YXmlTreeWalker {
+  /**
+   * @param {YXmlFragment | YXmlElement} root
+   * @param {function(AbstractType<any>):boolean} [f]
+   */
+  constructor (root, f = () => true) {
+    this._filter = f
+    this._root = root
+    /**
+     * @type {Item}
+     */
+    this._currentNode = /** @type {Item} */ (root._start)
+    this._firstCall = true
+  }
+
+  [Symbol.iterator] () {
+    return this
+  }
+  /**
+   * Get the next node.
+   *
+   * @return {IteratorResult<YXmlElement|YXmlText|YXmlHook>} The next node.
+   *
+   * @public
+   */
+  next () {
+    /**
+     * @type {Item|null}
+     */
+    let n = this._currentNode
+    let type = /** @type {ContentType} */ (n.content).type
+    if (n !== null && (!this._firstCall || n.deleted || !this._filter(type))) { // if first call, we check if we can use the first item
+      do {
+        type = /** @type {ContentType} */ (n.content).type
+        if (!n.deleted && (type.constructor === YXmlElement || type.constructor === YXmlFragment) && type._start !== null) {
+          // walk down in the tree
+          n = type._start
+        } else {
+          // walk right or up in the tree
+          while (n !== null) {
+            if (n.right !== null) {
+              n = n.right
+              break
+            } else if (n.parent === this._root) {
+              n = null
+            } else {
+              n = n.parent._item
+            }
+          }
+        }
+      } while (n !== null && (n.deleted || !this._filter(/** @type {ContentType} */ (n.content).type)))
+    }
+    this._firstCall = false
+    if (n === null) {
+      // @ts-ignore
+      return { value: undefined, done: true }
+    }
+    this._currentNode = n
+    return { value: /** @type {any} */ (n.content).type, done: false }
+  }
+}
+
+/**
+ * Represents a list of {@link YXmlElement}.and {@link YXmlText} types.
+ * A YxmlFragment is similar to a {@link YXmlElement}, but it does not have a
+ * nodeName and it does not have attributes. Though it can be bound to a DOM
+ * element - in this case the attributes and the nodeName are not shared.
+ *
+ * @public
+ * @extends AbstractType<YXmlEvent>
+ */
+export class YXmlFragment extends AbstractType {
+  constructor () {
+    super()
+    /**
+     * @type {Array<any>|null}
+     * @private
+     */
+    this._prelimContent = []
+  }
+  /**
+   * Integrate this type into the Yjs instance.
+   *
+   * * Save this struct in the os
+   * * This type is sent to other client
+   * * Observer functions are fired
+   *
+   * @param {Doc} y The Yjs instance
+   * @param {Item} item
+   * @private
+   */
+  _integrate (y, item) {
+    super._integrate(y, item)
+    this.insert(0, /** @type {Array} */ (this._prelimContent))
+    this._prelimContent = null
+  }
+
+  _copy () {
+    return new YXmlFragment()
+  }
+
+  get length () {
+    return this._prelimContent === null ? this._length : this._prelimContent.length
+  }
+
+  /**
+   * Create a subtree of childNodes.
+   *
+   * @example
+   * const walker = elem.createTreeWalker(dom => dom.nodeName === 'div')
+   * for (let node in walker) {
+   *   // `node` is a div node
+   *   nop(node)
+   * }
+   *
+   * @param {function(AbstractType<any>):boolean} filter Function that is called on each child element and
+   *                          returns a Boolean indicating whether the child
+   *                          is to be included in the subtree.
+   * @return {YXmlTreeWalker} A subtree and a position within it.
+   *
+   * @public
+   */
+  createTreeWalker (filter) {
+    return new YXmlTreeWalker(this, filter)
+  }
+
+  /**
+   * Returns the first YXmlElement that matches the query.
+   * Similar to DOM's {@link querySelector}.
+   *
+   * Query support:
+   *   - tagname
+   * TODO:
+   *   - id
+   *   - attribute
+   *
+   * @param {CSS_Selector} query The query on the children.
+   * @return {YXmlElement|YXmlText|YXmlHook|null} The first element that matches the query or null.
+   *
+   * @public
+   */
+  querySelector (query) {
+    query = query.toUpperCase()
+    // @ts-ignore
+    const iterator = new YXmlTreeWalker(this, element => element.nodeName && element.nodeName.toUpperCase() === query)
+    const next = iterator.next()
+    if (next.done) {
+      return null
+    } else {
+      return next.value
+    }
+  }
+
+  /**
+   * Returns all YXmlElements that match the query.
+   * Similar to Dom's {@link querySelectorAll}.
+   *
+   * @todo Does not yet support all queries. Currently only query by tagName.
+   *
+   * @param {CSS_Selector} query The query on the children
+   * @return {Array<YXmlElement|YXmlText|YXmlHook|null>} The elements that match this query.
+   *
+   * @public
+   */
+  querySelectorAll (query) {
+    query = query.toUpperCase()
+    // @ts-ignore
+    return Array.from(new YXmlTreeWalker(this, element => element.nodeName && element.nodeName.toUpperCase() === query))
+  }
+
+  /**
+   * Creates YXmlEvent and calls observers.
+   * @private
+   *
+   * @param {Transaction} transaction
+   * @param {Set<null|string>} parentSubs Keys changed on this type. `null` if list was modified.
+   */
+  _callObserver (transaction, parentSubs) {
+    callTypeObservers(this, transaction, new YXmlEvent(this, parentSubs, transaction))
+  }
+
+  /**
+   * Get the string representation of all the children of this YXmlFragment.
+   *
+   * @return {string} The string representation of all children.
+   */
+  toString () {
+    return typeListMap(this, xml => xml.toString()).join('')
+  }
+
+  toJSON () {
+    return this.toString()
+  }
+
+  /**
+   * Creates a Dom Element that mirrors this YXmlElement.
+   *
+   * @param {Document} [_document=document] The document object (you must define
+   *                                        this when calling this method in
+   *                                        nodejs)
+   * @param {Object<string, any>} [hooks={}] Optional property to customize how hooks
+   *                                             are presented in the DOM
+   * @param {any} [binding] You should not set this property. This is
+   *                               used if DomBinding wants to create a
+   *                               association to the created DOM type.
+   * @return {Node} The {@link https://developer.mozilla.org/en-US/docs/Web/API/Element|Dom Element}
+   *
+   * @public
+   */
+  toDOM (_document = document, hooks = {}, binding) {
+    const fragment = _document.createDocumentFragment()
+    if (binding !== undefined) {
+      binding._createAssociation(fragment, this)
+    }
+    typeListForEach(this, xmlType => {
+      fragment.insertBefore(xmlType.toDOM(_document, hooks, binding), null)
+    })
+    return fragment
+  }
+
+  /**
+   * Inserts new content at an index.
+   *
+   * @example
+   *  // Insert character 'a' at position 0
+   *  xml.insert(0, [new Y.XmlText('text')])
+   *
+   * @param {number} index The index to insert content at
+   * @param {Array<YXmlElement|YXmlText>} content The array of content
+   */
+  insert (index, content) {
+    if (this.doc !== null) {
+      transact(this.doc, transaction => {
+        typeListInsertGenerics(transaction, this, index, content)
+      })
+    } else {
+      // @ts-ignore _prelimContent is defined because this is not yet integrated
+      this._prelimContent.splice(index, 0, ...content)
+    }
+  }
+
+  /**
+   * Deletes elements starting from an index.
+   *
+   * @param {number} index Index at which to start deleting elements
+   * @param {number} [length=1] The number of elements to remove. Defaults to 1.
+   */
+  delete (index, length = 1) {
+    if (this.doc !== null) {
+      transact(this.doc, transaction => {
+        typeListDelete(transaction, this, index, length)
+      })
+    } else {
+      // @ts-ignore _prelimContent is defined because this is not yet integrated
+      this._prelimContent.splice(index, length)
+    }
+  }
+  /**
+   * Transforms this YArray to a JavaScript Array.
+   *
+   * @return {Array<YXmlElement|YXmlText|YXmlHook>}
+   */
+  toArray () {
+    return typeListToArray(this)
+  }
+  /**
+   * Transform the properties of this type to binary and write it to an
+   * BinaryEncoder.
+   *
+   * This is called when this Item is sent to a remote peer.
+   *
+   * @private
+   * @param {encoding.Encoder} encoder The encoder to write data to.
+   */
+  _write (encoder) {
+    encoding.writeVarUint(encoder, YXmlFragmentRefID)
+  }
+}
+
+/**
+ * @param {decoding.Decoder} decoder
+ * @return {YXmlFragment}
+ *
+ * @private
+ * @function
+ */
+export const readYXmlFragment = decoder => new YXmlFragment()

src/types/YXmlHook.js

@@ -47,7 +47,7 @@ export class YXmlHook extends YMap {
    *
    * @public
    */
-  toDom (_document = document, hooks = {}, binding) {
+  toDOM (_document = document, hooks = {}, binding) {
     const hook = hooks[this.hookName]
     let dom
     if (hook !== undefined) {

src/types/YXmlText.js

@@ -9,6 +9,9 @@ import * as decoding from 'lib0/decoding.js' // eslint-disable-line
  * simple formatting information like bold and italic.
  */
 export class YXmlText extends YText {
+  _copy () {
+    return new YXmlText()
+  }
   /**
    * Creates a Dom Element that mirrors this YXmlText.
    *
@@ -24,13 +27,52 @@ export class YXmlText extends YText {
    *
    * @public
    */
-  toDom (_document = document, hooks, binding) {
+  toDOM (_document = document, hooks, binding) {
     const dom = _document.createTextNode(this.toString())
     if (binding !== undefined) {
       binding._createAssociation(dom, this)
     }
     return dom
   }
+
+  toString () {
+    // @ts-ignore
+    return this.toDelta().map(delta => {
+      const nestedNodes = []
+      for (let nodeName in delta.attributes) {
+        const attrs = []
+        for (let key in delta.attributes[nodeName]) {
+          attrs.push({ key, value: delta.attributes[nodeName][key] })
+        }
+        // sort attributes to get a unique order
+        attrs.sort((a, b) => a.key < b.key ? -1 : 1)
+        nestedNodes.push({ nodeName, attrs })
+      }
+      // sort node order to get a unique order
+      nestedNodes.sort((a, b) => a.nodeName < b.nodeName ? -1 : 1)
+      // now convert to dom string
+      let str = ''
+      for (let i = 0; i < nestedNodes.length; i++) {
+        const node = nestedNodes[i]
+        str += `<${node.nodeName}`
+        for (let j = 0; j < node.attrs.length; j++) {
+          const attr = node.attrs[j]
+          str += ` ${attr.key}="${attr.value}"`
+        }
+        str += '>'
+      }
+      str += delta.insert
+      for (let i = nestedNodes.length - 1; i >= 0; i--) {
+        str += `</${nestedNodes[i].nodeName}>`
+      }
+      return str
+    }).join('')
+  }
+
+  toJSON () {
+    return this.toString()
+  }
+
   /**
    * @param {encoding.Encoder} encoder
    *

src/utils/DeleteSet.js

@@ -3,18 +3,18 @@ import {
   findIndexSS,
   createID,
   getState,
-  AbstractItem, StructStore, Transaction, ID // eslint-disable-line
+  splitItem,
+  iterateStructs,
+  Item, GC, StructStore, Transaction, ID // eslint-disable-line
 } from '../internals.js'
 
+import * as array from 'lib0/array.js'
 import * as math from 'lib0/math.js'
 import * as map from 'lib0/map.js'
 import * as encoding from 'lib0/encoding.js'
 import * as decoding from 'lib0/decoding.js'
 
-/**
- * @private
- */
-class DeleteItem {
+export class DeleteItem {
   /**
    * @param {number} clock
    * @param {number} len
@@ -37,8 +37,6 @@ class DeleteItem {
  *   - This DeleteSet is send to other clients
  * - We do not create a DeleteSet when we send a sync message. The DeleteSet message is created directly from StructStore
  * - We read a DeleteSet as part of a sync/update message. In this case the DeleteSet is already sorted and merged.
- *
- * @private
  */
 export class DeleteSet {
   constructor () {
@@ -50,6 +48,24 @@ export class DeleteSet {
   }
 }
 
+/**
+ * Iterate over all structs that the DeleteSet gc's.
+ *
+ * @param {Transaction} transaction
+ * @param {DeleteSet} ds
+ * @param {function(GC|Item):void} f
+ *
+ * @function
+ */
+export const iterateDeletedStructs = (transaction, ds, f) =>
+  ds.clients.forEach((deletes, clientid) => {
+    const structs = /** @type {Array<GC|Item>} */ (transaction.doc.store.clients.get(clientid))
+    for (let i = 0; i < deletes.length; i++) {
+      const del = deletes[i]
+      iterateStructs(transaction, structs, del.clock, del.len, f)
+    }
+  })
+
 /**
  * @param {Array<DeleteItem>} dis
  * @param {number} clock
@@ -120,6 +136,32 @@ export const sortAndMergeDeleteSet = ds => {
   })
 }
 
+/**
+ * @param {Array<DeleteSet>} dss
+ * @return {DeleteSet} A fresh DeleteSet
+ */
+export const mergeDeleteSets = dss => {
+  const merged = new DeleteSet()
+  for (let dssI = 0; dssI < dss.length; dssI++) {
+    dss[dssI].clients.forEach((delsLeft, client) => {
+      if (!merged.clients.has(client)) {
+        // Write all missing keys from current ds and all following.
+        // If merged already contains `client` current ds has already been added.
+        /**
+         * @type {Array<DeleteItem>}
+         */
+        const dels = delsLeft.slice()
+        for (let i = dssI + 1; i < dss.length; i++) {
+          array.appendTo(dels, dss[i].clients.get(client) || [])
+        }
+        merged.clients.set(client, dels)
+      }
+    })
+  }
+  sortAndMergeDeleteSet(merged)
+  return merged
+}
+
 /**
  * @param {DeleteSet} ds
  * @param {ID} id
@@ -132,6 +174,8 @@ export const addToDeleteSet = (ds, id, length) => {
   map.setIfUndefined(ds.clients, id.client, () => []).push(new DeleteItem(id.clock, length))
 }
 
+export const createDeleteSet = () => new DeleteSet()
+
 /**
  * @param {StructStore} ss
  * @return {DeleteSet} Merged and sorted DeleteSet
@@ -140,7 +184,7 @@ export const addToDeleteSet = (ds, id, length) => {
  * @function
  */
 export const createDeleteSetFromStructStore = ss => {
-  const ds = new DeleteSet()
+  const ds = createDeleteSet()
   ss.clients.forEach((structs, client) => {
     /**
      * @type {Array<DeleteItem>}
@@ -187,6 +231,26 @@ export const writeDeleteSet = (encoder, ds) => {
   })
 }
 
+/**
+ * @param {decoding.Decoder} decoder
+ * @return {DeleteSet}
+ *
+ * @private
+ * @function
+ */
+export const readDeleteSet = decoder => {
+  const ds = new DeleteSet()
+  const numClients = decoding.readVarUint(decoder)
+  for (let i = 0; i < numClients; i++) {
+    const client = decoding.readVarUint(decoder)
+    const numberOfDeletes = decoding.readVarUint(decoder)
+    for (let i = 0; i < numberOfDeletes; i++) {
+      addToDeleteSet(ds, createID(client, decoding.readVarUint(decoder)), decoding.readVarUint(decoder))
+    }
+  }
+  return ds
+}
+
 /**
  * @param {decoding.Decoder} decoder
  * @param {Transaction} transaction
@@ -195,7 +259,7 @@ export const writeDeleteSet = (encoder, ds) => {
  * @private
  * @function
  */
-export const readDeleteSet = (decoder, transaction, store) => {
+export const readAndApplyDeleteSet = (decoder, transaction, store) => {
   const unappliedDS = new DeleteSet()
   const numClients = decoding.readVarUint(decoder)
   for (let i = 0; i < numClients; i++) {
@@ -213,13 +277,13 @@ export const readDeleteSet = (decoder, transaction, store) => {
         let index = findIndexSS(structs, clock)
         /**
          * We can ignore the case of GC and Delete structs, because we are going to skip them
-         * @type {AbstractItem}
+         * @type {Item}
          */
         // @ts-ignore
         let struct = structs[index]
         // split the first item if necessary
         if (!struct.deleted && struct.id.clock < clock) {
-          structs.splice(index + 1, 0, struct.splitAt(transaction, clock - struct.id.clock))
+          structs.splice(index + 1, 0, splitItem(transaction, struct, clock - struct.id.clock))
           index++ // increase we now want to use the next struct
         }
         while (index < structs.length) {
@@ -228,7 +292,7 @@ export const readDeleteSet = (decoder, transaction, store) => {
           if (struct.id.clock < clock + len) {
             if (!struct.deleted) {
               if (clock + len < struct.id.clock + struct.length) {
-                structs.splice(index, 0, struct.splitAt(transaction, clock + len - struct.id.clock))
+                structs.splice(index, 0, splitItem(transaction, struct, clock + len - struct.id.clock))
               }
               struct.delete(transaction)
             }
@@ -242,8 +306,9 @@ export const readDeleteSet = (decoder, transaction, store) => {
     }
   }
   if (unappliedDS.clients.size > 0) {
+    // TODO: no need for encoding+decoding ds anymore
     const unappliedDSEncoder = encoding.createEncoder()
     writeDeleteSet(unappliedDSEncoder, unappliedDS)
-    store.pendingDeleteReaders.push(decoding.createDecoder(encoding.toBuffer(unappliedDSEncoder)))
+    store.pendingDeleteReaders.push(decoding.createDecoder(encoding.toUint8Array(unappliedDSEncoder)))
   }
 }

src/utils/Doc.js

@@ -10,7 +10,7 @@ import {
   YMap,
   YXmlFragment,
   transact,
-  Transaction, YEvent // eslint-disable-line
+  Item, Transaction, YEvent // eslint-disable-line
 } from '../internals.js'
 
 import { Observable } from 'lib0/observable.js'
@@ -21,13 +21,13 @@ import * as map from 'lib0/map.js'
  * A Yjs instance handles the state of shared data.
  * @extends Observable<string>
  */
-export class Y extends Observable {
+export class Doc extends Observable {
   /**
    * @param {Object|undefined} conf configuration
    */
   constructor (conf = {}) {
     super()
-    // todo: change to clientId
+    this.gc = conf.gc || true
     this.clientID = random.uint32()
     /**
      * @type {Map<string, AbstractType<YEvent>>}
@@ -39,6 +39,11 @@ export class Y extends Observable {
      * @private
      */
     this._transaction = null
+    /**
+     * @type {Array<Transaction>}
+     * @private
+     */
+    this._transactionCleanups = []
   }
   /**
    * Changes that happen inside of a transaction are bundled. This means that
@@ -47,11 +52,12 @@ export class Y extends Observable {
    * other peers.
    *
    * @param {function(Transaction):void} f The function that should be executed as a transaction
+   * @param {any} [origin] Origin of who started the transaction. Will be stored on transaction.origin
    *
    * @public
    */
-  transact (f) {
-    transact(this, f)
+  transact (f, origin = null) {
+    transact(this, f, origin)
   }
   /**
    * Define a shared data type.
@@ -74,7 +80,7 @@ export class Y extends Observable {
    *   }
    *
    * @param {string} name
-   * @param {Function} TypeConstructor The constructor of the type definition
+   * @param {Function} TypeConstructor The constructor of the type definition. E.g. Y.Text, Y.Array, Y.Map, ...
    * @return {AbstractType<any>} The created type. Constructed with TypeConstructor
    *
    * @public
@@ -89,9 +95,18 @@ export class Y extends Observable {
     const Constr = type.constructor
     if (TypeConstructor !== AbstractType && Constr !== TypeConstructor) {
       if (Constr === AbstractType) {
-        const t = new Constr()
+        // @ts-ignore
+        const t = new TypeConstructor()
         t._map = type._map
+        type._map.forEach(/** @param {Item?} n */ n => {
+          for (; n !== null; n = n.left) {
+            n.parent = t
+          }
+        })
         t._start = type._start
+        for (let n = t._start; n !== null; n = n.right) {
+          n.parent = t
+        }
         t._length = type._length
         this.share.set(name, t)
         t._integrate(this, null)

src/utils/ID.js

@@ -1,5 +1,5 @@
 
-import { AbstractType } from '../internals' // eslint-disable-line
+import { AbstractType } from '../internals.js' // eslint-disable-line
 
 import * as decoding from 'lib0/decoding.js'
 import * as encoding from 'lib0/encoding.js'
@@ -22,16 +22,6 @@ export class ID {
      */
     this.clock = clock
   }
-  /**
-   * @deprecated
-   * @todo remove and adapt relative position implementation
-   */
-  toJSON () {
-    return {
-      client: this.client,
-      clock: this.clock
-    }
-  }
 }
 
 /**
@@ -91,7 +81,7 @@ export const readID = decoder =>
  */
 export const findRootTypeKey = type => {
   // @ts-ignore _y must be defined, otherwise unexpected case
-  for (let [key, value] of type._y.share) {
+  for (let [key, value] of type.doc.share) {
     if (value === type) {
       return key
     }

src/utils/PermanentUserData.js

@@ -0,0 +1,134 @@
+
+import {
+  YArray,
+  YMap,
+  readDeleteSet,
+  writeDeleteSet,
+  createDeleteSet,
+  ID, DeleteSet, YArrayEvent, Transaction, Doc // eslint-disable-line
+} from '../internals.js'
+
+import * as decoding from 'lib0/decoding.js'
+import * as encoding from 'lib0/encoding.js'
+import { mergeDeleteSets, isDeleted } from './DeleteSet.js'
+
+export class PermanentUserData {
+  /**
+   * @param {Doc} doc
+   * @param {string} key
+   */
+  constructor (doc, key = 'users') {
+    const users = doc.getMap(key)
+    /**
+     * @type {Map<string,DeleteSet>}
+     */
+    const dss = new Map()
+    this.yusers = users
+    this.doc = doc
+    /**
+     * Maps from clientid to userDescription
+     *
+     * @type {Map<number,string>}
+     */
+    this.clients = new Map()
+    this.dss = dss
+    /**
+     * @param {YMap<any>} user
+     * @param {string} userDescription
+     */
+    const initUser = (user, userDescription) => {
+      /**
+       * @type {YArray<Uint8Array>}
+       */
+      const ds = user.get('ds')
+      const ids = user.get('ids')
+      const addClientId = /** @param {number} clientid */ clientid => this.clients.set(clientid, userDescription)
+      ds.observe(/** @param {YArrayEvent<any>} event */ event => {
+        event.changes.added.forEach(item => {
+          item.content.getContent().forEach(encodedDs => {
+            if (encodedDs instanceof Uint8Array) {
+              this.dss.set(userDescription, mergeDeleteSets([this.dss.get(userDescription) || createDeleteSet(), readDeleteSet(decoding.createDecoder(encodedDs))]))
+            }
+          })
+        })
+      })
+      this.dss.set(userDescription, mergeDeleteSets(ds.map(encodedDs => readDeleteSet(decoding.createDecoder(encodedDs)))))
+      ids.observe(/** @param {YArrayEvent<any>} event */ event =>
+        event.changes.added.forEach(item => item.content.getContent().forEach(addClientId))
+      )
+      ids.forEach(addClientId)
+    }
+    // observe users
+    users.observe(event => {
+      event.keysChanged.forEach(userDescription =>
+        initUser(users.get(userDescription), userDescription)
+      )
+    })
+    // add intial data
+    users.forEach(initUser)
+  }
+  /**
+   * @param {Doc} doc
+   * @param {number} clientid
+   * @param {string} userDescription
+   */
+  setUserMapping (doc, clientid, userDescription) {
+    const users = this.yusers
+    let user = users.get(userDescription)
+    if (!user) {
+      user = new YMap()
+      user.set('ids', new YArray())
+      user.set('ds', new YArray())
+      users.set(userDescription, user)
+    }
+    user.get('ids').push([clientid])
+    users.observe(event => {
+      const userOverwrite = users.get(userDescription)
+      if (userOverwrite !== user) {
+        // user was overwritten, port all data over to the next user object
+        // @todo Experiment with Y.Sets here
+        user = userOverwrite
+        // @todo iterate over old type
+        this.clients.forEach((_userDescription, clientid) => {
+          if (userDescription === _userDescription) {
+            user.get('ids').push([clientid])
+          }
+        })
+        const encoder = encoding.createEncoder()
+        const ds = this.dss.get(userDescription)
+        if (ds) {
+          writeDeleteSet(encoder, ds)
+          user.get('ds').push([encoding.toUint8Array(encoder)])
+        }
+      }
+    })
+    doc.on('afterTransaction', /** @param {Transaction} transaction */ transaction => {
+      const yds = user.get('ds')
+      const ds = transaction.deleteSet
+      if (transaction.local && ds.clients.size > 0) {
+        const encoder = encoding.createEncoder()
+        writeDeleteSet(encoder, ds)
+        yds.push([encoding.toUint8Array(encoder)])
+      }
+    })
+  }
+  /**
+   * @param {number} clientid
+   * @return {any}
+   */
+  getUserByClientId (clientid) {
+    return this.clients.get(clientid) || null
+  }
+  /**
+   * @param {ID} id
+   * @return {string | null}
+   */
+  getUserByDeletedId (id) {
+    for (const [userDescription, ds] of this.dss) {
+      if (isDeleted(ds, id)) {
+        return userDescription
+      }
+    }
+    return null
+  }
+}

src/utils/RelativePosition.js

@@ -0,0 +1,272 @@
+
+import {
+  createID,
+  writeID,
+  readID,
+  compareIDs,
+  getState,
+  findRootTypeKey,
+  Item,
+  ContentType,
+  followRedone,
+  ID, Doc, AbstractType // eslint-disable-line
+} from '../internals.js'
+
+import * as encoding from 'lib0/encoding.js'
+import * as decoding from 'lib0/decoding.js'
+import * as error from 'lib0/error.js'
+
+/**
+ * A relative position is based on the Yjs model and is not affected by document changes.
+ * E.g. If you place a relative position before a certain character, it will always point to this character.
+ * If you place a relative position at the end of a type, it will always point to the end of the type.
+ *
+ * A numeric position is often unsuited for user selections, because it does not change when content is inserted
+ * before or after.
+ *
+ * ```Insert(0, 'x')('a|bc') = 'xa|bc'``` Where | is the relative position.
+ *
+ * One of the properties must be defined.
+ *
+ * @example
+ *   // Current cursor position is at position 10
+ *   const relativePosition = createRelativePositionFromIndex(yText, 10)
+ *   // modify yText
+ *   yText.insert(0, 'abc')
+ *   yText.delete(3, 10)
+ *   // Compute the cursor position
+ *   const absolutePosition = createAbsolutePositionFromRelativePosition(y, relativePosition)
+ *   absolutePosition.type === yText // => true
+ *   console.log('cursor location is ' + absolutePosition.index) // => cursor location is 3
+ *
+ */
+export class RelativePosition {
+  /**
+   * @param {ID|null} type
+   * @param {string|null} tname
+   * @param {ID|null} item
+   */
+  constructor (type, tname, item) {
+    /**
+     * @type {ID|null}
+     */
+    this.type = type
+    /**
+     * @type {string|null}
+     */
+    this.tname = tname
+    /**
+     * @type {ID | null}
+     */
+    this.item = item
+  }
+}
+
+/**
+ * @param {Object} json
+ * @return {RelativePosition}
+ *
+ * @function
+ */
+export const createRelativePositionFromJSON = json => new RelativePosition(json.type == null ? null : createID(json.type.client, json.type.clock), json.tname || null, json.item == null ? null : createID(json.item.client, json.item.clock))
+
+export class AbsolutePosition {
+  /**
+   * @param {AbstractType<any>} type
+   * @param {number} index
+   */
+  constructor (type, index) {
+    /**
+     * @type {AbstractType<any>}
+     */
+    this.type = type
+    /**
+     * @type {number}
+     */
+    this.index = index
+  }
+}
+
+/**
+ * @param {AbstractType<any>} type
+ * @param {number} index
+ *
+ * @function
+ */
+export const createAbsolutePosition = (type, index) => new AbsolutePosition(type, index)
+
+/**
+ * @param {AbstractType<any>} type
+ * @param {ID|null} item
+ *
+ * @function
+ */
+export const createRelativePosition = (type, item) => {
+  let typeid = null
+  let tname = null
+  if (type._item === null) {
+    tname = findRootTypeKey(type)
+  } else {
+    typeid = type._item.id
+  }
+  return new RelativePosition(typeid, tname, item)
+}
+
+/**
+ * Create a relativePosition based on a absolute position.
+ *
+ * @param {AbstractType<any>} type The base type (e.g. YText or YArray).
+ * @param {number} index The absolute position.
+ * @return {RelativePosition}
+ *
+ * @function
+ */
+export const createRelativePositionFromTypeIndex = (type, index) => {
+  let t = type._start
+  while (t !== null) {
+    if (!t.deleted && t.countable) {
+      if (t.length > index) {
+        // case 1: found position somewhere in the linked list
+        return createRelativePosition(type, createID(t.id.client, t.id.clock + index))
+      }
+      index -= t.length
+    }
+    t = t.right
+  }
+  return createRelativePosition(type, null)
+}
+
+/**
+ * @param {encoding.Encoder} encoder
+ * @param {RelativePosition} rpos
+ *
+ * @function
+ */
+export const writeRelativePosition = (encoder, rpos) => {
+  const { type, tname, item } = rpos
+  if (item !== null) {
+    encoding.writeVarUint(encoder, 0)
+    writeID(encoder, item)
+  } else if (tname !== null) {
+    // case 2: found position at the end of the list and type is stored in y.share
+    encoding.writeUint8(encoder, 1)
+    encoding.writeVarString(encoder, tname)
+  } else if (type !== null) {
+    // case 3: found position at the end of the list and type is attached to an item
+    encoding.writeUint8(encoder, 2)
+    writeID(encoder, type)
+  } else {
+    throw error.unexpectedCase()
+  }
+  return encoder
+}
+
+/**
+ * @param {RelativePosition} rpos
+ * @return {Uint8Array}
+ */
+export const encodeRelativePosition = rpos => {
+  const encoder = encoding.createEncoder()
+  writeRelativePosition(encoder, rpos)
+  return encoding.toUint8Array(encoder)
+}
+
+/**
+ * @param {decoding.Decoder} decoder
+ * @return {RelativePosition|null}
+ *
+ * @function
+ */
+export const readRelativePosition = decoder => {
+  let type = null
+  let tname = null
+  let itemID = null
+  switch (decoding.readVarUint(decoder)) {
+    case 0:
+      // case 1: found position somewhere in the linked list
+      itemID = readID(decoder)
+      break
+    case 1:
+      // case 2: found position at the end of the list and type is stored in y.share
+      tname = decoding.readVarString(decoder)
+      break
+    case 2: {
+      // case 3: found position at the end of the list and type is attached to an item
+      type = readID(decoder)
+    }
+  }
+  return new RelativePosition(type, tname, itemID)
+}
+
+/**
+ * @param {Uint8Array} uint8Array
+ * @return {RelativePosition|null}
+ */
+export const decodeRelativePosition = uint8Array => readRelativePosition(decoding.createDecoder(uint8Array))
+
+/**
+ * @param {RelativePosition} rpos
+ * @param {Doc} doc
+ * @return {AbsolutePosition|null}
+ *
+ * @function
+ */
+export const createAbsolutePositionFromRelativePosition = (rpos, doc) => {
+  const store = doc.store
+  const rightID = rpos.item
+  const typeID = rpos.type
+  const tname = rpos.tname
+  let type = null
+  let index = 0
+  if (rightID !== null) {
+    if (getState(store, rightID.client) <= rightID.clock) {
+      return null
+    }
+    const res = followRedone(store, rightID)
+    const right = res.item
+    if (!(right instanceof Item)) {
+      return null
+    }
+    type = right.parent
+    if (type._item === null || !type._item.deleted) {
+      index = right.deleted || !right.countable ? 0 : res.diff
+      let n = right.left
+      while (n !== null) {
+        if (!n.deleted && n.countable) {
+          index += n.length
+        }
+        n = n.left
+      }
+    }
+  } else {
+    if (tname !== null) {
+      type = doc.get(tname)
+    } else if (typeID !== null) {
+      if (getState(store, typeID.client) <= typeID.clock) {
+        // type does not exist yet
+        return null
+      }
+      const { item } = followRedone(store, typeID)
+      if (item instanceof Item && item.content instanceof ContentType) {
+        type = item.content.type
+      } else {
+        // struct is garbage collected
+        return null
+      }
+    } else {
+      throw error.unexpectedCase()
+    }
+    index = type._length
+  }
+  return createAbsolutePosition(type, index)
+}
+
+/**
+ * @param {RelativePosition|null} a
+ * @param {RelativePosition|null} b
+ *
+ * @function
+ */
+export const compareRelativePositions = (a, b) => a === b || (
+  a !== null && b !== null && a.tname === b.tname && compareIDs(a.item, b.item) && compareIDs(a.type, b.type)
+)

src/utils/Snapshot.js

@@ -1,44 +1,140 @@
 
 import {
-  DeleteSet,
   isDeleted,
-  AbstractItem // eslint-disable-line
+  createDeleteSetFromStructStore,
+  getStateVector,
+  getItemCleanStart,
+  createID,
+  iterateDeletedStructs,
+  writeDeleteSet,
+  writeStateVector,
+  readDeleteSet,
+  readStateVector,
+  createDeleteSet,
+  getState,
+  Transaction, Doc, DeleteSet, Item // eslint-disable-line
 } from '../internals.js'
 
+import * as map from 'lib0/map.js'
+import * as set from 'lib0/set.js'
+import * as encoding from 'lib0/encoding.js'
+import * as decoding from 'lib0/decoding.js'
+
 export class Snapshot {
   /**
-   * @param {DeleteSet} ds delete store
-   * @param {Map<number,number>} sm state map
-   * @param {Map<number,string>} userMap
-   * @private
+   * @param {DeleteSet} ds
+   * @param {Map<number,number>} sv state map
    */
-  constructor (ds, sm, userMap) {
+  constructor (ds, sv) {
     /**
      * @type {DeleteSet}
      * @private
      */
-    this.ds = new DeleteSet()
+    this.ds = ds
     /**
      * State Map
      * @type {Map<number,number>}
      * @private
      */
-    this.sm = sm
-    /**
-     * @type {Map<number,string>}
-     * @private
-     */
-    this.userMap = userMap
+    this.sv = sv
   }
 }
 
 /**
- * @param {AbstractItem} item
+ * @param {Snapshot} snap1
+ * @param {Snapshot} snap2
+ * @return {boolean}
+ */
+export const equalSnapshots = (snap1, snap2) => {
+  const ds1 = snap1.ds.clients
+  const ds2 = snap2.ds.clients
+  const sv1 = snap1.sv
+  const sv2 = snap2.sv
+  if (sv1.size !== sv2.size || ds1.size !== ds2.size) {
+    return false
+  }
+  for (const [key, value] of sv1) {
+    if (sv2.get(key) !== value) {
+      return false
+    }
+  }
+  for (const [client, dsitems1] of ds1) {
+    const dsitems2 = ds2.get(client) || []
+    if (dsitems1.length !== dsitems2.length) {
+      return false
+    }
+    for (let i = 0; i < dsitems1.length; i++) {
+      const dsitem1 = dsitems1[i]
+      const dsitem2 = dsitems2[i]
+      if (dsitem1.clock !== dsitem2.clock || dsitem1.len !== dsitem2.len) {
+        return false
+      }
+    }
+  }
+  return true
+}
+
+/**
+ * @param {Snapshot} snapshot
+ * @return {Uint8Array}
+ */
+export const encodeSnapshot = snapshot => {
+  const encoder = encoding.createEncoder()
+  writeDeleteSet(encoder, snapshot.ds)
+  writeStateVector(encoder, snapshot.sv)
+  return encoding.toUint8Array(encoder)
+}
+
+/**
+ * @param {Uint8Array} buf
+ * @return {Snapshot}
+ */
+export const decodeSnapshot = buf => {
+  const decoder = decoding.createDecoder(buf)
+  return new Snapshot(readDeleteSet(decoder), readStateVector(decoder))
+}
+
+/**
+ * @param {DeleteSet} ds
+ * @param {Map<number,number>} sm
+ * @return {Snapshot}
+ */
+export const createSnapshot = (ds, sm) => new Snapshot(ds, sm)
+
+export const emptySnapshot = createSnapshot(createDeleteSet(), new Map())
+
+/**
+ * @param {Doc} doc
+ * @return {Snapshot}
+ */
+export const snapshot = doc => createSnapshot(createDeleteSetFromStructStore(doc.store), getStateVector(doc.store))
+
+/**
+ * @param {Item} item
  * @param {Snapshot|undefined} snapshot
  *
  * @protected
  * @function
  */
 export const isVisible = (item, snapshot) => snapshot === undefined ? !item.deleted : (
-  snapshot.sm.has(item.id.client) && (snapshot.sm.get(item.id.client) || 0) > item.id.clock && !isDeleted(snapshot.ds, item.id)
+  snapshot.sv.has(item.id.client) && (snapshot.sv.get(item.id.client) || 0) > item.id.clock && !isDeleted(snapshot.ds, item.id)
 )
+
+/**
+ * @param {Transaction} transaction
+ * @param {Snapshot} snapshot
+ */
+export const splitSnapshotAffectedStructs = (transaction, snapshot) => {
+  const meta = map.setIfUndefined(transaction.meta, splitSnapshotAffectedStructs, set.create)
+  const store = transaction.doc.store
+  // check if we already split for this snapshot
+  if (!meta.has(snapshot)) {
+    snapshot.sv.forEach((clock, client) => {
+      if (clock < getState(store, client)) {
+        getItemCleanStart(transaction, createID(client, clock))
+      }
+    })
+    iterateDeletedStructs(transaction, snapshot.ds, item => {})
+    meta.add(snapshot)
+  }
+}

src/utils/StructStore.js

@@ -1,18 +1,18 @@
 
 import {
   GC,
-  Transaction, AbstractStructRef, ID, ItemType, AbstractItem, AbstractStruct // eslint-disable-line
+  splitItem,
+  GCRef, ItemRef, Transaction, ID, Item // eslint-disable-line
 } from '../internals.js'
 
 import * as math from 'lib0/math.js'
 import * as error from 'lib0/error.js'
-import * as encoding from 'lib0/encoding.js'
-import * as decoding from 'lib0/decoding.js'
+import * as decoding from 'lib0/decoding.js' // eslint-disable-line
 
 export class StructStore {
   constructor () {
     /**
-     * @type {Map<number,Array<AbstractStruct>>}
+     * @type {Map<number,Array<GC|Item>>}
      * @private
      */
     this.clients = new Map()
@@ -22,14 +22,14 @@ export class StructStore {
      * We could shift the array of refs instead, but shift is incredible
      * slow in Chrome for arrays with more than 100k elements
      * @see tryResumePendingStructRefs
-     * @type {Map<number,{i:number,refs:Array<AbstractStructRef>}>}
+     * @type {Map<number,{i:number,refs:Array<GCRef|ItemRef>}>}
      * @private
      */
     this.pendingClientsStructRefs = new Map()
     /**
      * Stack of pending structs waiting for struct dependencies
      * Maximum length of stack is structReaders.size
-     * @type {Array<AbstractStructRef>}
+     * @type {Array<GCRef|ItemRef>}
      * @private
      */
     this.pendingStack = []
@@ -51,7 +51,7 @@ export class StructStore {
  * @public
  * @function
  */
-export const getStates = store => {
+export const getStateVector = store => {
   const sm = new Map()
   store.clients.forEach((structs, client) => {
     const struct = structs[structs.length - 1]
@@ -97,7 +97,7 @@ export const integretyCheck = store => {
 
 /**
  * @param {StructStore} store
- * @param {AbstractStruct} struct
+ * @param {GC|Item} struct
  *
  * @private
  * @function
@@ -151,14 +151,14 @@ export const findIndexSS = (structs, clock) => {
  *
  * @param {StructStore} store
  * @param {ID} id
- * @return {AbstractStruct}
+ * @return {GC|Item}
  *
  * @private
  * @function
  */
 export const find = (store, id) => {
   /**
-   * @type {Array<AbstractStruct>}
+   * @type {Array<GC|Item>}
    */
   // @ts-ignore
   const structs = store.clients.get(id.client)
@@ -170,7 +170,7 @@ export const find = (store, id) => {
  *
  * @param {StructStore} store
  * @param {ID} id
- * @return {AbstractItem}
+ * @return {Item}
  *
  * @private
  * @function
@@ -179,45 +179,33 @@ export const find = (store, id) => {
 export const getItem = (store, id) => find(store, id)
 
 /**
- * Expects that id is actually in store. This function throws or is an infinite loop otherwise.
- *
- * @param {StructStore} store
- * @param {ID} id
- * @return {ItemType}
- *
- * @private
- * @function
+ * @param {Transaction} transaction
+ * @param {Array<Item|GC>} structs
+ * @param {number} clock
  */
-// @ts-ignore
-export const getItemType = (store, id) => find(store, id)
+export const findIndexCleanStart = (transaction, structs, clock) => {
+  const index = findIndexSS(structs, clock)
+  let struct = structs[index]
+  if (struct.id.clock < clock && struct instanceof Item) {
+    structs.splice(index + 1, 0, splitItem(transaction, struct, clock - struct.id.clock))
+    return index + 1
+  }
+  return index
+}
 
 /**
  * Expects that id is actually in store. This function throws or is an infinite loop otherwise.
  *
  * @param {Transaction} transaction
- * @param {StructStore} store
  * @param {ID} id
- * @return {AbstractItem}
+ * @return {Item}
  *
  * @private
  * @function
  */
-export const getItemCleanStart = (transaction, store, id) => {
-  /**
-   * @type {Array<AbstractItem>}
-   */
-  // @ts-ignore
-  const structs = store.clients.get(id.client)
-  const index = findIndexSS(structs, id.clock)
-  /**
-   * @type {AbstractItem}
-   */
-  let struct = structs[index]
-  if (struct.id.clock < id.clock && struct.constructor !== GC) {
-    struct = struct.splitAt(transaction, id.clock - struct.id.clock)
-    structs.splice(index + 1, 0, struct)
-  }
-  return struct
+export const getItemCleanStart = (transaction, id) => {
+  const structs = /** @type {Array<Item>} */ (transaction.doc.store.clients.get(id.client))
+  return structs[findIndexCleanStart(transaction, structs, id.clock)]
 }
 
 /**
@@ -226,21 +214,21 @@ export const getItemCleanStart = (transaction, store, id) => {
  * @param {Transaction} transaction
  * @param {StructStore} store
  * @param {ID} id
- * @return {AbstractItem}
+ * @return {Item}
  *
  * @private
  * @function
  */
 export const getItemCleanEnd = (transaction, store, id) => {
   /**
-   * @type {Array<AbstractItem>}
+   * @type {Array<Item>}
    */
   // @ts-ignore
   const structs = store.clients.get(id.client)
   const index = findIndexSS(structs, id.clock)
   const struct = structs[index]
   if (id.clock !== struct.id.clock + struct.length - 1 && struct.constructor !== GC) {
-    structs.splice(index + 1, 0, struct.splitAt(transaction, id.clock - struct.id.clock + 1))
+    structs.splice(index + 1, 0, splitItem(transaction, struct, id.clock - struct.id.clock + 1))
   }
   return struct
 }
@@ -248,56 +236,40 @@ export const getItemCleanEnd = (transaction, store, id) => {
 /**
  * Replace `item` with `newitem` in store
  * @param {StructStore} store
- * @param {AbstractStruct} struct
- * @param {AbstractStruct} newStruct
+ * @param {GC|Item} struct
+ * @param {GC|Item} newStruct
  *
  * @private
  * @function
  */
 export const replaceStruct = (store, struct, newStruct) => {
-  /**
-   * @type {Array<AbstractStruct>}
-   */
-  // @ts-ignore
-  const structs = store.clients.get(struct.id.client)
+  const structs = /** @type {Array<GC|Item>} */ (store.clients.get(struct.id.client))
   structs[findIndexSS(structs, struct.id.clock)] = newStruct
 }
 
 /**
- * Read StateMap from Decoder and return as Map
+ * Iterate over a range of structs
  *
- * @param {decoding.Decoder} decoder
- * @return {Map<number,number>}
+ * @param {Transaction} transaction
+ * @param {Array<Item|GC>} structs
+ * @param {number} clockStart Inclusive start
+ * @param {number} len
+ * @param {function(GC|Item):void} f
  *
- * @private
  * @function
  */
-export const readStatesAsMap = decoder => {
-  const ss = new Map()
-  const ssLength = decoding.readVarUint(decoder)
-  for (let i = 0; i < ssLength; i++) {
-    const client = decoding.readVarUint(decoder)
-    const clock = decoding.readVarUint(decoder)
-    ss.set(client, clock)
+export const iterateStructs = (transaction, structs, clockStart, len, f) => {
+  if (len === 0) {
+    return
   }
-  return ss
-}
-
-/**
- * Write StateMap to Encoder
- *
- * @param {encoding.Encoder} encoder
- * @param {StructStore} store
- *
- * @private
- * @function
- */
-export const writeStates = (encoder, store) => {
-  encoding.writeVarUint(encoder, store.clients.size)
-  store.clients.forEach((structs, client) => {
-    const id = structs[structs.length - 1].id
-    encoding.writeVarUint(encoder, id.client)
-    encoding.writeVarUint(encoder, id.clock)
-  })
-  return encoder
+  const clockEnd = clockStart + len
+  let index = findIndexCleanStart(transaction, structs, clockStart)
+  let struct
+  do {
+    struct = structs[index++]
+    if (clockEnd < struct.id.clock + struct.length) {
+      findIndexCleanStart(transaction, structs, clockEnd)
+    }
+    f(struct)
+  } while (index < structs.length && structs[index].id.clock < clockEnd)
 }

src/utils/Transaction.js

@@ -6,17 +6,18 @@ import {
   writeDeleteSet,
   DeleteSet,
   sortAndMergeDeleteSet,
-  getStates,
+  getStateVector,
   findIndexSS,
   callEventHandlerListeners,
-  AbstractItem,
-  ItemDeleted,
-  ID, AbstractType, AbstractStruct, YEvent, Y // eslint-disable-line
+  Item,
+  ID, AbstractType, AbstractStruct, YEvent, Doc // eslint-disable-line
 } from '../internals.js'
 
 import * as encoding from 'lib0/encoding.js'
 import * as map from 'lib0/map.js'
 import * as math from 'lib0/math.js'
+import * as set from 'lib0/set.js'
+import { callAll } from 'lib0/function.js'
 
 /**
  * A transaction is created for every change on the Yjs model. It is possible
@@ -44,14 +45,16 @@ import * as math from 'lib0/math.js'
  */
 export class Transaction {
   /**
-   * @param {Y} y
+   * @param {Doc} doc
+   * @param {any} origin
+   * @param {boolean} local
    */
-  constructor (y) {
+  constructor (doc, origin, local) {
     /**
      * The Yjs instance.
-     * @type {Y}
+     * @type {Doc}
      */
-    this.y = y
+    this.doc = doc
     /**
      * Describes the set of deleted items by ids
      * @type {DeleteSet}
@@ -61,7 +64,7 @@ export class Transaction {
      * Holds the state before the transaction started.
      * @type {Map<Number,Number>}
      */
-    this.beforeState = getStates(y.store)
+    this.beforeState = getStateVector(doc.store)
     /**
      * Holds the state after the transaction.
      * @type {Map<Number,Number>}
@@ -80,32 +83,40 @@ export class Transaction {
      * @type {Map<AbstractType<YEvent>,Array<YEvent>>}
      */
     this.changedParentTypes = new Map()
-    /**
-     * @type {encoding.Encoder|null}
-     * @private
-     */
-    this._updateMessage = null
     /**
      * @type {Set<ID>}
      * @private
      */
     this._mergeStructs = new Set()
+    /**
+     * @type {any}
+     */
+    this.origin = origin
+    /**
+     * Stores meta information on the transaction
+     * @type {Map<any,any>}
+     */
+    this.meta = new Map()
+    /**
+     * Whether this change originates from this doc.
+     * @type {boolean}
+     */
+    this.local = local
   }
-  /**
-   * @type {encoding.Encoder|null}
-   * @public
-   */
-  get updateMessage () {
-    // only create if content was added in transaction (state or ds changed)
-    if (this._updateMessage === null && (this.deleteSet.clients.size > 0 || map.any(this.afterState, (clock, client) => this.beforeState.get(client) !== clock))) {
-      const encoder = encoding.createEncoder()
-      sortAndMergeDeleteSet(this.deleteSet)
-      writeStructsFromTransaction(encoder, this)
-      writeDeleteSet(encoder, this.deleteSet)
-      this._updateMessage = encoder
-    }
-    return this._updateMessage
+}
+
+/**
+ * @param {Transaction} transaction
+ */
+export const computeUpdateMessageFromTransaction = transaction => {
+  if (transaction.deleteSet.clients.size === 0 && !map.any(transaction.afterState, (clock, client) => transaction.beforeState.get(client) !== clock)) {
+    return null
   }
+  const encoder = encoding.createEncoder()
+  sortAndMergeDeleteSet(transaction.deleteSet)
+  writeStructsFromTransaction(encoder, transaction)
+  writeDeleteSet(encoder, transaction.deleteSet)
+  return encoder
 }
 
 /**
@@ -115,79 +126,81 @@ export class Transaction {
  * @function
  */
 export const nextID = transaction => {
-  const y = transaction.y
+  const y = transaction.doc
   return createID(y.clientID, getState(y.store, y.clientID))
 }
 
 /**
- * Implements the functionality of `y.transact(()=>{..})`
+ * If `type.parent` was added in current transaction, `type` technically
+ * did not change, it was just added and we should not fire events for `type`.
  *
- * @param {Y} y
- * @param {function(Transaction):void} f
- *
- * @private
- * @function
+ * @param {Transaction} transaction
+ * @param {AbstractType<YEvent>} type
+ * @param {string|null} parentSub
  */
-export const transact = (y, f) => {
-  let initialCall = false
-  if (y._transaction === null) {
-    initialCall = true
-    y._transaction = new Transaction(y)
-    y.emit('beforeTransaction', [y._transaction, y])
+export const addChangedTypeToTransaction = (transaction, type, parentSub) => {
+  const item = type._item
+  if (item === null || (item.id.clock < (transaction.beforeState.get(item.id.client) || 0) && !item.deleted)) {
+    map.setIfUndefined(transaction.changed, type, set.create).add(parentSub)
   }
-  const transaction = y._transaction
-  try {
-    f(transaction)
-  } finally {
-    if (initialCall) {
-      y._transaction = null
-      y.emit('beforeObserverCalls', [transaction, y])
-      // emit change events on changed types
-      transaction.changed.forEach((subs, itemtype) => {
-        itemtype._callObserver(transaction, subs)
-      })
-      transaction.changedParentTypes.forEach((events, type) => {
-        events = events
-          .filter(event =>
-            event.target._item === null || !event.target._item.deleted
-          )
-        events
-          .forEach(event => {
-            event.currentTarget = type
-          })
-        // we don't need to check for events.length
-        // because we know it has at least one element
-        callEventHandlerListeners(type._dEH, events, transaction)
-      })
-      // only call afterTransaction listeners if anything changed
-      transaction.afterState = getStates(transaction.y.store)
-      // when all changes & events are processed, emit afterTransaction event
-      // transaction cleanup
-      const store = transaction.y.store
-      const ds = transaction.deleteSet
-      // replace deleted items with ItemDeleted / GC
+}
+
+/**
+ * @param {Array<Transaction>} transactionCleanups
+ * @param {number} i
+ */
+const cleanupTransactions = (transactionCleanups, i) => {
+  if (i < transactionCleanups.length) {
+    const transaction = transactionCleanups[i]
+    const doc = transaction.doc
+    const store = doc.store
+    const ds = transaction.deleteSet
+    try {
       sortAndMergeDeleteSet(ds)
-      y.emit('afterTransaction', [transaction, y])
-      for (const [client, deleteItems] of ds.clients) {
-        /**
-         * @type {Array<AbstractStruct>}
-         */
-        // @ts-ignore
-        const structs = store.clients.get(client)
-        for (let di = 0; di < deleteItems.length; di++) {
-          const deleteItem = deleteItems[di]
-          for (let si = findIndexSS(structs, deleteItem.clock); si < structs.length; si++) {
-            const struct = structs[si]
-            if (deleteItem.clock + deleteItem.len <= struct.id.clock) {
-              break
-            }
-            if (struct.deleted && struct instanceof AbstractItem && (struct.constructor !== ItemDeleted || (struct.parent._item !== null && struct.parent._item.deleted))) {
-              // check if we can GC
-              struct.gc(transaction, store)
-            }
+      transaction.afterState = getStateVector(transaction.doc.store)
+      doc._transaction = null
+      doc.emit('beforeObserverCalls', [transaction, doc])
+      /**
+       * An array of event callbacks.
+       *
+       * Each callback is called even if the other ones throw errors.
+       *
+       * @type {Array<function():void>}
+       */
+      const fs = []
+      // observe events on changed types
+      transaction.changed.forEach((subs, itemtype) =>
+        fs.push(() => {
+          if (itemtype._item === null || !itemtype._item.deleted) {
+            itemtype._callObserver(transaction, subs)
           }
-        }
-      }
+        })
+      )
+      fs.push(() => {
+        // deep observe events
+        transaction.changedParentTypes.forEach((events, type) =>
+          fs.push(() => {
+            // We need to think about the possibility that the user transforms the
+            // Y.Doc in the event.
+            if (type._item === null || !type._item.deleted) {
+              events = events
+                .filter(event =>
+                  event.target._item === null || !event.target._item.deleted
+                )
+              events
+                .forEach(event => {
+                  event.currentTarget = type
+                })
+              // We don't need to check for events.length
+              // because we know it has at least one element
+              callEventHandlerListeners(type._dEH, events, transaction)
+            }
+          })
+        )
+        fs.push(() => doc.emit('afterTransaction', [transaction, doc]))
+      })
+      callAll(fs, [])
+    } finally {
       /**
        * @param {Array<AbstractStruct>} structs
        * @param {number} pos
@@ -198,22 +211,59 @@ export const transact = (y, f) => {
         if (left.deleted === right.deleted && left.constructor === right.constructor) {
           if (left.mergeWith(right)) {
             structs.splice(pos, 1)
-            if (right instanceof AbstractItem && right.parentSub !== null && right.parent._map.get(right.parentSub) === right) {
-              // @ts-ignore we already did a constructor check above
-              right.parent._map.set(right.parentSub, left)
+            if (right instanceof Item && right.parentSub !== null && right.parent._map.get(right.parentSub) === right) {
+              right.parent._map.set(right.parentSub, /** @type {Item} */ (left))
             }
           }
         }
       }
+      // Replace deleted items with ItemDeleted / GC.
+      // This is where content is actually remove from the Yjs Doc.
+      if (doc.gc) {
+        for (const [client, deleteItems] of ds.clients) {
+          const structs = /** @type {Array<AbstractStruct>} */ (store.clients.get(client))
+          for (let di = deleteItems.length - 1; di >= 0; di--) {
+            const deleteItem = deleteItems[di]
+            const endDeleteItemClock = deleteItem.clock + deleteItem.len
+            for (
+              let si = findIndexSS(structs, deleteItem.clock), struct = structs[si];
+              si < structs.length && struct.id.clock < endDeleteItemClock;
+              struct = structs[++si]
+            ) {
+              const struct = structs[si]
+              if (deleteItem.clock + deleteItem.len <= struct.id.clock) {
+                break
+              }
+              if (struct instanceof Item && struct.deleted && !struct.keep) {
+                struct.gc(store, false)
+              }
+            }
+          }
+        }
+      }
+      // try to merge deleted / gc'd items
+      // merge from right to left for better efficiecy and so we don't miss any merge targets
+      for (const [client, deleteItems] of ds.clients) {
+        const structs = /** @type {Array<AbstractStruct>} */ (store.clients.get(client))
+        for (let di = deleteItems.length - 1; di >= 0; di--) {
+          const deleteItem = deleteItems[di]
+          // start with merging the item next to the last deleted item
+          const mostRightIndexToCheck = math.min(structs.length - 1, 1 + findIndexSS(structs, deleteItem.clock + deleteItem.len - 1))
+          for (
+            let si = mostRightIndexToCheck, struct = structs[si];
+            si > 0 && struct.id.clock >= deleteItem.clock;
+            struct = structs[--si]
+          ) {
+            tryToMergeWithLeft(structs, si)
+          }
+        }
+      }
+
       // on all affected store.clients props, try to merge
       for (const [client, clock] of transaction.afterState) {
         const beforeClock = transaction.beforeState.get(client) || 0
         if (beforeClock !== clock) {
-          /**
-           * @type {Array<AbstractStruct>}
-           */
-          // @ts-ignore
-          const structs = store.clients.get(client)
+          const structs = /** @type {Array<AbstractStruct>} */ (store.clients.get(client))
           // we iterate from right to left so we can safely remove entries
           const firstChangePos = math.max(findIndexSS(structs, beforeClock), 1)
           for (let i = structs.length - 1; i >= firstChangePos; i--) {
@@ -222,14 +272,12 @@ export const transact = (y, f) => {
         }
       }
       // try to merge mergeStructs
+      // @todo: it makes more sense to transform mergeStructs to a DS, sort it, and merge from right to left
+      //        but at the moment DS does not handle duplicates
       for (const mid of transaction._mergeStructs) {
         const client = mid.client
         const clock = mid.clock
-        /**
-         * @type {Array<AbstractStruct>}
-         */
-        // @ts-ignore
-        const structs = store.clients.get(client)
+        const structs = /** @type {Array<AbstractStruct>} */ (store.clients.get(client))
         const replacedStructPos = findIndexSS(structs, clock)
         if (replacedStructPos + 1 < structs.length) {
           tryToMergeWithLeft(structs, replacedStructPos + 1)
@@ -238,7 +286,55 @@ export const transact = (y, f) => {
           tryToMergeWithLeft(structs, replacedStructPos)
         }
       }
-      y.emit('afterTransactionCleanup', [transaction, y])
+      // @todo Merge all the transactions into one and provide send the data as a single update message
+      doc.emit('afterTransactionCleanup', [transaction, doc])
+      if (doc._observers.has('update')) {
+        const updateMessage = computeUpdateMessageFromTransaction(transaction)
+        if (updateMessage !== null) {
+          doc.emit('update', [encoding.toUint8Array(updateMessage), transaction.origin, doc])
+        }
+      }
+      if (transactionCleanups.length <= i + 1) {
+        doc._transactionCleanups = []
+      } else {
+        cleanupTransactions(transactionCleanups, i + 1)
+      }
+    }
+  }
+}
+
+/**
+ * Implements the functionality of `y.transact(()=>{..})`
+ *
+ * @param {Doc} doc
+ * @param {function(Transaction):void} f
+ * @param {any} [origin=true]
+ *
+ * @private
+ * @function
+ */
+export const transact = (doc, f, origin = null, local = true) => {
+  const transactionCleanups = doc._transactionCleanups
+  let initialCall = false
+  if (doc._transaction === null) {
+    initialCall = true
+    doc._transaction = new Transaction(doc, origin, local)
+    transactionCleanups.push(doc._transaction)
+    doc.emit('beforeTransaction', [doc._transaction, doc])
+  }
+  try {
+    f(doc._transaction)
+  } finally {
+    if (initialCall && transactionCleanups[0] === doc._transaction) {
+      // The first transaction ended, now process observer calls.
+      // Observer call may create new transactions for which we need to call the observers and do cleanup.
+      // We don't want to nest these calls, so we execute these calls one after
+      // another.
+      // Also we need to ensure that all cleanups are called, even if the
+      // observes throw errors.
+      // This file is full of hacky try {} finally {} blocks to ensure that an
+      // event can throw errors and also that the cleanup is called.
+      cleanupTransactions(transactionCleanups, 0)
     }
   }
 }

src/utils/UndoManager.js

@@ -1,202 +1,264 @@
-// @ts-nocheck
-
 import {
+  mergeDeleteSets,
+  iterateDeletedStructs,
+  keepItem,
+  transact,
+  redoItem,
+  iterateStructs,
   isParentOf,
   createID,
-  transact
+  followRedone,
+  getItemCleanStart,
+  getState,
+  Transaction, Doc, Item, GC, DeleteSet, AbstractType // eslint-disable-line
 } from '../internals.js'
 
-/**
- * @private
- */
-class ReverseOperation {
-  constructor (y, transaction, bindingInfos) {
-    this.created = new Date()
-    const beforeState = transaction.beforeState
-    if (beforeState.has(y.userID)) {
-      this.toState = createID(y.userID, y.ss.getState(y.userID) - 1)
-      this.fromState = createID(y.userID, beforeState.get(y.userID))
-    } else {
-      this.toState = null
-      this.fromState = null
-    }
-    this.deletedStructs = new Set()
-    transaction.deletedStructs.forEach(struct => {
-      this.deletedStructs.add({
-        from: struct._id,
-        len: struct._length
-      })
-    })
-    /**
-     * Maps from binding to binding information (e.g. cursor information)
-     */
-    this.bindingInfos = bindingInfos
-  }
-}
+import * as time from 'lib0/time.js'
+import { Observable } from 'lib0/observable.js'
 
-/**
- * @private
- * @function
- */
-function applyReverseOperation (y, scope, reverseBuffer) {
-  let performedUndo = false
-  let undoOp = null
-  transact(y, () => {
-    while (!performedUndo && reverseBuffer.length > 0) {
-      undoOp = reverseBuffer.pop()
-      // make sure that it is possible to iterate {from}-{to}
-      if (undoOp.fromState !== null) {
-        y.os.getItemCleanStart(undoOp.fromState)
-        y.os.getItemCleanEnd(undoOp.toState)
-        y.os.iterate(undoOp.fromState, undoOp.toState, op => {
-          while (op._deleted && op._redone !== null) {
-            op = op._redone
-          }
-          if (op._deleted === false && isParentOf(scope, op)) {
-            performedUndo = true
-            op._delete(y)
-          }
-        })
-      }
-      const redoitems = new Set()
-      for (let del of undoOp.deletedStructs) {
-        const fromState = del.from
-        const toState = createID(fromState.user, fromState.clock + del.len - 1)
-        y.os.getItemCleanStart(fromState)
-        y.os.getItemCleanEnd(toState)
-        y.os.iterate(fromState, toState, op => {
-          if (
-            isParentOf(scope, op) &&
-            op._parent !== y &&
-            (
-              op._id.user !== y.userID ||
-              undoOp.fromState === null ||
-              op._id.clock < undoOp.fromState.clock ||
-              op._id.clock > undoOp.toState.clock
-            )
-          ) {
-            redoitems.add(op)
-          }
-        })
-      }
-      redoitems.forEach(op => {
-        const opUndone = op._redo(y, redoitems)
-        performedUndo = performedUndo || opUndone
-      })
-    }
-  })
-  if (performedUndo && undoOp !== null) {
-    // should be performed after the undo transaction
-    undoOp.bindingInfos.forEach((info, binding) => {
-      binding._restoreUndoStackInfo(info)
-    })
-  }
-  return performedUndo
-}
-
-/**
- * Saves a history of locally applied operations. The UndoManager handles the
- * undoing and redoing of locally created changes.
- *
- * @private
- * @function
- */
-export class UndoManager {
+class StackItem {
   /**
-   * @param {YType} scope The scope on which to listen for changes.
-   * @param {Object} options Optionally provided configuration.
+   * @param {DeleteSet} ds
+   * @param {number} start clock start of the local client
+   * @param {number} len
    */
-  constructor (scope, options = {}) {
-    this.options = options
-    this._bindings = new Set(options.bindings)
-    options.captureTimeout = options.captureTimeout == null ? 500 : options.captureTimeout
-    this._undoBuffer = []
-    this._redoBuffer = []
-    this._scope = scope
-    this._undoing = false
-    this._redoing = false
-    this._lastTransactionWasUndo = false
-    const y = scope._y
-    this.y = y
-    let bindingInfos
-    y.on('beforeTransaction', (y, transaction, remote) => {
-      if (!remote) {
-        // Store binding information before transaction is executed
-        // By restoring the binding information, we can make sure that the state
-        // before the transaction can be recovered
-        bindingInfos = new Map()
-        this._bindings.forEach(binding => {
-          bindingInfos.set(binding, binding._getUndoStackInfo())
-        })
-      }
-    })
-    y.on('afterTransaction', (y, transaction, remote) => {
-      if (!remote && transaction.changedParentTypes.has(scope)) {
-        let reverseOperation = new ReverseOperation(y, transaction, bindingInfos)
-        if (!this._undoing) {
-          let lastUndoOp = this._undoBuffer.length > 0 ? this._undoBuffer[this._undoBuffer.length - 1] : null
-          if (
-            this._redoing === false &&
-            this._lastTransactionWasUndo === false &&
-            lastUndoOp !== null &&
-            ((options.captureTimeout < 0) || (reverseOperation.created.getTime() - lastUndoOp.created.getTime()) <= options.captureTimeout)
-          ) {
-            lastUndoOp.created = reverseOperation.created
-            if (reverseOperation.toState !== null) {
-              lastUndoOp.toState = reverseOperation.toState
-              if (lastUndoOp.fromState === null) {
-                lastUndoOp.fromState = reverseOperation.fromState
-              }
-            }
-            reverseOperation.deletedStructs.forEach(lastUndoOp.deletedStructs.add, lastUndoOp.deletedStructs)
-          } else {
-            this._lastTransactionWasUndo = false
-            this._undoBuffer.push(reverseOperation)
-          }
-          if (!this._redoing) {
-            this._redoBuffer = []
-          }
-        } else {
-          this._lastTransactionWasUndo = true
-          this._redoBuffer.push(reverseOperation)
+  constructor (ds, start, len) {
+    this.ds = ds
+    this.start = start
+    this.len = len
+    /**
+     * Use this to save and restore metadata like selection range
+     */
+    this.meta = new Map()
+  }
+}
+
+/**
+ * @param {UndoManager} undoManager
+ * @param {Array<StackItem>} stack
+ * @param {string} eventType
+ * @return {StackItem?}
+ */
+const popStackItem = (undoManager, stack, eventType) => {
+  /**
+   * Whether a change happened
+   * @type {StackItem?}
+   */
+  let result = null
+  const doc = undoManager.doc
+  const scope = undoManager.scope
+  transact(doc, transaction => {
+    while (stack.length > 0 && result === null) {
+      const store = doc.store
+      const clientID = doc.clientID
+      const stackItem = /** @type {StackItem} */ (stack.pop())
+      const stackStartClock = stackItem.start
+      const stackEndClock = stackItem.start + stackItem.len
+      const itemsToRedo = new Set()
+      // @todo iterateStructs should not need the structs parameter
+      const structs = /** @type {Array<GC|Item>} */ (store.clients.get(clientID))
+      let performedChange = false
+      if (stackStartClock !== stackEndClock) {
+        // make sure structs don't overlap with the range of created operations [stackItem.start, stackItem.start + stackItem.end)
+        getItemCleanStart(transaction, createID(clientID, stackStartClock))
+        if (stackEndClock < getState(doc.store, clientID)) {
+          getItemCleanStart(transaction, createID(clientID, stackEndClock))
         }
       }
+      iterateDeletedStructs(transaction, stackItem.ds, struct => {
+        if (
+          struct instanceof Item &&
+          scope.some(type => isParentOf(type, struct)) &&
+          // Never redo structs in [stackItem.start, stackItem.start + stackItem.end) because they were created and deleted in the same capture interval.
+          !(struct.id.client === clientID && struct.id.clock >= stackStartClock && struct.id.clock < stackEndClock)
+        ) {
+          itemsToRedo.add(struct)
+        }
+      })
+      itemsToRedo.forEach(struct => {
+        performedChange = redoItem(transaction, struct, itemsToRedo) !== null || performedChange
+      })
+      /**
+       * @type {Array<Item>}
+       */
+      const itemsToDelete = []
+      iterateStructs(transaction, structs, stackStartClock, stackItem.len, struct => {
+        if (struct instanceof Item) {
+          if (struct.redone !== null) {
+            let { item, diff } = followRedone(store, struct.id)
+            if (diff > 0) {
+              item = getItemCleanStart(transaction, createID(item.id.client, item.id.clock + diff))
+            }
+            if (item.length > stackItem.len) {
+              getItemCleanStart(transaction, createID(item.id.client, stackEndClock))
+            }
+            struct = item
+          }
+          if (!struct.deleted && scope.some(type => isParentOf(type, /** @type {Item} */ (struct)))) {
+            itemsToDelete.push(struct)
+          }
+        }
+      })
+      // We want to delete in reverse order so that children are deleted before
+      // parents, so we have more information available when items are filtered.
+      for (let i = itemsToDelete.length - 1; i >= 0; i--) {
+        const item = itemsToDelete[i]
+        if (undoManager.deleteFilter(item)) {
+          item.delete(transaction)
+          performedChange = true
+        }
+      }
+      result = stackItem
+      if (result != null) {
+        undoManager.emit('stack-item-popped', [{ stackItem: result, type: eventType }, undoManager])
+      }
+    }
+  }, undoManager)
+  return result
+}
+
+/**
+ * @typedef {Object} UndoManagerOptions
+ * @property {number} [UndoManagerOptions.captureTimeout=500]
+ * @property {function(Item):boolean} [UndoManagerOptions.deleteFilter=()=>true] Sometimes
+ * it is necessary to filter whan an Undo/Redo operation can delete. If this
+ * filter returns false, the type/item won't be deleted even it is in the
+ * undo/redo scope.
+ * @property {Set<any>} [UndoManagerOptions.trackedOrigins=new Set([null])]
+ */
+
+/**
+ * Fires 'stack-item-added' event when a stack item was added to either the undo- or
+ * the redo-stack. You may store additional stack information via the
+ * metadata property on `event.stackItem.meta` (it is a `Map` of metadata properties).
+ * Fires 'stack-item-popped' event when a stack item was popped from either the
+ * undo- or the redo-stack. You may restore the saved stack information from `event.stackItem.meta`.
+ *
+ * @extends {Observable<'stack-item-added'|'stack-item-popped'>}
+ */
+export class UndoManager extends Observable {
+  /**
+   * @param {AbstractType<any>|Array<AbstractType<any>>} typeScope Accepts either a single type, or an array of types
+   * @param {UndoManagerOptions} options
+   */
+  constructor (typeScope, { captureTimeout, deleteFilter = () => true, trackedOrigins = new Set([null]) } = {}) {
+    if (captureTimeout == null) {
+      captureTimeout = 500
+    }
+    super()
+    this.scope = typeScope instanceof Array ? typeScope : [typeScope]
+    this.deleteFilter = deleteFilter
+    trackedOrigins.add(this)
+    this.trackedOrigins = trackedOrigins
+    /**
+     * @type {Array<StackItem>}
+     */
+    this.undoStack = []
+    /**
+     * @type {Array<StackItem>}
+     */
+    this.redoStack = []
+    /**
+     * Whether the client is currently undoing (calling UndoManager.undo)
+     *
+     * @type {boolean}
+     */
+    this.undoing = false
+    this.redoing = false
+    this.doc = /** @type {Doc} */ (this.scope[0].doc)
+    this.lastChange = 0
+    this.doc.on('afterTransaction', /** @param {Transaction} transaction */ transaction => {
+      // Only track certain transactions
+      if (!this.scope.some(type => transaction.changedParentTypes.has(type)) || (!this.trackedOrigins.has(transaction.origin) && (!transaction.origin || !this.trackedOrigins.has(transaction.origin.constructor)))) {
+        return
+      }
+      const undoing = this.undoing
+      const redoing = this.redoing
+      const stack = undoing ? this.redoStack : this.undoStack
+      if (undoing) {
+        this.stopCapturing() // next undo should not be appended to last stack item
+      } else if (!redoing) {
+        // neither undoing nor redoing: delete redoStack
+        this.redoStack = []
+      }
+      const beforeState = transaction.beforeState.get(this.doc.clientID) || 0
+      const afterState = transaction.afterState.get(this.doc.clientID) || 0
+      const now = time.getUnixTime()
+      if (now - this.lastChange < captureTimeout && stack.length > 0 && !undoing && !redoing) {
+        // append change to last stack op
+        const lastOp = stack[stack.length - 1]
+        lastOp.ds = mergeDeleteSets([lastOp.ds, transaction.deleteSet])
+        lastOp.len = afterState - lastOp.start
+      } else {
+        // create a new stack op
+        stack.push(new StackItem(transaction.deleteSet, beforeState, afterState - beforeState))
+      }
+      if (!undoing && !redoing) {
+        this.lastChange = now
+      }
+      // make sure that deleted structs are not gc'd
+      iterateDeletedStructs(transaction, transaction.deleteSet, /** @param {Item|GC} item */ item => {
+        if (item instanceof Item && this.scope.some(type => isParentOf(type, item))) {
+          keepItem(item)
+        }
+      })
+      this.emit('stack-item-added', [{ stackItem: stack[stack.length - 1], origin: transaction.origin, type: undoing ? 'redo' : 'undo' }, this])
     })
   }
 
   /**
-   * Enforce that the next change is created as a separate item in the undo stack
+   * UndoManager merges Undo-StackItem if they are created within time-gap
+   * smaller than `options.captureTimeout`. Call `um.stopCapturing()` so that the next
+   * StackItem won't be merged.
+   *
+   *
+   * @example
+   *     // without stopCapturing
+   *     ytext.insert(0, 'a')
+   *     ytext.insert(1, 'b')
+   *     um.undo()
+   *     ytext.toString() // => '' (note that 'ab' was removed)
+   *     // with stopCapturing
+   *     ytext.insert(0, 'a')
+   *     um.stopCapturing()
+   *     ytext.insert(0, 'b')
+   *     um.undo()
+   *     ytext.toString() // => 'a' (note that only 'b' was removed)
    *
-   * @private
-   * @function
    */
-  flushChanges () {
-    this._lastTransactionWasUndo = true
+  stopCapturing () {
+    this.lastChange = 0
   }
 
   /**
-   * Undo the last locally created change.
+   * Undo last changes on type.
    *
-   * @private
-   * @function
+   * @return {StackItem?} Returns StackItem if a change was applied
    */
   undo () {
-    this._undoing = true
-    const performedUndo = applyReverseOperation(this.y, this._scope, this._undoBuffer)
-    this._undoing = false
-    return performedUndo
+    this.undoing = true
+    let res
+    try {
+      res = popStackItem(this, this.undoStack, 'undo')
+    } finally {
+      this.undoing = false
+    }
+    return res
   }
 
   /**
-   * Redo the last locally created change.
+   * Redo last undo operation.
    *
-   * @private
-   * @function
+   * @return {StackItem?} Returns StackItem if a change was applied
    */
   redo () {
-    this._redoing = true
-    const performedRedo = applyReverseOperation(this.y, this._scope, this._redoBuffer)
-    this._redoing = false
-    return performedRedo
+    this.redoing = true
+    let res
+    try {
+      res = popStackItem(this, this.redoStack, 'redo')
+    } finally {
+      this.redoing = false
+    }
+    return res
   }
 }

src/utils/YEvent.js

@@ -1,9 +1,12 @@
 
 import {
   isDeleted,
-  AbstractType, Transaction, AbstractStruct // eslint-disable-line
+  Item, AbstractType, Transaction, AbstractStruct // eslint-disable-line
 } from '../internals.js'
 
+import * as set from 'lib0/set.js'
+import * as array from 'lib0/array.js'
+
 /**
  * YEvent describes the changes on a YType.
  */
@@ -28,6 +31,10 @@ export class YEvent {
      * @type {Transaction}
      */
     this.transaction = transaction
+    /**
+     * @type {Object|null}
+     */
+    this._changes = null
   }
 
   /**
@@ -49,6 +56,8 @@ export class YEvent {
   /**
    * Check if a struct is deleted by this event.
    *
+   * In contrast to change.deleted, this method also returns true if the struct was added and then deleted.
+   *
    * @param {AbstractStruct} struct
    * @return {boolean}
    */
@@ -59,12 +68,121 @@ export class YEvent {
   /**
    * Check if a struct is added by this event.
    *
+   * In contrast to change.deleted, this method also returns true if the struct was added and then deleted.
+   *
    * @param {AbstractStruct} struct
    * @return {boolean}
    */
   adds (struct) {
     return struct.id.clock >= (this.transaction.beforeState.get(struct.id.client) || 0)
   }
+
+  /**
+   * @return {{added:Set<Item>,deleted:Set<Item>,delta:Array<{insert:Array<any>}|{delete:number}|{retain:number}>}}
+   */
+  get changes () {
+    let changes = this._changes
+    if (changes === null) {
+      const target = this.target
+      const added = set.create()
+      const deleted = set.create()
+      /**
+       * @type {Array<{insert:Array<any>}|{delete:number}|{retain:number}>}
+       */
+      const delta = []
+      /**
+       * @type {Map<string,{ action: 'add' | 'update' | 'delete', oldValue: any}>}
+       */
+      const keys = new Map()
+      changes = {
+        added, deleted, delta, keys
+      }
+      const changed = /** @type Set<string|null> */ (this.transaction.changed.get(target))
+      if (changed.has(null)) {
+        /**
+         * @type {any}
+         */
+        let lastOp = null
+        const packOp = () => {
+          if (lastOp) {
+            delta.push(lastOp)
+          }
+        }
+        for (let item = target._start; item !== null; item = item.right) {
+          if (item.deleted) {
+            if (this.deletes(item) && !this.adds(item)) {
+              if (lastOp === null || lastOp.delete === undefined) {
+                packOp()
+                lastOp = { delete: 0 }
+              }
+              lastOp.delete += item.length
+              deleted.add(item)
+            } // else nop
+          } else {
+            if (this.adds(item)) {
+              if (lastOp === null || lastOp.insert === undefined) {
+                packOp()
+                lastOp = { insert: [] }
+              }
+              lastOp.insert = lastOp.insert.concat(item.content.getContent())
+              added.add(item)
+            } else {
+              if (lastOp === null || lastOp.retain === undefined) {
+                packOp()
+                lastOp = { retain: 0 }
+              }
+              lastOp.retain += item.length
+            }
+          }
+        }
+        if (lastOp !== null && lastOp.retain === undefined) {
+          packOp()
+        }
+      }
+      changed.forEach(key => {
+        if (key !== null) {
+          const item = /** @type {Item} */ (target._map.get(key))
+          /**
+           * @type {'delete' | 'add' | 'update'}
+           */
+          let action
+          let oldValue
+          if (this.adds(item)) {
+            let prev = item.left
+            while (prev !== null && this.adds(prev)) {
+              prev = prev.left
+            }
+            if (this.deletes(item)) {
+              if (prev !== null && this.deletes(prev)) {
+                action = 'delete'
+                oldValue = array.last(prev.content.getContent())
+              } else {
+                return
+              }
+            } else {
+              if (prev !== null && this.deletes(prev)) {
+                action = 'update'
+                oldValue = array.last(prev.content.getContent())
+              } else {
+                action = 'add'
+                oldValue = undefined
+              }
+            }
+          } else {
+            if (this.deletes(item)) {
+              action = 'delete'
+              oldValue = array.last(/** @type {Item} */ item.content.getContent())
+            } else {
+              return // nop
+            }
+          }
+          keys.set(key, { action, oldValue })
+        }
+      })
+      this._changes = changes
+    }
+    return changes
+  }
 }
 
 /**

src/utils/cursor.js

@@ -1,266 +0,0 @@
-/**
- * @module Cursors
- */
-
-import {
-  getItem,
-  getItemType,
-  createID,
-  writeID,
-  readID,
-  compareIDs,
-  getState,
-  findRootTypeKey,
-  AbstractItem,
-  ID, StructStore, Y, AbstractType // eslint-disable-line
-} from '../internals.js'
-
-import * as encoding from 'lib0/encoding.js'
-import * as decoding from 'lib0/decoding.js'
-import * as error from 'lib0/error.js'
-
-/**
- * A Cursor is a relative position that is based on the Yjs model. In contrast to an
- * absolute position (position by index), the Cursor can be
- * recomputed when remote changes are received. For example:
- *
- * ```Insert(0, 'x')('a|bc') = 'xa|bc'``` Where | is the cursor position.
- *
- * A relative cursor position can be obtained with the function
- *
- * One of the properties must be defined.
- *
- * @example
- *   // Current cursor position is at position 10
- *   const relativePosition = createCursorFromOffset(yText, 10)
- *   // modify yText
- *   yText.insert(0, 'abc')
- *   yText.delete(3, 10)
- *   // Compute the cursor position
- *   const absolutePosition = toAbsolutePosition(y, relativePosition)
- *   absolutePosition.type === yText // => true
- *   console.log('cursor location is ' + absolutePosition.offset) // => cursor location is 3
- *
- */
-export class Cursor {
-  /**
-   * @param {ID|null} type
-   * @param {string|null} tname
-   * @param {ID|null} item
-   */
-  constructor (type, tname, item) {
-    /**
-     * @type {ID|null}
-     */
-    this.type = type
-    /**
-     * @type {string|null}
-     */
-    this.tname = tname
-    /**
-     * @type {ID | null}
-     */
-    this.item = item
-  }
-  toJSON () {
-    const json = {}
-    if (this.type !== null) {
-      json.type = this.type.toJSON()
-    }
-    if (this.tname !== null) {
-      json.tname = this.tname
-    }
-    if (this.item !== null) {
-      json.item = this.item.toJSON()
-    }
-    return json
-  }
-}
-
-/**
- * @param {Object} json
- * @return {Cursor}
- *
- * @function
- */
-export const createCursorFromJSON = json => new Cursor(json.type == null ? null : createID(json.type.client, json.type.clock), json.tname || null, json.item == null ? null : createID(json.item.client, json.item.clock))
-
-export class AbsolutePosition {
-  /**
-   * @param {AbstractType<any>} type
-   * @param {number} offset
-   */
-  constructor (type, offset) {
-    /**
-     * @type {AbstractType<any>}
-     */
-    this.type = type
-    /**
-     * @type {number}
-     */
-    this.offset = offset
-  }
-}
-
-/**
- * @param {AbstractType<any>} type
- * @param {number} offset
- *
- * @function
- */
-export const createAbsolutePosition = (type, offset) => new AbsolutePosition(type, offset)
-
-/**
- * @param {AbstractType<any>} type
- * @param {ID|null} item
- *
- * @function
- */
-export const createCursor = (type, item) => {
-  let typeid = null
-  let tname = null
-  if (type._item === null) {
-    tname = findRootTypeKey(type)
-  } else {
-    typeid = type._item.id
-  }
-  return new Cursor(typeid, tname, item)
-}
-
-/**
- * Create a relativePosition based on a absolute position.
- *
- * @param {AbstractType<any>} type The base type (e.g. YText or YArray).
- * @param {number} offset The absolute position.
- * @return {Cursor}
- *
- * @function
- */
-export const createCursorFromTypeOffset = (type, offset) => {
-  let t = type._start
-  while (t !== null) {
-    if (!t.deleted && t.countable) {
-      if (t.length > offset) {
-        // case 1: found position somewhere in the linked list
-        return createCursor(type, createID(t.id.client, t.id.clock + offset))
-      }
-      offset -= t.length
-    }
-    t = t.right
-  }
-  return createCursor(type, null)
-}
-
-/**
- * @param {encoding.Encoder} encoder
- * @param {Cursor} rpos
- *
- * @function
- */
-export const writeCursor = (encoder, rpos) => {
-  const { type, tname, item } = rpos
-  if (item !== null) {
-    encoding.writeVarUint(encoder, 0)
-    writeID(encoder, item)
-  } else if (tname !== null) {
-    // case 2: found position at the end of the list and type is stored in y.share
-    encoding.writeUint8(encoder, 1)
-    encoding.writeVarString(encoder, tname)
-  } else if (type !== null) {
-    // case 3: found position at the end of the list and type is attached to an item
-    encoding.writeUint8(encoder, 2)
-    writeID(encoder, type)
-  } else {
-    throw error.unexpectedCase()
-  }
-  return encoder
-}
-
-/**
- * @param {decoding.Decoder} decoder
- * @param {Y} y
- * @param {StructStore} store
- * @return {Cursor|null}
- *
- * @function
- */
-export const readCursor = (decoder, y, store) => {
-  let type = null
-  let tname = null
-  let itemID = null
-  switch (decoding.readVarUint(decoder)) {
-    case 0:
-      // case 1: found position somewhere in the linked list
-      itemID = readID(decoder)
-      break
-    case 1:
-      // case 2: found position at the end of the list and type is stored in y.share
-      tname = decoding.readVarString(decoder)
-      break
-    case 2: {
-      // case 3: found position at the end of the list and type is attached to an item
-      type = readID(decoder)
-    }
-  }
-  return new Cursor(type, tname, itemID)
-}
-
-/**
- * @param {Cursor} cursor
- * @param {Y} y
- * @return {AbsolutePosition|null}
- *
- * @function
- */
-export const createAbsolutePositionFromCursor = (cursor, y) => {
-  const store = y.store
-  const rightID = cursor.item
-  const typeID = cursor.type
-  const tname = cursor.tname
-  let type = null
-  let offset = 0
-  if (rightID !== null) {
-    if (getState(store, rightID.client) <= rightID.clock) {
-      return null
-    }
-    const right = getItem(store, rightID)
-    if (!(right instanceof AbstractItem)) {
-      return null
-    }
-    offset = right.deleted || !right.countable ? 0 : rightID.clock - right.id.clock
-    let n = right.left
-    while (n !== null) {
-      if (!n.deleted && n.countable) {
-        offset += n.length
-      }
-      n = n.left
-    }
-    type = right.parent
-  } else {
-    if (tname !== null) {
-      type = y.get(tname)
-    } else if (typeID !== null) {
-      type = getItemType(store, typeID).type
-    } else {
-      throw error.unexpectedCase()
-    }
-    offset = type._length
-  }
-  if (type._item !== null && type._item.deleted) {
-    return null
-  }
-  return createAbsolutePosition(type, offset)
-}
-
-/**
- * @param {Cursor|null} a
- * @param {Cursor|null} b
- *
- * @function
- */
-export const compareCursors = (a, b) => a === b || (
-  a !== null && b !== null && a.tname === b.tname && (
-    (a.item !== null && b.item !== null && compareIDs(a.item, b.item)) ||
-    (a.type !== null && b.type !== null && compareIDs(a.type, b.type))
-  )
-)

src/utils/encoding.js

@@ -1,47 +1,39 @@
 
 /**
  * @module encoding
+ *
+ * We use the first five bits in the info flag for determining the type of the struct.
+ *
+ * 0: GC
+ * 1: Item with Deleted content
+ * 2: Item with JSON content
+ * 3: Item with Binary content
+ * 4: Item with String content
+ * 5: Item with Embed content (for richtext content)
+ * 6: Item with Format content (a formatting marker for richtext content)
+ * 7: Item with Type
  */
 
 import {
   findIndexSS,
   GCRef,
-  ItemBinaryRef,
-  ItemDeletedRef,
-  ItemEmbedRef,
-  ItemFormatRef,
-  ItemJSONRef,
-  ItemStringRef,
-  ItemTypeRef,
+  ItemRef,
   writeID,
   createID,
   readID,
   getState,
-  getStates,
-  readDeleteSet,
+  getStateVector,
+  readAndApplyDeleteSet,
   writeDeleteSet,
   createDeleteSetFromStructStore,
-  Transaction, AbstractStruct, AbstractStructRef, StructStore, ID // eslint-disable-line
+  transact,
+  Doc, Transaction, AbstractStruct, StructStore, ID // eslint-disable-line
 } from '../internals.js'
 
 import * as encoding from 'lib0/encoding.js'
 import * as decoding from 'lib0/decoding.js'
 import * as binary from 'lib0/binary.js'
 
-/**
- * @private
- */
-export const structRefs = [
-  GCRef,
-  ItemBinaryRef,
-  ItemDeletedRef,
-  ItemEmbedRef,
-  ItemFormatRef,
-  ItemJSONRef,
-  ItemStringRef,
-  ItemTypeRef
-]
-
 /**
  * @param {encoding.Encoder} encoder
  * @param {Array<AbstractStruct>} structs All structs by `client`
@@ -68,19 +60,19 @@ const writeStructs = (encoder, structs, client, clock) => {
  * @param {decoding.Decoder} decoder
  * @param {number} numOfStructs
  * @param {ID} nextID
- * @return {Array<AbstractStructRef>}
+ * @return {Array<GCRef|ItemRef>}
  *
  * @private
  * @function
  */
 const readStructRefs = (decoder, numOfStructs, nextID) => {
   /**
-   * @type {Array<AbstractStructRef>}
+   * @type {Array<GCRef|ItemRef>}
    */
   const refs = []
   for (let i = 0; i < numOfStructs; i++) {
     const info = decoding.readUint8(decoder)
-    const ref = new structRefs[binary.BITS5 & info](decoder, nextID, info)
+    const ref = (binary.BITS5 & info) === 0 ? new GCRef(decoder, nextID, info) : new ItemRef(decoder, nextID, info)
     nextID = createID(nextID.client, nextID.clock + ref.length)
     refs.push(ref)
   }
@@ -104,7 +96,7 @@ export const writeClientsStructs = (encoder, store, _sm) => {
       sm.set(client, clock)
     }
   })
-  getStates(store).forEach((clock, client) => {
+  getStateVector(store).forEach((clock, client) => {
     if (!_sm.has(client)) {
       sm.set(client, 0)
     }
@@ -119,14 +111,14 @@ export const writeClientsStructs = (encoder, store, _sm) => {
 
 /**
  * @param {decoding.Decoder} decoder The decoder object to read data from.
- * @return {Map<number,Array<AbstractStructRef>>}
+ * @return {Map<number,Array<GCRef|ItemRef>>}
  *
  * @private
  * @function
  */
 export const readClientsStructRefs = decoder => {
   /**
-   * @type {Map<number,Array<AbstractStructRef>>}
+   * @type {Map<number,Array<GCRef|ItemRef>>}
    */
   const clientRefs = new Map()
   const numOfStateUpdates = decoding.readVarUint(decoder)
@@ -193,7 +185,7 @@ const resumeStructIntegration = (transaction, store) => {
           structRefs.refs[structRefs.i] = ref
           stack[stack.length - 1] = r
           // sort the set because this approach might bring the list out of order
-          structRefs.refs = structRefs.refs.slice(structRefs.i).sort((r1, r2) => r1.id.client - r2.id.client)
+          structRefs.refs = structRefs.refs.slice(structRefs.i).sort((r1, r2) => r1.id.clock - r2.id.clock)
           structRefs.i = 0
           continue
         }
@@ -239,7 +231,7 @@ export const tryResumePendingDeleteReaders = (transaction, store) => {
   const pendingReaders = store.pendingDeleteReaders
   store.pendingDeleteReaders = []
   for (let i = 0; i < pendingReaders.length; i++) {
-    readDeleteSet(pendingReaders[i], transaction, store)
+    readAndApplyDeleteSet(pendingReaders[i], transaction, store)
   }
 }
 
@@ -250,11 +242,11 @@ export const tryResumePendingDeleteReaders = (transaction, store) => {
  * @private
  * @function
  */
-export const writeStructsFromTransaction = (encoder, transaction) => writeClientsStructs(encoder, transaction.y.store, transaction.beforeState)
+export const writeStructsFromTransaction = (encoder, transaction) => writeClientsStructs(encoder, transaction.doc.store, transaction.beforeState)
 
 /**
  * @param {StructStore} store
- * @param {Map<number, Array<AbstractStructRef>>} clientsStructsRefs
+ * @param {Map<number, Array<GCRef|ItemRef>>} clientsStructsRefs
  *
  * @private
  * @function
@@ -297,25 +289,135 @@ export const readStructs = (decoder, transaction, store) => {
 }
 
 /**
+ * Read and apply a document update.
+ *
+ * This function has the same effect as `applyUpdate` but accepts an decoder.
+ *
  * @param {decoding.Decoder} decoder
- * @param {Transaction} transaction
- * @param {StructStore} store
+ * @param {Doc} ydoc
+ * @param {any} [transactionOrigin] This will be stored on `transaction.origin` and `.on('update', (update, origin))`
  *
  * @function
  */
-export const readModel = (decoder, transaction, store) => {
-  readStructs(decoder, transaction, store)
-  readDeleteSet(decoder, transaction, store)
+export const readUpdate = (decoder, ydoc, transactionOrigin) =>
+  transact(ydoc, transaction => {
+    readStructs(decoder, transaction, ydoc.store)
+    readAndApplyDeleteSet(decoder, transaction, ydoc.store)
+  }, transactionOrigin, false)
+
+/**
+ * Apply a document update created by, for example, `y.on('update', update => ..)` or `update = encodeStateAsUpdate()`.
+ *
+ * This function has the same effect as `readUpdate` but accepts an Uint8Array instead of a Decoder.
+ *
+ * @param {Doc} ydoc
+ * @param {Uint8Array} update
+ * @param {any} [transactionOrigin] This will be stored on `transaction.origin` and `.on('update', (update, origin))`
+ *
+ * @function
+ */
+export const applyUpdate = (ydoc, update, transactionOrigin) =>
+  readUpdate(decoding.createDecoder(update), ydoc, transactionOrigin)
+
+/**
+ * Write all the document as a single update message. If you specify the state of the remote client (`targetStateVector`) it will
+ * only write the operations that are missing.
+ *
+ * @param {encoding.Encoder} encoder
+ * @param {Doc} doc
+ * @param {Map<number,number>} [targetStateVector] The state of the target that receives the update. Leave empty to write all known structs
+ *
+ * @function
+ */
+export const writeStateAsUpdate = (encoder, doc, targetStateVector = new Map()) => {
+  writeClientsStructs(encoder, doc.store, targetStateVector)
+  writeDeleteSet(encoder, createDeleteSetFromStructStore(doc.store))
 }
 
 /**
- * @param {encoding.Encoder} encoder
- * @param {StructStore} store
- * @param {Map<number,number>} [targetState] The state of the target that receives the update. Leave empty to write all known structs
+ * Write all the document as a single update message that can be applied on the remote document. If you specify the state of the remote client (`targetState`) it will
+ * only write the operations that are missing.
+ *
+ * Use `writeStateAsUpdate` instead if you are working with lib0/encoding.js#Encoder
+ *
+ * @param {Doc} doc
+ * @param {Uint8Array} [encodedTargetStateVector] The state of the target that receives the update. Leave empty to write all known structs
+ * @return {Uint8Array}
  *
  * @function
  */
-export const writeModel = (encoder, store, targetState = new Map()) => {
-  writeClientsStructs(encoder, store, targetState)
-  writeDeleteSet(encoder, createDeleteSetFromStructStore(store))
+export const encodeStateAsUpdate = (doc, encodedTargetStateVector) => {
+  const encoder = encoding.createEncoder()
+  const targetStateVector = encodedTargetStateVector == null ? new Map() : decodeStateVector(encodedTargetStateVector)
+  writeStateAsUpdate(encoder, doc, targetStateVector)
+  return encoding.toUint8Array(encoder)
+}
+
+/**
+ * Read state vector from Decoder and return as Map
+ *
+ * @param {decoding.Decoder} decoder
+ * @return {Map<number,number>} Maps `client` to the number next expected `clock` from that client.
+ *
+ * @function
+ */
+export const readStateVector = decoder => {
+  const ss = new Map()
+  const ssLength = decoding.readVarUint(decoder)
+  for (let i = 0; i < ssLength; i++) {
+    const client = decoding.readVarUint(decoder)
+    const clock = decoding.readVarUint(decoder)
+    ss.set(client, clock)
+  }
+  return ss
+}
+
+/**
+ * Read decodedState and return State as Map.
+ *
+ * @param {Uint8Array} decodedState
+ * @return {Map<number,number>} Maps `client` to the number next expected `clock` from that client.
+ *
+ * @function
+ */
+export const decodeStateVector = decodedState => readStateVector(decoding.createDecoder(decodedState))
+
+/**
+ * Write State Vector to `lib0/encoding.js#Encoder`.
+ *
+ * @param {encoding.Encoder} encoder
+ * @param {Map<number,number>} sv
+ * @function
+ */
+export const writeStateVector = (encoder, sv) => {
+  encoding.writeVarUint(encoder, sv.size)
+  sv.forEach((clock, client) => {
+    encoding.writeVarUint(encoder, client)
+    encoding.writeVarUint(encoder, clock)
+  })
+  return encoder
+}
+
+/**
+ * Write State Vector to `lib0/encoding.js#Encoder`.
+ *
+ * @param {encoding.Encoder} encoder
+ * @param {Doc} doc
+ *
+ * @function
+ */
+export const writeDocumentStateVector = (encoder, doc) => writeStateVector(encoder, getStateVector(doc.store))
+
+/**
+ * Encode State as Uint8Array.
+ *
+ * @param {Doc} doc
+ * @return {Uint8Array}
+ *
+ * @function
+ */
+export const encodeStateVector = doc => {
+  const encoder = encoding.createEncoder()
+  writeDocumentStateVector(encoder, doc)
+  return encoding.toUint8Array(encoder)
 }

src/utils/isParentOf.js

@@ -1,22 +1,22 @@
 
-import { AbstractType } from '../internals.js' // eslint-disable-line
+import { AbstractType, Item } from '../internals.js' // eslint-disable-line
 
 /**
  * Check if `parent` is a parent of `child`.
  *
  * @param {AbstractType<any>} parent
- * @param {AbstractType<any>} child
+ * @param {Item|null} child
  * @return {Boolean} Whether `parent` is a parent of `child`.
  *
  * @private
  * @function
  */
 export const isParentOf = (parent, child) => {
-  while (child._item !== null) {
-    if (child === parent) {
+  while (child !== null) {
+    if (child.parent === parent) {
       return true
     }
-    child = child._item.parent
+    child = child.parent._item
   }
   return false
 }

tests/encoding.tests.js

@@ -1,36 +1,28 @@
 import * as t from 'lib0/testing.js'
 
 import {
-  structRefs,
-  structGCRefNumber,
-  structBinaryRefNumber,
-  structDeletedRefNumber,
-  structEmbedRefNumber,
-  structFormatRefNumber,
-  structJSONRefNumber,
-  structStringRefNumber,
-  structTypeRefNumber,
-  GCRef,
-  ItemBinaryRef,
-  ItemDeletedRef,
-  ItemEmbedRef,
-  ItemFormatRef,
-  ItemJSONRef,
-  ItemStringRef,
-  ItemTypeRef
+  contentRefs,
+  readContentBinary,
+  readContentDeleted,
+  readContentString,
+  readContentJSON,
+  readContentEmbed,
+  readContentType,
+  readContentFormat,
+  readContentAny
 } from '../src/internals.js'
 
 /**
  * @param {t.TestCase} tc
  */
 export const testStructReferences = tc => {
-  t.assert(structRefs.length === 8)
-  t.assert(structRefs[structGCRefNumber] === GCRef)
-  t.assert(structRefs[structBinaryRefNumber] === ItemBinaryRef)
-  t.assert(structRefs[structDeletedRefNumber] === ItemDeletedRef)
-  t.assert(structRefs[structEmbedRefNumber] === ItemEmbedRef)
-  t.assert(structRefs[structFormatRefNumber] === ItemFormatRef)
-  t.assert(structRefs[structJSONRefNumber] === ItemJSONRef)
-  t.assert(structRefs[structStringRefNumber] === ItemStringRef)
-  t.assert(structRefs[structTypeRefNumber] === ItemTypeRef)
+  t.assert(contentRefs.length === 9)
+  t.assert(contentRefs[1] === readContentDeleted)
+  t.assert(contentRefs[2] === readContentJSON) // TODO: deprecate content json?
+  t.assert(contentRefs[3] === readContentBinary)
+  t.assert(contentRefs[4] === readContentString)
+  t.assert(contentRefs[5] === readContentEmbed)
+  t.assert(contentRefs[6] === readContentFormat)
+  t.assert(contentRefs[7] === readContentType)
+  t.assert(contentRefs[8] === readContentAny)
 }

tests/index.js

@@ -4,6 +4,7 @@ import * as map from './y-map.tests.js'
 import * as text from './y-text.tests.js'
 import * as xml from './y-xml.tests.js'
 import * as encoding from './encoding.tests.js'
+import * as undoredo from './undo-redo.tests.js'
 
 import { runTests } from 'lib0/testing.js'
 import { isBrowser, isNode } from 'lib0/environment.js'
@@ -13,7 +14,7 @@ if (isBrowser) {
   log.createVConsole(document.body)
 }
 runTests({
-  map, array, text, xml, encoding
+  map, array, text, xml, encoding, undoredo
 }).then(success => {
   /* istanbul ignore next */
   if (isNode) {

tests/testHelper.js

@@ -2,36 +2,21 @@ import * as Y from '../src/index.js'
 
 import {
   createDeleteSetFromStructStore,
-  getStates,
-  AbstractItem,
-  DeleteSet, StructStore // eslint-disable-line
+  getStateVector,
+  Item,
+  DeleteItem, DeleteSet, StructStore, Doc // eslint-disable-line
 } from '../src/internals.js'
 
 import * as t from 'lib0/testing.js'
 import * as prng from 'lib0/prng.js'
-import { createMutex } from 'lib0/mutex.js'
 import * as encoding from 'lib0/encoding.js'
 import * as decoding from 'lib0/decoding.js'
 import * as syncProtocol from 'y-protocols/sync.js'
-
-/**
- * @param {TestYInstance} y
- * @param {Y.Transaction} transaction
- */
-const afterTransaction = (y, transaction) => {
-  y.mMux(() => {
-    const m = transaction.updateMessage
-    if (m !== null) {
-      const encoder = encoding.createEncoder()
-      syncProtocol.writeUpdate(encoder, m)
-      broadcastMessage(y, encoding.toBuffer(encoder))
-    }
-  })
-}
+export * from '../src/internals.js'
 
 /**
  * @param {TestYInstance} y // publish message created by `y` to all other online clients
- * @param {ArrayBuffer} m
+ * @param {Uint8Array} m
  */
 const broadcastMessage = (y, m) => {
   if (y.tc.onlineConns.has(y)) {
@@ -43,7 +28,7 @@ const broadcastMessage = (y, m) => {
   }
 }
 
-export class TestYInstance extends Y.Y {
+export class TestYInstance extends Doc {
   /**
    * @param {TestConnector} testConnector
    * @param {number} clientID
@@ -56,17 +41,18 @@ export class TestYInstance extends Y.Y {
      */
     this.tc = testConnector
     /**
-     * @type {Map<TestYInstance, Array<ArrayBuffer>>}
+     * @type {Map<TestYInstance, Array<Uint8Array>>}
      */
     this.receiving = new Map()
-    /**
-     * Message mutex
-     * @type {Function}
-     */
-    this.mMux = createMutex()
     testConnector.allConns.add(this)
     // set up observe on local model
-    this.on('afterTransactionCleanup', afterTransaction)
+    this.on('update', /** @param {Uint8Array} update @param {any} origin */ (update, origin) => {
+      if (origin !== testConnector) {
+        const encoder = encoding.createEncoder()
+        syncProtocol.writeUpdate(encoder, update)
+        broadcastMessage(this, encoding.toUint8Array(encoder))
+      }
+    })
     this.connect()
   }
   /**
@@ -84,15 +70,15 @@ export class TestYInstance extends Y.Y {
     if (!this.tc.onlineConns.has(this)) {
       this.tc.onlineConns.add(this)
       const encoder = encoding.createEncoder()
-      syncProtocol.writeSyncStep1(encoder, this.store)
+      syncProtocol.writeSyncStep1(encoder, this)
       // publish SyncStep1
-      broadcastMessage(this, encoding.toBuffer(encoder))
+      broadcastMessage(this, encoding.toUint8Array(encoder))
       this.tc.onlineConns.forEach(remoteYInstance => {
         if (remoteYInstance !== this) {
           // remote instance sends instance to this instance
           const encoder = encoding.createEncoder()
-          syncProtocol.writeSyncStep1(encoder, remoteYInstance.store)
-          this._receive(encoding.toBuffer(encoder), remoteYInstance)
+          syncProtocol.writeSyncStep1(encoder, remoteYInstance)
+          this._receive(encoding.toUint8Array(encoder), remoteYInstance)
         }
       })
     }
@@ -101,7 +87,7 @@ export class TestYInstance extends Y.Y {
    * Receive a message from another client. This message is only appended to the list of receiving messages.
    * TestConnector decides when this client actually reads this message.
    *
-   * @param {ArrayBuffer} message
+   * @param {Uint8Array} message
    * @param {TestYInstance} remoteClient
    */
   _receive (message, remoteClient) {
@@ -165,14 +151,12 @@ export class TestConnector {
         return this.flushRandomMessage()
       }
       const encoder = encoding.createEncoder()
-      receiver.mMux(() => {
-        // console.log('receive (' + sender.userID + '->' + receiver.userID + '):\n', syncProtocol.stringifySyncMessage(decoding.createDecoder(m), receiver))
-        // do not publish data created when this function is executed (could be ss2 or update message)
-        syncProtocol.readSyncMessage(decoding.createDecoder(m), encoder, receiver)
-      })
+      // console.log('receive (' + sender.userID + '->' + receiver.userID + '):\n', syncProtocol.stringifySyncMessage(decoding.createDecoder(m), receiver))
+      // do not publish data created when this function is executed (could be ss2 or update message)
+      syncProtocol.readSyncMessage(decoding.createDecoder(m), encoder, receiver, receiver.tc)
       if (encoding.length(encoder) > 0) {
         // send reply message
-        sender._receive(encoding.toBuffer(encoder), receiver)
+        sender._receive(encoding.toUint8Array(encoder), receiver)
       }
       return true
     }
@@ -230,11 +214,13 @@ export class TestConnector {
 }
 
 /**
+ * @template T
  * @param {t.TestCase} tc
  * @param {{users?:number}} conf
- * @return {{testConnector:TestConnector,users:Array<TestYInstance>,array0:Y.Array<any>,array1:Y.Array<any>,array2:Y.Array<any>,map0:Y.Map<any>,map1:Y.Map<any>,map2:Y.Map<any>,map3:Y.Map<any>,text0:Y.Text,text1:Y.Text,text2:Y.Text,xml0:Y.XmlElement,xml1:Y.XmlElement,xml2:Y.XmlElement}}
+ * @param {InitTestObjectCallback<T>} [initTestObject]
+ * @return {{testObjects:Array<any>,testConnector:TestConnector,users:Array<TestYInstance>,array0:Y.Array<any>,array1:Y.Array<any>,array2:Y.Array<any>,map0:Y.Map<any>,map1:Y.Map<any>,map2:Y.Map<any>,map3:Y.Map<any>,text0:Y.Text,text1:Y.Text,text2:Y.Text,xml0:Y.XmlElement,xml1:Y.XmlElement,xml2:Y.XmlElement}}
  */
-export const init = (tc, { users = 5 } = {}) => {
+export const init = (tc, { users = 5 } = {}, initTestObject) => {
   /**
    * @type {Object<string,any>}
    */
@@ -254,8 +240,8 @@ export const init = (tc, { users = 5 } = {}) => {
     result['text' + i] = y.get('text', Y.Text)
   }
   testConnector.syncAll()
-  // @ts-ignore
-  return result
+  result.testObjects = result.users.map(initTestObject || (() => null))
+  return /** @type {any} */ (result)
 }
 
 /**
@@ -270,7 +256,7 @@ export const init = (tc, { users = 5 } = {}) => {
 export const compare = users => {
   users.forEach(u => u.connect())
   while (users[0].tc.flushAllMessages()) {}
-  const userArrayValues = users.map(u => u.getArray('array').toJSON().map(val => JSON.stringify(val)))
+  const userArrayValues = users.map(u => u.getArray('array').toJSON())
   const userMapValues = users.map(u => u.getMap('map').toJSON())
   const userXmlValues = users.map(u => u.get('xml', Y.XmlElement).toString())
   const userTextValues = users.map(u => u.getText('text').toDelta())
@@ -279,15 +265,29 @@ export const compare = users => {
     t.assert(u.store.pendingStack.length === 0)
     t.assert(u.store.pendingClientsStructRefs.size === 0)
   }
+  // Test Array iterator
+  t.compare(users[0].getArray('array').toArray(), Array.from(users[0].getArray('array')))
+  // Test Map iterator
+  const ymapkeys = Array.from(users[0].getMap('map').keys())
+  t.assert(ymapkeys.length === Object.keys(userMapValues[0]).length)
+  ymapkeys.forEach(key => t.assert(userMapValues[0].hasOwnProperty(key)))
+  /**
+   * @type {Object<string,any>}
+   */
+  const mapRes = {}
+  for (let [k, v] of users[0].getMap('map')) {
+    mapRes[k] = v instanceof Y.AbstractType ? v.toJSON() : v
+  }
+  t.compare(userMapValues[0], mapRes)
+  // Compare all users
   for (let i = 0; i < users.length - 1; i++) {
     t.compare(userArrayValues[i].length, users[i].getArray('array').length)
     t.compare(userArrayValues[i], userArrayValues[i + 1])
     t.compare(userMapValues[i], userMapValues[i + 1])
     t.compare(userXmlValues[i], userXmlValues[i + 1])
-    // @ts-ignore
-    t.compare(userTextValues[i].map(a => a.insert).join('').length, users[i].getText('text').length)
+    t.compare(userTextValues[i].map(/** @param {any} a */ a => typeof a.insert === 'string' ? a.insert : ' ').join('').length, users[i].getText('text').length)
     t.compare(userTextValues[i], userTextValues[i + 1])
-    t.compare(getStates(users[i].store), getStates(users[i + 1].store))
+    t.compare(getStateVector(users[i].store), getStateVector(users[i + 1].store))
     compareDS(createDeleteSetFromStructStore(users[i].store), createDeleteSetFromStructStore(users[i + 1].store))
     compareStructStores(users[i].store, users[i + 1].store)
   }
@@ -295,8 +295,8 @@ export const compare = users => {
 }
 
 /**
- * @param {AbstractItem?} a
- * @param {AbstractItem?} b
+ * @param {Item?} a
+ * @param {Item?} b
  * @return {boolean}
  */
 export const compareItemIDs = (a, b) => a === b || (a !== null && b != null && Y.compareIDs(a.id, b.id))
@@ -308,11 +308,10 @@ export const compareItemIDs = (a, b) => a === b || (a !== null && b != null && Y
 export const compareStructStores = (ss1, ss2) => {
   t.assert(ss1.clients.size === ss2.clients.size)
   for (const [client, structs1] of ss1.clients) {
-    const structs2 = ss2.clients.get(client)
+    const structs2 = /** @type {Array<Y.AbstractStruct>} */ (ss2.clients.get(client))
     t.assert(structs2 !== undefined && structs1.length === structs2.length)
     for (let i = 0; i < structs1.length; i++) {
       const s1 = structs1[i]
-      // @ts-ignore
       const s2 = structs2[i]
       // checks for abstract struct
       if (
@@ -323,9 +322,9 @@ export const compareStructStores = (ss1, ss2) => {
       ) {
         t.fail('Structs dont match')
       }
-      if (s1 instanceof AbstractItem) {
+      if (s1 instanceof Item) {
         if (
-          !(s2 instanceof AbstractItem) ||
+          !(s2 instanceof Item) ||
           !((s1.left === null && s2.left === null) || (s1.left !== null && s2.left !== null && Y.compareIDs(s1.left.lastId, s2.left.lastId))) ||
           !compareItemIDs(s1.right, s2.right) ||
           !Y.compareIDs(s1.origin, s2.origin) ||
@@ -351,11 +350,10 @@ export const compareStructStores = (ss1, ss2) => {
 export const compareDS = (ds1, ds2) => {
   t.assert(ds1.clients.size === ds2.clients.size)
   for (const [client, deleteItems1] of ds1.clients) {
-    const deleteItems2 = ds2.clients.get(client)
+    const deleteItems2 = /** @type {Array<DeleteItem>} */ (ds2.clients.get(client))
     t.assert(deleteItems2 !== undefined && deleteItems1.length === deleteItems2.length)
     for (let i = 0; i < deleteItems1.length; i++) {
       const di1 = deleteItems1[i]
-      // @ts-ignore
       const di2 = deleteItems2[i]
       if (di1.clock !== di2.clock || di1.len !== di2.len) {
         t.fail('DeleteSets dont match')
@@ -365,15 +363,24 @@ export const compareDS = (ds1, ds2) => {
 }
 
 /**
- * @param {t.TestCase} tc
- * @param {Array<function(TestYInstance,prng.PRNG):void>} mods
- * @param {number} iterations
+ * @template T
+ * @callback InitTestObjectCallback
+ * @param {TestYInstance} y
+ * @return {T}
  */
-export const applyRandomTests = (tc, mods, iterations) => {
+
+/**
+ * @template T
+ * @param {t.TestCase} tc
+ * @param {Array<function(Y.Doc,prng.PRNG,T):void>} mods
+ * @param {number} iterations
+ * @param {InitTestObjectCallback<T>} [initTestObject]
+ */
+export const applyRandomTests = (tc, mods, iterations, initTestObject) => {
   const gen = tc.prng
-  const result = init(tc, { users: 5 })
+  const result = init(tc, { users: 5 }, initTestObject)
   const { testConnector, users } = result
-  for (var i = 0; i < iterations; i++) {
+  for (let i = 0; i < iterations; i++) {
     if (prng.int31(gen, 0, 100) <= 2) {
       // 2% chance to disconnect/reconnect a random user
       if (prng.bool(gen)) {
@@ -388,9 +395,9 @@ export const applyRandomTests = (tc, mods, iterations) => {
       // 50% chance to flush a random message
       testConnector.flushRandomMessage()
     }
-    let user = prng.oneOf(gen, users)
-    var test = prng.oneOf(gen, mods)
-    test(user, gen)
+    const user = prng.int31(gen, 0, users.length - 1)
+    const test = prng.oneOf(gen, mods)
+    test(users[user], gen, result.testObjects[user])
   }
   compare(users)
   return result

tests/undo-redo.tests.js

@@ -0,0 +1,248 @@
+import { init, compare, applyRandomTests, Doc } from './testHelper.js' // eslint-disable-line
+
+import {
+  UndoManager
+} from '../src/internals.js'
+
+import * as Y from '../src/index.js'
+import * as t from 'lib0/testing.js'
+
+/**
+ * @param {t.TestCase} tc
+ */
+export const testUndoText = tc => {
+  const { testConnector, text0, text1 } = init(tc, { users: 3 })
+  const undoManager = new UndoManager(text0)
+
+  // items that are added & deleted in the same transaction won't be undo
+  text0.insert(0, 'test')
+  text0.delete(0, 4)
+  undoManager.undo()
+  t.assert(text0.toString() === '')
+
+  // follow redone items
+  text0.insert(0, 'a')
+  undoManager.stopCapturing()
+  text0.delete(0, 1)
+  undoManager.stopCapturing()
+  undoManager.undo()
+  t.assert(text0.toString() === 'a')
+  undoManager.undo()
+  t.assert(text0.toString() === '')
+
+  text0.insert(0, 'abc')
+  text1.insert(0, 'xyz')
+  testConnector.syncAll()
+  undoManager.undo()
+  t.assert(text0.toString() === 'xyz')
+  undoManager.redo()
+  t.assert(text0.toString() === 'abcxyz')
+  testConnector.syncAll()
+  text1.delete(0, 1)
+  testConnector.syncAll()
+  undoManager.undo()
+  t.assert(text0.toString() === 'xyz')
+  undoManager.redo()
+  t.assert(text0.toString() === 'bcxyz')
+  // test marks
+  text0.format(1, 3, { bold: true })
+  t.compare(text0.toDelta(), [{ insert: 'b' }, { insert: 'cxy', attributes: { bold: true } }, { insert: 'z' }])
+  undoManager.undo()
+  t.compare(text0.toDelta(), [{ insert: 'bcxyz' }])
+  undoManager.redo()
+  t.compare(text0.toDelta(), [{ insert: 'b' }, { insert: 'cxy', attributes: { bold: true } }, { insert: 'z' }])
+}
+
+/**
+ * @param {t.TestCase} tc
+ */
+export const testUndoMap = tc => {
+  const { testConnector, map0, map1 } = init(tc, { users: 2 })
+  map0.set('a', 0)
+  const undoManager = new UndoManager(map0)
+  map0.set('a', 1)
+  undoManager.undo()
+  t.assert(map0.get('a') === 0)
+  undoManager.redo()
+  t.assert(map0.get('a') === 1)
+  // testing sub-types and if it can restore a whole type
+  const subType = new Y.Map()
+  map0.set('a', subType)
+  subType.set('x', 42)
+  t.compare(map0.toJSON(), /** @type {any} */ ({ 'a': { x: 42 } }))
+  undoManager.undo()
+  t.assert(map0.get('a') === 1)
+  undoManager.redo()
+  t.compare(map0.toJSON(), /** @type {any} */ ({ 'a': { x: 42 } }))
+  testConnector.syncAll()
+  // if content is overwritten by another user, undo operations should be skipped
+  map1.set('a', 44)
+  testConnector.syncAll()
+  undoManager.undo()
+  t.assert(map0.get('a') === 44)
+  undoManager.redo()
+  t.assert(map0.get('a') === 44)
+
+  // test setting value multiple times
+  map0.set('b', 'initial')
+  undoManager.stopCapturing()
+  map0.set('b', 'val1')
+  map0.set('b', 'val2')
+  undoManager.stopCapturing()
+  undoManager.undo()
+  t.assert(map0.get('b') === 'initial')
+}
+
+/**
+ * @param {t.TestCase} tc
+ */
+export const testUndoArray = tc => {
+  const { testConnector, array0, array1 } = init(tc, { users: 3 })
+  const undoManager = new UndoManager(array0)
+  array0.insert(0, [1, 2, 3])
+  array1.insert(0, [4, 5, 6])
+  testConnector.syncAll()
+  t.compare(array0.toArray(), [1, 2, 3, 4, 5, 6])
+  undoManager.undo()
+  t.compare(array0.toArray(), [4, 5, 6])
+  undoManager.redo()
+  t.compare(array0.toArray(), [1, 2, 3, 4, 5, 6])
+  testConnector.syncAll()
+  array1.delete(0, 1) // user1 deletes [1]
+  testConnector.syncAll()
+  undoManager.undo()
+  t.compare(array0.toArray(), [4, 5, 6])
+  undoManager.redo()
+  t.compare(array0.toArray(), [2, 3, 4, 5, 6])
+  array0.delete(0, 5)
+  // test nested structure
+  const ymap = new Y.Map()
+  array0.insert(0, [ymap])
+  t.compare(array0.toJSON(), [{}])
+  undoManager.stopCapturing()
+  ymap.set('a', 1)
+  t.compare(array0.toJSON(), [{ a: 1 }])
+  undoManager.undo()
+  t.compare(array0.toJSON(), [{}])
+  undoManager.undo()
+  t.compare(array0.toJSON(), [2, 3, 4, 5, 6])
+  undoManager.redo()
+  t.compare(array0.toJSON(), [{}])
+  undoManager.redo()
+  t.compare(array0.toJSON(), [{ a: 1 }])
+  testConnector.syncAll()
+  array1.get(0).set('b', 2)
+  testConnector.syncAll()
+  t.compare(array0.toJSON(), [{ a: 1, b: 2 }])
+  undoManager.undo()
+  t.compare(array0.toJSON(), [{ b: 2 }])
+  undoManager.undo()
+  t.compare(array0.toJSON(), [2, 3, 4, 5, 6])
+  undoManager.redo()
+  t.compare(array0.toJSON(), [{ b: 2 }])
+  undoManager.redo()
+  t.compare(array0.toJSON(), [{ a: 1, b: 2 }])
+}
+
+/**
+ * @param {t.TestCase} tc
+ */
+export const testUndoXml = tc => {
+  const { xml0 } = init(tc, { users: 3 })
+  const undoManager = new UndoManager(xml0)
+  const child = new Y.XmlElement('p')
+  xml0.insert(0, [child])
+  const textchild = new Y.XmlText('content')
+  child.insert(0, [textchild])
+  t.assert(xml0.toString() === '<undefined><p>content</p></undefined>')
+  // format textchild and revert that change
+  undoManager.stopCapturing()
+  textchild.format(3, 4, { bold: {} })
+  t.assert(xml0.toString() === '<undefined><p>con<bold>tent</bold></p></undefined>')
+  undoManager.undo()
+  t.assert(xml0.toString() === '<undefined><p>content</p></undefined>')
+  undoManager.redo()
+  t.assert(xml0.toString() === '<undefined><p>con<bold>tent</bold></p></undefined>')
+  xml0.delete(0, 1)
+  t.assert(xml0.toString() === '<undefined></undefined>')
+  undoManager.undo()
+  t.assert(xml0.toString() === '<undefined><p>con<bold>tent</bold></p></undefined>')
+}
+
+/**
+ * @param {t.TestCase} tc
+ */
+export const testUndoEvents = tc => {
+  const { text0 } = init(tc, { users: 3 })
+  const undoManager = new UndoManager(text0)
+  let counter = 0
+  let receivedMetadata = -1
+  undoManager.on('stack-item-added', /** @param {any} event */ event => {
+    t.assert(event.type != null)
+    event.stackItem.meta.set('test', counter++)
+  })
+  undoManager.on('stack-item-popped', /** @param {any} event */ event => {
+    t.assert(event.type != null)
+    receivedMetadata = event.stackItem.meta.get('test')
+  })
+  text0.insert(0, 'abc')
+  undoManager.undo()
+  t.assert(receivedMetadata === 0)
+  undoManager.redo()
+  t.assert(receivedMetadata === 1)
+}
+
+/**
+ * @param {t.TestCase} tc
+ */
+export const testTrackClass = tc => {
+  const { users, text0 } = init(tc, { users: 3 })
+  // only track origins that are numbers
+  const undoManager = new UndoManager(text0, { trackedOrigins: new Set([Number]) })
+  users[0].transact(() => {
+    text0.insert(0, 'abc')
+  }, 42)
+  t.assert(text0.toString() === 'abc')
+  undoManager.undo()
+  t.assert(text0.toString() === '')
+}
+
+/**
+ * @param {t.TestCase} tc
+ */
+export const testTypeScope = tc => {
+  const { array0 } = init(tc, { users: 3 })
+  // only track origins that are numbers
+  const text0 = new Y.Text()
+  const text1 = new Y.Text()
+  array0.insert(0, [text0, text1])
+  const undoManager = new UndoManager(text0)
+  const undoManagerBoth = new UndoManager([text0, text1])
+  text1.insert(0, 'abc')
+  t.assert(undoManager.undoStack.length === 0)
+  t.assert(undoManagerBoth.undoStack.length === 1)
+  t.assert(text1.toString() === 'abc')
+  undoManager.undo()
+  t.assert(text1.toString() === 'abc')
+  undoManagerBoth.undo()
+  t.assert(text1.toString() === '')
+}
+
+/**
+ * @param {t.TestCase} tc
+ */
+export const testUndoDeleteFilter = tc => {
+  /**
+   * @type {Array<Y.Map<any>>}
+   */
+  const array0 = /** @type {any} */ (init(tc, { users: 3 }).array0)
+  const undoManager = new UndoManager(array0, { deleteFilter: item => !(item instanceof Y.Item) || (item.content instanceof Y.ContentType && item.content.type._map.size === 0) })
+  const map0 = new Y.Map()
+  map0.set('hi', 1)
+  const map1 = new Y.Map()
+  array0.insert(0, [map0, map1])
+  undoManager.undo()
+  t.assert(array0.length === 1)
+  array0.get(0)
+  t.assert(Array.from(array0.get(0).keys()).length === 1)
+}

tests/y-array.tests.js

@@ -1,8 +1,9 @@
-import { init, compare, applyRandomTests, TestYInstance } from './testHelper.js' // eslint-disable-line
+import { init, compare, applyRandomTests, Doc } from './testHelper.js' // eslint-disable-line
 
 import * as Y from '../src/index.js'
 import * as t from 'lib0/testing.js'
 import * as prng from 'lib0/prng.js'
+import * as math from 'lib0/math.js'
 
 /**
  * @param {t.TestCase} tc
@@ -25,10 +26,10 @@ export const testDeleteInsert = tc => {
  */
 export const testInsertThreeElementsTryRegetProperty = tc => {
   const { testConnector, users, array0, array1 } = init(tc, { users: 2 })
-  array0.insert(0, [1, 2, 3])
-  t.compare(array0.toJSON(), [1, 2, 3], '.toJSON() works')
+  array0.insert(0, [1, true, false])
+  t.compare(array0.toJSON(), [1, true, false], '.toJSON() works')
   testConnector.flushAllMessages()
-  t.compare(array1.toJSON(), [1, 2, 3], '.toJSON() works after sync')
+  t.compare(array1.toJSON(), [1, true, false], '.toJSON() works after sync')
   compare(users)
 }
 
@@ -144,6 +145,32 @@ export const testInsertAndDeleteEvents = tc => {
   compare(users)
 }
 
+/**
+ * @param {t.TestCase} tc
+ */
+export const testNestedObserverEvents = tc => {
+  const { array0, users } = init(tc, { users: 2 })
+  /**
+   * @type {Array<number>}
+   */
+  const vals = []
+  array0.observe(e => {
+    if (array0.length === 1) {
+      // inserting, will call this observer again
+      // we expect that this observer is called after this event handler finishedn
+      array0.insert(1, [1])
+      vals.push(0)
+    } else {
+      // this should be called the second time an element is inserted (above case)
+      vals.push(1)
+    }
+  })
+  array0.insert(0, [0])
+  t.compareArrays(vals, [0, 1])
+  t.compareArrays(array0.toArray(), [0, 1])
+  compare(users)
+}
+
 /**
  * @param {t.TestCase} tc
  */
@@ -165,6 +192,33 @@ export const testInsertAndDeleteEventsForTypes = tc => {
   compare(users)
 }
 
+/**
+ * @param {t.TestCase} tc
+ */
+export const testChangeEvent = tc => {
+  const { array0, users } = init(tc, { users: 2 })
+  /**
+   * @type {any}
+   */
+  let changes = null
+  array0.observe(e => {
+    changes = e.changes
+  })
+  const newArr = new Y.Array()
+  array0.insert(0, [newArr, 4, 'dtrn'])
+  t.assert(changes !== null && changes.added.size === 2 && changes.deleted.size === 0)
+  t.compare(changes.delta, [{ insert: [newArr, 4, 'dtrn'] }])
+  changes = null
+  array0.delete(0, 2)
+  t.assert(changes !== null && changes.added.size === 0 && changes.deleted.size === 2)
+  t.compare(changes.delta, [{ delete: 2 }])
+  changes = null
+  array0.insert(1, [0.1])
+  t.assert(changes !== null && changes.added.size === 1 && changes.deleted.size === 0)
+  t.compare(changes.delta, [{ retain: 1 }, { insert: [0.1] }])
+  compare(users)
+}
+
 /**
  * @param {t.TestCase} tc
  */
@@ -184,6 +238,24 @@ export const testInsertAndDeleteEventsForTypes2 = tc => {
   compare(users)
 }
 
+/**
+ * This issue has been reported here https://github.com/yjs/yjs/issues/155
+ * @param {t.TestCase} tc
+ */
+export const testNewChildDoesNotEmitEventInTransaction = tc => {
+  const { array0, users } = init(tc, { users: 2 })
+  let fired = false
+  users[0].transact(() => {
+    const newMap = new Y.Map()
+    newMap.observe(() => {
+      fired = true
+    })
+    array0.insert(0, [newMap])
+    newMap.set('tst', 42)
+  })
+  t.assert(!fired, 'Event does not trigger')
+}
+
 /**
  * @param {t.TestCase} tc
  */
@@ -237,7 +309,7 @@ export const testEventTargetIsSetCorrectlyOnRemote = tc => {
  * @param {t.TestCase} tc
  */
 export const testIteratingArrayContainingTypes = tc => {
-  const y = new Y.Y()
+  const y = new Y.Doc()
   const arr = y.getArray('arr')
   const numItems = 10
   for (let i = 0; i < numItems; i++) {
@@ -256,7 +328,7 @@ let _uniqueNumber = 0
 const getUniqueNumber = () => _uniqueNumber++
 
 /**
- * @type {Array<function(TestYInstance,prng.PRNG):void>}
+ * @type {Array<function(Doc,prng.PRNG,any):void>}
  */
 const arrayTransactions = [
   function insert (user, gen) {
@@ -291,12 +363,12 @@ const arrayTransactions = [
     var length = yarray.length
     if (length > 0) {
       var somePos = prng.int31(gen, 0, length - 1)
-      var delLength = prng.int31(gen, 1, Math.min(2, length - somePos))
+      var delLength = prng.int31(gen, 1, math.min(2, length - somePos))
       if (prng.bool(gen)) {
         var type = yarray.get(somePos)
         if (type.length > 0) {
           somePos = prng.int31(gen, 0, type.length - 1)
-          delLength = prng.int31(gen, 0, Math.min(2, type.length - somePos))
+          delLength = prng.int31(gen, 0, math.min(2, type.length - somePos))
           type.delete(somePos, delLength)
         }
       } else {
@@ -309,8 +381,8 @@ const arrayTransactions = [
 /**
  * @param {t.TestCase} tc
  */
-export const testRepeatGeneratingYarrayTests20 = tc => {
-  applyRandomTests(tc, arrayTransactions, 3)
+export const testRepeatGeneratingYarrayTests4 = tc => {
+  applyRandomTests(tc, arrayTransactions, 4)
 }
 
 /**

tests/y-map.tests.js

@@ -1,4 +1,4 @@
-import { init, compare, applyRandomTests, TestYInstance } from './testHelper.js' // eslint-disable-line
+import { init, compare, applyRandomTests, Doc } from './testHelper.js' // eslint-disable-line
 
 import {
   compareIDs
@@ -19,6 +19,8 @@ export const testBasicMapTests = tc => {
   map0.set('string', 'hello Y')
   map0.set('object', { key: { key2: 'value' } })
   map0.set('y-map', new Y.Map())
+  map0.set('boolean1', true)
+  map0.set('boolean0', false)
   const map = map0.get('y-map')
   map.set('y-array', new Y.Array())
   const array = map.get('y-array')
@@ -27,6 +29,8 @@ export const testBasicMapTests = tc => {
 
   t.assert(map0.get('number') === 1, 'client 0 computed the change (number)')
   t.assert(map0.get('string') === 'hello Y', 'client 0 computed the change (string)')
+  t.assert(map0.get('boolean0') === false, 'client 0 computed the change (boolean)')
+  t.assert(map0.get('boolean1') === true, 'client 0 computed the change (boolean)')
   t.compare(map0.get('object'), { key: { key2: 'value' } }, 'client 0 computed the change (object)')
   t.assert(map0.get('y-map').get('y-array').get(0) === -1, 'client 0 computed the change (type)')
 
@@ -35,12 +39,16 @@ export const testBasicMapTests = tc => {
 
   t.assert(map1.get('number') === 1, 'client 1 received the update (number)')
   t.assert(map1.get('string') === 'hello Y', 'client 1 received the update (string)')
+  t.assert(map1.get('boolean0') === false, 'client 1 computed the change (boolean)')
+  t.assert(map1.get('boolean1') === true, 'client 1 computed the change (boolean)')
   t.compare(map1.get('object'), { key: { key2: 'value' } }, 'client 1 received the update (object)')
   t.assert(map1.get('y-map').get('y-array').get(0) === -1, 'client 1 received the update (type)')
 
   // compare disconnected user
   t.assert(map2.get('number') === 1, 'client 2 received the update (number) - was disconnected')
   t.assert(map2.get('string') === 'hello Y', 'client 2 received the update (string) - was disconnected')
+  t.assert(map2.get('boolean0') === false, 'client 2 computed the change (boolean)')
+  t.assert(map2.get('boolean1') === true, 'client 2 computed the change (boolean)')
   t.compare(map2.get('object'), { key: { key2: 'value' } }, 'client 2 received the update (object) - was disconnected')
   t.assert(map2.get('y-map').get('y-array').get(0) === -1, 'client 2 received the update (type) - was disconnected')
   compare(users)
@@ -284,6 +292,104 @@ export const testThrowsAddAndUpdateAndDeleteEvents = tc => {
   compare(users)
 }
 
+/**
+ * @param {t.TestCase} tc
+ */
+export const testChangeEvent = tc => {
+  const { map0, users } = init(tc, { users: 2 })
+  /**
+   * @type {any}
+   */
+  let changes = null
+  /**
+   * @type {any}
+   */
+  let keyChange = null
+  map0.observe(e => {
+    changes = e.changes
+  })
+  map0.set('a', 1)
+  keyChange = changes.keys.get('a')
+  t.assert(changes !== null && keyChange.action === 'add' && keyChange.oldValue === undefined)
+  map0.set('a', 2)
+  keyChange = changes.keys.get('a')
+  t.assert(changes !== null && keyChange.action === 'update' && keyChange.oldValue === 1)
+  users[0].transact(() => {
+    map0.set('a', 3)
+    map0.set('a', 4)
+  })
+  keyChange = changes.keys.get('a')
+  t.assert(changes !== null && keyChange.action === 'update' && keyChange.oldValue === 2)
+  users[0].transact(() => {
+    map0.set('b', 1)
+    map0.set('b', 2)
+  })
+  keyChange = changes.keys.get('b')
+  t.assert(changes !== null && keyChange.action === 'add' && keyChange.oldValue === undefined)
+  users[0].transact(() => {
+    map0.set('c', 1)
+    map0.delete('c')
+  })
+  t.assert(changes !== null && changes.keys.size === 0)
+  users[0].transact(() => {
+    map0.set('d', 1)
+    map0.set('d', 2)
+  })
+  keyChange = changes.keys.get('d')
+  t.assert(changes !== null && keyChange.action === 'add' && keyChange.oldValue === undefined)
+  compare(users)
+}
+
+/**
+ * @param {t.TestCase} tc
+ */
+export const testYmapEventExceptionsShouldCompleteTransaction = tc => {
+  const doc = new Y.Doc()
+  const map = doc.getMap('map')
+
+  let updateCalled = false
+  let throwingObserverCalled = false
+  let throwingDeepObserverCalled = false
+  doc.on('update', () => {
+    updateCalled = true
+  })
+
+  const throwingObserver = () => {
+    throwingObserverCalled = true
+    throw new Error('Failure')
+  }
+
+  const throwingDeepObserver = () => {
+    throwingDeepObserverCalled = true
+    throw new Error('Failure')
+  }
+
+  map.observe(throwingObserver)
+  map.observeDeep(throwingDeepObserver)
+
+  t.fails(() => {
+    map.set('y', '2')
+  })
+
+  t.assert(updateCalled)
+  t.assert(throwingObserverCalled)
+  t.assert(throwingDeepObserverCalled)
+
+  // check if it works again
+  updateCalled = false
+  throwingObserverCalled = false
+  throwingDeepObserverCalled = false
+  t.fails(() => {
+    map.set('z', '3')
+  })
+
+  t.assert(updateCalled)
+  t.assert(throwingObserverCalled)
+  t.assert(throwingDeepObserverCalled)
+
+  t.assert(map.get('z') === '3')
+}
+
 /**
  * @param {t.TestCase} tc
  */
@@ -320,7 +426,7 @@ export const testYmapEventHasCorrectValueWhenSettingAPrimitiveFromOtherUser = tc
 }
 
 /**
- * @type {Array<function(TestYInstance,prng.PRNG):void>}
+ * @type {Array<function(Doc,prng.PRNG):void>}
  */
 const mapTransactions = [
   function set (user, gen) {

tests/y-text.tests.js

@@ -1,6 +1,6 @@
-import { init, compare } from './testHelper.js'
-
+import * as Y from './testHelper.js'
 import * as t from 'lib0/testing.js'
+const { init, compare } = Y
 
 /**
  * @param {t.TestCase} tc
@@ -27,6 +27,13 @@ export const testBasicInsertAndDelete = tc => {
   text0.delete(1, 1)
   t.assert(text0.toString() === 'b', 'Basic delete works (position 1)')
   t.compare(delta, [{ retain: 1 }, { delete: 1 }])
+
+  users[0].transact(() => {
+    text0.insert(0, '1')
+    text0.delete(0, 1)
+  })
+  t.compare(delta, [])
+
   compare(users)
 }
 
@@ -56,7 +63,7 @@ export const testBasicFormat = tc => {
   t.compare(text0.toDelta(), [{ insert: 'zb', attributes: { bold: true } }])
   t.compare(delta, [{ insert: 'z', attributes: { bold: true } }])
   // @ts-ignore
-  t.assert(text0._start.right.right.right.string === 'b', 'Does not insert duplicate attribute marker')
+  t.assert(text0._start.right.right.right.content.str === 'b', 'Does not insert duplicate attribute marker')
   text0.insert(0, 'y')
   t.assert(text0.toString() === 'yzb')
   t.compare(text0.toDelta(), [{ insert: 'y' }, { insert: 'zb', attributes: { bold: true } }])
@@ -67,3 +74,78 @@ export const testBasicFormat = tc => {
   t.compare(delta, [{ retain: 1 }, { retain: 1, attributes: { bold: null } }])
   compare(users)
 }
+
+/**
+ * @param {t.TestCase} tc
+ */
+export const testGetDeltaWithEmbeds = tc => {
+  const { text0 } = init(tc, { users: 1 })
+  text0.applyDelta([{
+    insert: { linebreak: 's' }
+  }])
+  t.compare(text0.toDelta(), [{
+    insert: { linebreak: 's' }
+  }])
+}
+
+/**
+ * @param {t.TestCase} tc
+ */
+export const testSnapshot = tc => {
+  const { text0 } = init(tc, { users: 1 })
+  const doc0 = /** @type {Y.Doc} */ (text0.doc)
+  doc0.gc = false
+  text0.applyDelta([{
+    insert: 'abcd'
+  }])
+  const snapshot1 = Y.snapshot(doc0)
+  text0.applyDelta([{
+    retain: 1
+  }, {
+    insert: 'x'
+  }, {
+    delete: 1
+  }])
+  const snapshot2 = Y.snapshot(doc0)
+  text0.applyDelta([{
+    retain: 2
+  }, {
+    delete: 3
+  }, {
+    insert: 'x'
+  }, {
+    delete: 1
+  }])
+  const state1 = text0.toDelta(snapshot1)
+  t.compare(state1, [{ insert: 'abcd' }])
+  const state2 = text0.toDelta(snapshot2)
+  t.compare(state2, [{ insert: 'axcd' }])
+  const state2Diff = text0.toDelta(snapshot2, snapshot1)
+  // @ts-ignore Remove userid info
+  state2Diff.forEach(v => {
+    if (v.attributes && v.attributes.ychange) {
+      delete v.attributes.ychange.user
+    }
+  })
+  t.compare(state2Diff, [{ insert: 'a' }, { insert: 'x', attributes: { ychange: { type: 'added' } } }, { insert: 'b', attributes: { ychange: { type: 'removed' } } }, { insert: 'cd' }])
+}
+
+/**
+ * @param {t.TestCase} tc
+ */
+export const testSnapshotDeleteAfter = tc => {
+  const { text0 } = init(tc, { users: 1 })
+  const doc0 = /** @type {Y.Doc} */ (text0.doc)
+  doc0.gc = false
+  text0.applyDelta([{
+    insert: 'abcd'
+  }])
+  const snapshot1 = Y.snapshot(doc0)
+  text0.applyDelta([{
+    retain: 4
+  }, {
+    insert: 'e'
+  }])
+  const state1 = text0.toDelta(snapshot1)
+  t.compare(state1, [{ insert: 'abcd' }])
+}

tsconfig.json

@@ -36,8 +36,13 @@
 
     /* Module Resolution Options */
     "moduleResolution": "node",            /* Specify module resolution strategy: 'node' (Node.js) or 'classic' (TypeScript pre-1.6). */
-    // "baseUrl": "./",                       /* Base directory to resolve non-absolute module names. */
-    // "paths": {},                           /* A series of entries which re-map imports to lookup locations relative to the 'baseUrl'. */
+    "baseUrl": "./",                       /* Base directory to resolve non-absolute module names. */
+    "paths": {
+      "yjs": ["./src/index.js"],
+      "lib0/*": ["node_modules/lib0/*"],
+      "lib0/set.js": ["node_modules/lib0/set.js"],
+      "lib0/function.js": ["node_modules/lib0/function.js"]
+    },                           /* A series of entries which re-map imports to lookup locations relative to the 'baseUrl'. */
     // "rootDirs": [],                        /* List of root folders whose combined content represents the structure of the project at runtime. */
     // "typeRoots": [],                       /* List of folders to include type definitions from. */
     // "types": [],                           /* Type declaration files to be included in compilation. */
@@ -58,5 +63,5 @@
     // "types": ["./src/utils/typedefs.js"]
   },
   "include": ["./src/**/*", "./tests/**/*"],
-  "exclude": ["../lib0/**/*", "node_modules"]
+  "exclude": ["../lib0/**/*", "node_modules/**/*", "dist", "dist/**/*.js"]
 }