13.6.18

Readme fixes

.github/workflows/node.js.yml

@@ -16,16 +16,16 @@ jobs:
 
     strategy:
       matrix:
-        node-version: [16.x, 18.x]
+        node-version: [16.x, 20.x]
 
     steps:
-    - uses: actions/checkout@v2
+    - uses: actions/checkout@v4
     - name: Use Node.js ${{ matrix.node-version }}
-      uses: actions/setup-node@v1
+      uses: actions/setup-node@v3
       with:
         node-version: ${{ matrix.node-version }}
     - run: npm ci
     - run: npm run lint
-    - run: npm run test-extensive
+    - run: npm run test
       env:
         CI: true

INTERNALS.md

@@ -26,7 +26,7 @@ article](https://blog.kevinjahns.de/are-crdts-suitable-for-shared-editing/).
 
 Each client is assigned a unique *clientID* property on first insert. This is a
 random 53-bit integer (53 bits because that fits in the javascript safe integer
-range).
+range \[JavaScript uses IEEE 754 floats\]).
 
 ## List items
 
@@ -88,7 +88,7 @@ When a local insert happens, Yjs needs to map the insert position in the
 document (eg position 1000) to an ID. With just the linked list, this would
 require a slow O(n) linear scan of the list. But when editing a document, most
 inserts are either at the same position as the last insert, or nearby. To
-improve performance, Yjs stores a cache of the 10 most recently looked up
+improve performance, Yjs stores a cache of the 80 most recently looked up
 insert positions in the document. This is consulted and updated when a position
 is looked up to improve performance in the average case. The cache is updated
 using a heuristic that is still changing (currently, it is updated when a new
@@ -149,8 +149,8 @@ concepts that can be used to create a custom network protocol:
 
 * `update`: The Yjs document can be encoded to an *update* object that can be
   parsed to reconstruct the document. Also every change on the document fires
-an incremental document updates that allows clients to sync with each other.
-The update object is an Uint8Array that efficiently encodes `Item` objects and
+an incremental document update that allows clients to sync with each other.
+The update object is a Uint8Array that efficiently encodes `Item` objects and
 the delete set.
 * `state vector`: A state vector defines the known state of each user (a set of
   tuples `(client, clock)`). This object is also efficiently encoded as a

LICENSE

@@ -1,7 +1,7 @@
 The MIT License (MIT)
 
-Copyright (c) 2014
-  - Kevin Jahns <kevin.jahns@rwth-aachen.de>.
+Copyright (c) 2023
+  - Kevin Jahns <kevin.jahns@protonmail.com>.
   - Chair of Computer Science 5 (Databases & Information Systems), RWTH Aachen University, Germany
 
 Permission is hereby granted, free of charge, to any person obtaining a copy

README.md

@@ -32,13 +32,34 @@ Otherwise you can find help on our community [discussion board](https://discuss.
 Please contribute to the project financially - especially if your company relies
 on Yjs. [![Become a Sponsor](https://img.shields.io/static/v1?label=Become%20a%20Sponsor&message=%E2%9D%A4&logo=GitHub&style=flat&color=d42f2d)](https://github.com/sponsors/dmonad)
 
+## Professional Support
+
+* [Support Contract with the Maintainer](https://github.com/sponsors/dmonad) -
+By contributing financially to the open-source Yjs project, you can receive
+professional support directly from the author. This includes the opportunity for
+weekly video calls to discuss your specific challenges.
+* [Synergy Codes](https://synergycodes.com/yjs-services/) - Specializing in
+consulting and developing real-time collaborative editing solutions for visual
+apps, Synergy Codes focuses on interactive diagrams, complex graphs, charts, and
+various data visualization types. Their expertise empowers developers to build
+engaging and interactive visual experiences leveraging the power of Yjs. See
+their work in action at [Visual Collaboration
+Showcase](https://yjs-diagram.synergy.codes/).
+
 ## Who is using Yjs
 
 * [AFFiNE](https://affine.pro/) A local-first, privacy-first, open source
-  knowledge base. 🏅
-* [Dynaboard](https://dynaboard.com/) Build web apps collaboratively. :star2:
-* [Sana](https://sanalabs.com/) A learning platform with collaborative text
-  editing powered by Yjs.
+  knowledge base. :star2:
+* [Huly](https://huly.io/) - Open Source All-in-One Project Management Platform :star2:
+* [Cargo](https://cargo.site/) Site builder for designers and artists :star2:
+* [Gitbook](https://gitbook.com) Knowledge management for technical teams :star2:
+* [Evernote](https://evernote.com) Note-taking app :star2:
+* [Lessonspace](https://thelessonspace.com) Enterprise platform for virtual
+  classrooms and online training :star2:
+* [Ellipsus](ellipsus.com) - Collaborative writing app for storytelling etc.
+  Supports versioning, change attribution, and "blame". A solution for the whole
+  publishing process (also selling) :star:
+* [Dynaboard](https://dynaboard.com/) Build web apps collaboratively. :star:
 * [Relm](https://www.relm.us/) A collaborative gameworld for teamwork and
   community. :star:
 * [Room.sh](https://room.sh/) A meeting application with integrated
@@ -47,25 +68,59 @@ on Yjs. [![Become a Sponsor](https://img.shields.io/static/v1?label=Become%20a%2
   Nimbus Web. :star:
 * [Pluxbox RadioManager](https://getradiomanager.com/) A web-based app to
   collaboratively organize radio broadcasts. :star:
+* [modyfi](https://www.modyfi.com) - Modyfi is the design platform built for
+  multidisciplinary designers. Design, generate, animate, and more — without
+  switching between apps. :star:
+* [Sana](https://sanalabs.com/) A learning platform with collaborative text
+  editing powered by Yjs.
 * [Serenity Notes](https://www.serenity.re/en/notes) End-to-end encrypted
   collaborative notes app.
-* [PRSM](https://prsm.uk/) Collaborative mind-mapping and system visualisation. *[(source)](https://github.com/micrology/prsm)*
+* [PRSM](https://prsm.uk/) Collaborative mind-mapping and system visualisation.
+  *[(source)](https://github.com/micrology/prsm)*
 * [Alldone](https://alldone.app/) A next-gen project management and
   collaboration platform.
 * [Living Spec](https://livingspec.com/) A modern way for product teams to collaborate.
 * [Slidebeamer](https://slidebeamer.com/) Presentation app.
 * [BlockSurvey](https://blocksurvey.io) End-to-end encryption for your forms/surveys.
 * [Skiff](https://skiff.org/) Private, decentralized workspace.
+* [JupyterLab](https://jupyter.org/) Collaborative computational Notebooks
+* [JupyterCad](https://jupytercad.readthedocs.io/en/latest/) Extension to
+  JupyterLab that enables collaborative editing of 3d FreeCAD Models.
 * [Hyperquery](https://hyperquery.ai/) A collaborative data workspace for
   sharing analyses, documentation, spreadsheets, and dashboards.
 * [Nosgestesclimat](https://nosgestesclimat.fr/groupe) The french carbon
   footprint calculator has a group P2P mode based on yjs
+* [oorja.io](https://oorja.io) Online meeting spaces extensible with
+  collaborative apps, end-to-end encrypted.
+* [LegendKeeper](https://legendkeeper.com) Collaborative campaign planner and
+  worldbuilding app for tabletop RPGs.
+* [IllumiDesk](https://illumidesk.com/) Build courses and content with A.I.
+* [btw](https://www.btw.so) Open-source Medium alternative
+* [AWS SageMaker](https://aws.amazon.com/sagemaker/) Tools for building Machine
+  Learning Models
+* [linear](https://linear.app) Streamline issues, projects, and product roadmaps.
+* [btw](https://www.btw.so) - Personal website builder
+* [AWS SageMaker](https://aws.amazon.com/sagemaker/) - Machine Learning Service
+* [Arkiter](https://www.arkiter.com/) - Live interview software
+* [Appflowy](https://www.appflowy.io/) - They use Yrs
+* [Multi.app](https://multi.app) - Multiplayer app sharing: Point, draw and edit
+  in shared apps as if they're on your computer. They are using Yrs.
+* [AppMaster](https://appmaster.io) A No-Code platform for creating
+  production-ready applications with source code generation.
+* [Synthesia](https://www.synthesia.io) - Collaborative Video Editor
+* [thinkdeli](https://thinkdeli.com) - A fast and simple notes app powered by AI
+* [ourboard](https://github.com/raimohanska/ourboard) - A collaborative whiteboard
+  applicaiton
+* [Ellie.ai](https://ellie.ai) - Data Product Design and Collaboration
+* [GoPeer](https://gopeer.org/) - Collaborative tutoring
+* [screen.garden](https://screen.garden) Collaborative backend for PKM apps.
 
 ## Table of Contents
 
 * [Overview](#Overview)
   * [Bindings](#Bindings)
   * [Providers](#Providers)
+  * [Ports](#Ports)
 * [Getting Started](#Getting-Started)
 * [API](#API)
   * [Shared Types](#Shared-Types)
@@ -92,9 +147,11 @@ are implemented in separate modules.
 | [Monaco](https://microsoft.github.io/monaco-editor/) | ✔ | [y-monaco](https://github.com/yjs/y-monaco) | [demo](https://demos.yjs.dev/monaco/monaco.html) |
 | [Slate](https://github.com/ianstormtaylor/slate) | ✔ | [slate-yjs](https://github.com/bitphinix/slate-yjs) | [demo](https://bitphinix.github.io/slate-yjs-example) |
 | [BlockSuite](https://github.com/toeverything/blocksuite) | ✔ | (native) | [demo](https://blocksuite-toeverything.vercel.app/?init) |
+| [Lexical](https://lexical.dev/) | ✔ | (native) | [demo](https://lexical.dev/docs/collaboration/react#see-it-in-action) |
 | [valtio](https://github.com/pmndrs/valtio) |  | [valtio-yjs](https://github.com/dai-shi/valtio-yjs) | [demo](https://codesandbox.io/s/valtio-yjs-demo-ox3iy) |
 | [immer](https://github.com/immerjs/immer) |  | [immer-yjs](https://github.com/sep2/immer-yjs) | [demo](https://codesandbox.io/s/immer-yjs-demo-6e0znb) |
 | React / Vue / Svelte / MobX | | [SyncedStore](https://syncedstore.org) | [demo](https://syncedstore.org/docs/react) |
+| [mobx-keystone](https://mobx-keystone.js.org/) |  | [mobx-keystone-yjs](https://github.com/xaviergonz/mobx-keystone/tree/master/packages/mobx-keystone-yjs) | [demo](https://mobx-keystone.js.org/examples/yjs-binding) |
 
 ### Providers
 
@@ -103,7 +160,20 @@ and storing shared data for offline usage is quite a hassle. **Providers**
 manage all that for you and are the perfect starting point for your
 collaborative app.
 
+> This list of providers is incomplete. Please open PRs to add your providers to
+> this list!
+
+#### Connection Providers
+
 <dl>
+  <dt><a href="https://github.com/yjs/y-websocket">y-websocket</a></dt>
+  <dd>
+A module that contains a simple websocket backend and a websocket client that
+connects to that backend. <a href="https://github.com/yjs/y-redis/"><b>y-redis</b></a>,
+<b>y-sweet</b>, <b>ypy-websocket</b> and <a href="https://tiptap.dev/docs/hocuspocus/introduction">
+<b>Hocuspocus</b></a> (see below) are alternative
+backends to y-websocket.
+  </dd>
   <dt><a href="https://github.com/yjs/y-webrtc">y-webrtc</a></dt>
   <dd>
 Propagates document updates peer-to-peer using WebRTC. The peers exchange
@@ -112,17 +182,26 @@ are available. Communication over the signaling servers can be encrypted by
 providing a shared secret, keeping the connection information and the shared
 document private.
   </dd>
-  <dt><a href="https://github.com/yjs/y-websocket">y-websocket</a></dt>
+  <dt><a href="https://github.com/liveblocks/liveblocks">@liveblocks/yjs</a></dt>
   <dd>
-A module that contains a simple websocket backend and a websocket client that
-connects to that backend. The backend can be extended to persist updates in a
-leveldb database.
+<a href="https://liveblocks.io/document/yjs">Liveblocks Yjs</a> provides a fully
+hosted WebSocket infrastructure and persisted data store for Yjs
+documents. No configuration or maintenance is required. It also features
+Yjs webhook events, REST API to read and update Yjs documents, and a
+browser DevTools extension.
   </dd>
-  <dt><a href="https://github.com/yjs/y-indexeddb">y-indexeddb</a></dt>
+  <dt><a href="https://github.com/drifting-in-space/y-sweet">y-sweet</a></dt>
   <dd>
-Efficiently persists document updates to the browsers indexeddb database.
-The document is immediately available and only diffs need to be synced through the
-network provider.
+A standalone yjs server with persistence to S3 or filesystem. They offer a
+<a href="https://y-sweet.cloud">cloud service</a> as well.
+  </dd>
+  <dt><a href="https://github.com/ueberdosis/hocuspocus">Hocuspocus</a></dt>
+  <dd>
+A standalone extensible yjs server with sqlite persistence, webhooks, auth and more.
+  </dd>
+  <dt><a href="https://docs.partykit.io/reference/y-partykit-api/">PartyKit</a></dt>
+  <dd>
+Cloud service for building multiplayer apps.
   </dd>
   <dt><a href="https://github.com/marcopolo/y-libp2p">y-libp2p</a></dt>
   <dd>
@@ -145,14 +224,79 @@ Use Matrix as transport and storage of Yjs updates, so you can focus building
 your client app and Matrix can provide powerful features like Authentication,
 Authorization, Federation, hosting (self-hosting or SaaS) and even End-to-End
 Encryption (E2EE).
-</dd>
+  </dd>
+  <dt><a href="https://github.com/y-crdt/yrb-actioncable">yrb-actioncable</a></dt>
+  <dd>
+An ActionCable companion for Yjs clients. There is a fitting
+<a href="https://github.com/y-crdt/yrb-redis">redis extension</a> as well.
+  </dd>
+  <dt><a href="https://github.com/y-crdt/ypy-websocket">ypy-websocket</a></dt>
+  <dd>
+Websocket backend, written in Python.
+  </dd>
+  <dt><a href="https://tinybase.org/">Tinybase</a></dt>
+  <dd>
+The reactive data store for local-first apps. They support multiple CRDTs and
+    different network technologies.
+  </dd>
+  <dt><a href="https://codeberg.org/webxdc/y-webxdc">y-webxdc</a></dt>
+  <dd>
+Provider for sharing data in <a href="https://webxdc.org">webxdc chat apps</a>.
+  </dd>
+</dl>
+
+#### Persistence Providers
+
+<dl>
+  <dt><a href="https://github.com/yjs/y-indexeddb">y-indexeddb</a></dt>
+  <dd>
+Efficiently persists document updates to the browsers indexeddb database.
+The document is immediately available and only diffs need to be synced through the
+network provider.
+  </dd>
   <dt><a href="https://github.com/MaxNoetzold/y-mongodb-provider">y-mongodb-provider</a></dt>
   <dd>
 Adds persistent storage to a server with MongoDB. Can be used with the
 y-websocket provider.
-</dd>
+  </dd>
+  <dt><a href="https://github.com/toeverything/AFFiNE/tree/master/packages/y-indexeddb">
+@toeverything/y-indexeddb</a></dt>
+  <dd>
+Like y-indexeddb, but with sub-documents support and fully TypeScript.
+  </dd>
+  <dt><a href="https://github.com/podraven/y-fire">y-fire</a></dt>
+  <dd>
+A database and connection provider for Yjs based on Firestore.
+  </dd>
+  <dt><a href="https://github.com/malte-j/y-op-sqlite">y-op-sqlite</a></dt>
+  <dd>
+  Persist YJS updates in your React Native app using
+   <a href="https://github.com/OP-Engineering/op-sqlite">op-sqlite</a>
+  , the fastest SQLite library for React Native.  
+  </dd>
+  <dt><a href="https://github.com/MaxNoetzold/y-postgresql">y-postgresql</a></dt>
+  <dd>
+  Provides persistent storage for a web server using PostgreSQL and
+  is easily compatible with y-websocket.  
+  </dd>
 </dl>
 
+# Ports
+
+There are several Yjs-compatible ports to other programming languages.
+
+* [y-octo](https://github.com/toeverything/y-octo) - Rust implementation by
+[AFFiNE](https://affine.pro)
+* [y-crdt](https://github.com/y-crdt/y-crdt) - Rust implementation with multiple
+language bindings to other languages
+  * [yrs](https://github.com/y-crdt/y-crdt/tree/main/yrs) - Rust interface
+  * [ypy](https://github.com/y-crdt/ypy) - Python binding
+  * [yrb](https://github.com/y-crdt/yrb) - Ruby binding
+  * [yswift](https://github.com/y-crdt/yswift) - Swift binding
+  * [yffi](https://github.com/y-crdt/y-crdt/tree/main/yffi) - C-FFI
+  * [ywasm](https://github.com/y-crdt/y-crdt/tree/main/ywasm) - WASM binding
+* [ycs](https://github.com/yjs/ycs) - .Net compatible C# implementation.
+
 ## Getting Started
 
 Install Yjs and a provider with your favorite package manager:
@@ -164,7 +308,7 @@ npm i yjs y-websocket
 Start the y-websocket server:
 
 ```sh
-PORT=1234 node ./node_modules/y-websocket/bin/server.js
+PORT=1234 node ./node_modules/y-websocket/bin/server.cjs
 ```
 
 ### Example: Observe types
@@ -648,6 +792,8 @@ type. Doesn't log types that have not been defined (using
   <dd>Define a shared Y.Map type. Is equivalent to <code>y.get(string, Y.Map)</code>.</dd>
   <b><code>getText(string):Y.Text</code></b>
   <dd>Define a shared Y.Text type. Is equivalent to <code>y.get(string, Y.Text)</code>.</dd>
+  <b><code>getXmlElement(string, string):Y.XmlElement</code></b>
+  <dd>Define a shared Y.XmlElement type. Is equivalent to <code>y.get(string, Y.XmlElement)</code>.</dd>
   <b><code>getXmlFragment(string):Y.XmlFragment</code></b>
   <dd>Define a shared Y.XmlFragment type. Is equivalent to <code>y.get(string, Y.XmlFragment)</code>.</dd>
   <b><code>on(string, function)</code></b>
@@ -662,7 +808,8 @@ type. Doesn't log types that have not been defined (using
   <b><code>on('update', function(updateMessage:Uint8Array, origin:any, Y.Doc):void)</code></b>
   <dd>
 Listen to document updates. Document updates must be transmitted to all other
-peers. You can apply document updates in any order and multiple times.
+peers. You can apply document updates in any order and multiple times. Use `updateV2`
+to receive V2 events.
   </dd>
   <b><code>on('beforeTransaction', function(Y.Transaction, Y.Doc):void)</code></b>
   <dd>Emitted before each transaction.</dd>
@@ -754,7 +901,7 @@ const diff2 = Y.diffUpdate(currentState2, stateVector1)
 
 // sync clients
 currentState1 = Y.mergeUpdates([currentState1, diff2])
-currentState1 = Y.mergeUpdates([currentState1, diff1])
+currentState2 = Y.mergeUpdates([currentState2, diff1])
 ```
 
 #### Obfuscating Updates
@@ -784,11 +931,13 @@ ydoc2.getText().toString() // => "00000000000"
 #### Using V2 update format
 
 Yjs implements two update formats. By default you are using the V1 update format.
-You can opt-in into the V2 update format wich provides much better compression.
+You can opt-in into the V2 update format which provides much better compression.
 It is not yet used by all providers. However, you can already use it if
 you are building your own provider. All below functions are available with the
-suffix "V2". E.g. `Y.applyUpdate` ⇒ `Y.applyUpdateV2`. We also support conversion
-functions between both formats: `Y.convertUpdateFormatV1ToV2` & `Y.convertUpdateFormatV2ToV1`.
+suffix "V2". E.g. `Y.applyUpdate` ⇒ `Y.applyUpdateV2`. Also when listening to updates
+you need to specifically need listen for V2 events e.g. `yDoc.on('updateV2', …)`.
+We also support conversion functions between both formats:
+`Y.convertUpdateFormatV1ToV2` & `Y.convertUpdateFormatV2ToV1`.
 
 #### Update API
 
@@ -1033,7 +1182,7 @@ doc.transact(() => {
   ytext.insert(0, 'abc')
 }, 41)
 undoManager.undo()
-ytext.toString() // => '' (not tracked because 41 is not an instance of
+ytext.toString() // => 'abc' (not tracked because 41 is not an instance of
                  //        `trackedTransactionorigins`)
 ytext.delete(0, 3) // revert change
 

package.json

@@ -1,6 +1,6 @@
 {
   "name": "yjs",
-  "version": "13.6.6",
+  "version": "13.6.18",
   "description": "Shared Editing Library",
   "main": "./dist/yjs.cjs",
   "module": "./dist/yjs.mjs",
@@ -12,9 +12,10 @@
     "url": "https://github.com/sponsors/dmonad"
   },
   "scripts": {
+    "clean": "rm -rf dist docs",
     "test": "npm run dist && node ./dist/tests.cjs --repetition-time 50",
     "test-extensive": "npm run lint && npm run dist && node ./dist/tests.cjs --production --repetition-time 10000",
-    "dist": "rm -rf dist && rollup -c && tsc",
+    "dist": "npm run clean && rollup -c && tsc",
     "watch": "rollup -wc",
     "lint": "markdownlint README.md && standard && tsc",
     "docs": "rm -rf docs; jsdoc --configure ./.jsdoc.json --verbose --readme ./README.md --package ./package.json || true",
@@ -75,7 +76,7 @@
   },
   "homepage": "https://docs.yjs.dev",
   "dependencies": {
-    "lib0": "^0.2.74"
+    "lib0": "^0.2.86"
   },
   "devDependencies": {
     "@rollup/plugin-commonjs": "^24.0.1",

src/index.js

@@ -18,8 +18,10 @@ export {
   Item,
   AbstractStruct,
   GC,
+  Skip,
   ContentBinary,
   ContentDeleted,
+  ContentDoc,
   ContentEmbed,
   ContentFormat,
   ContentJSON,
@@ -50,6 +52,7 @@ export {
   getItem,
   typeListToArraySnapshot,
   typeMapGetSnapshot,
+  typeMapGetAllSnapshot,
   createDocFromSnapshot,
   iterateDeletedStructs,
   applyUpdate,
@@ -93,7 +96,11 @@ export {
   obfuscateUpdate,
   obfuscateUpdateV2,
   UpdateEncoderV1,
+  UpdateEncoderV2,
+  UpdateDecoderV1,
+  UpdateDecoderV2,
   equalDeleteSets,
+  mergeDeleteSets,
   snapshotContainsUpdate
 } from './internals.js'
 

src/internals.js

@@ -1,4 +1,3 @@
-
 export * from './utils/AbstractConnector.js'
 export * from './utils/DeleteSet.js'
 export * from './utils/Doc.js'

src/structs/AbstractStruct.js

@@ -1,4 +1,3 @@
-
 import {
   UpdateEncoderV1, UpdateEncoderV2, ID, Transaction // eslint-disable-line
 } from '../internals.js'

src/structs/ContentDeleted.js

@@ -1,4 +1,3 @@
-
 import {
   addToDeleteSet,
   UpdateDecoderV1, UpdateDecoderV2, UpdateEncoderV1, UpdateEncoderV2, StructStore, Item, Transaction // eslint-disable-line

src/structs/ContentDoc.js

@@ -1,4 +1,3 @@
-
 import {
   Doc, UpdateDecoderV1, UpdateDecoderV2, UpdateEncoderV1, UpdateEncoderV2, StructStore, Transaction, Item // eslint-disable-line
 } from '../internals.js'

src/structs/ContentEmbed.js

@@ -1,4 +1,3 @@
-
 import {
   UpdateDecoderV1, UpdateDecoderV2, UpdateEncoderV1, UpdateEncoderV2, StructStore, Item, Transaction // eslint-disable-line
 } from '../internals.js'

src/structs/ContentFormat.js

@@ -1,4 +1,3 @@
-
 import {
   YText, UpdateDecoderV1, UpdateDecoderV2, UpdateEncoderV1, UpdateEncoderV2, Item, StructStore, Transaction // eslint-disable-line
 } from '../internals.js'

src/structs/ContentType.js

@@ -1,4 +1,3 @@
-
 import {
   readYArray,
   readYMap,
@@ -108,7 +107,7 @@ export class ContentType {
     while (item !== null) {
       if (!item.deleted) {
         item.delete(transaction)
-      } else {
+      } else if (item.id.clock < (transaction.beforeState.get(item.id.client) || 0)) {
         // This 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
@@ -120,7 +119,7 @@ export class ContentType {
     this.type._map.forEach(item => {
       if (!item.deleted) {
         item.delete(transaction)
-      } else {
+      } else if (item.id.clock < (transaction.beforeState.get(item.id.client) || 0)) {
         // same as above
         transaction._mergeStructs.push(item)
       }

src/structs/GC.js

@@ -1,4 +1,3 @@
-
 import {
   AbstractStruct,
   addStruct,

src/structs/Item.js

@@ -1,4 +1,3 @@
-
 import {
   GC,
   getState,
@@ -389,9 +388,8 @@ export class Item extends AbstractStruct {
     }
     if ((this.left && this.left.constructor === GC) || (this.right && this.right.constructor === GC)) {
       this.parent = null
-    }
-    // only set parent if this shouldn't be garbage collected
-    if (!this.parent) {
+    } else if (!this.parent) {
+      // only set parent if this shouldn't be garbage collected
       if (this.left && this.left.constructor === Item) {
         this.parent = this.left.parent
         this.parentSub = this.left.parentSub

src/structs/Skip.js

@@ -1,4 +1,3 @@
-
 import {
   AbstractStruct,
   UpdateEncoderV1, UpdateEncoderV2, StructStore, Transaction, ID // eslint-disable-line

src/types/AbstractType.js

@@ -1,4 +1,3 @@
-
 import {
   removeEventHandlerListener,
   callEventHandlerListeners,
@@ -317,6 +316,10 @@ export class AbstractType {
   }
 
   /**
+   * Makes a copy of this data type that can be included somewhere else.
+   *
+   * Note that the content is only readable _after_ it has been included somewhere in the Ydoc.
+   *
    * @return {AbstractType<EventType>}
    */
   clone () {
@@ -478,7 +481,7 @@ export const typeListToArraySnapshot = (type, snapshot) => {
 }
 
 /**
- * Executes a provided function on once on overy element of this YArray.
+ * Executes a provided function on once on every element of this YArray.
  *
  * @param {AbstractType<any>} type
  * @param {function(any,number,any):void} f A function to execute on every element of this YArray.
@@ -570,7 +573,7 @@ export const typeListCreateIterator = type => {
 }
 
 /**
- * Executes a provided function on once on overy element of this YArray.
+ * Executes a provided function on once on every element of this YArray.
  * Operates on a snapshotted state of the document.
  *
  * @param {AbstractType<any>} type
@@ -683,7 +686,7 @@ export const typeListInsertGenericsAfter = (transaction, parent, referenceItem,
   packJsonContent()
 }
 
-const lengthExceeded = error.create('Length exceeded!')
+const lengthExceeded = () => error.create('Length exceeded!')
 
 /**
  * @param {Transaction} transaction
@@ -696,7 +699,7 @@ const lengthExceeded = error.create('Length exceeded!')
  */
 export const typeListInsertGenerics = (transaction, parent, index, content) => {
   if (index > parent._length) {
-    throw lengthExceeded
+    throw lengthExceeded()
   }
   if (index === 0) {
     if (parent._searchMarker) {
@@ -798,7 +801,7 @@ export const typeListDelete = (transaction, parent, index, length) => {
     n = n.right
   }
   if (length > 0) {
-    throw lengthExceeded
+    throw lengthExceeded()
   }
   if (parent._searchMarker) {
     updateMarkerChanges(parent._searchMarker, startIndex, -startLength + length /* in case we remove the above exception */)
@@ -925,6 +928,34 @@ export const typeMapGetSnapshot = (parent, key, snapshot) => {
   return v !== null && isVisible(v, snapshot) ? v.content.getContent()[v.length - 1] : undefined
 }
 
+/**
+ * @param {AbstractType<any>} parent
+ * @param {Snapshot} snapshot
+ * @return {Object<string,Object<string,any>|number|null|Array<any>|string|Uint8Array|AbstractType<any>|undefined>}
+ *
+ * @private
+ * @function
+ */
+export const typeMapGetAllSnapshot = (parent, snapshot) => {
+  /**
+   * @type {Object<string,any>}
+   */
+  const res = {}
+  parent._map.forEach((value, key) => {
+    /**
+     * @type {Item|null}
+     */
+    let v = value
+    while (v !== null && (!snapshot.sv.has(v.id.client) || v.id.clock >= (snapshot.sv.get(v.id.client) || 0))) {
+      v = v.left
+    }
+    if (v !== null && isVisible(v, snapshot)) {
+      res[key] = v.content.getContent()[v.length - 1]
+    }
+  })
+  return res
+}
+
 /**
  * @param {Map<string,Item>} map
  * @return {IterableIterator<Array<any>>}

src/types/YArray.js

@@ -25,16 +25,7 @@ import { typeListSlice } from './AbstractType.js'
  * @template T
  * @extends YEvent<YArray<T>>
  */
-export class YArrayEvent extends YEvent {
-  /**
-   * @param {YArray<T>} yarray The changed type
-   * @param {Transaction} transaction The transaction object
-   */
-  constructor (yarray, transaction) {
-    super(yarray, transaction)
-    this._transaction = transaction
-  }
-}
+export class YArrayEvent extends YEvent {}
 
 /**
  * A shared Array implementation.
@@ -95,6 +86,10 @@ export class YArray extends AbstractType {
   }
 
   /**
+   * Makes a copy of this data type that can be included somewhere else.
+   *
+   * Note that the content is only readable _after_ it has been included somewhere in the Ydoc.
+   *
    * @return {YArray<T>}
    */
   clone () {
@@ -167,9 +162,9 @@ export class YArray extends AbstractType {
   }
 
   /**
-   * Preppends content to this YArray.
+   * Prepends content to this YArray.
    *
-   * @param {Array<T>} content Array of content to preppend.
+   * @param {Array<T>} content Array of content to prepend.
    */
   unshift (content) {
     this.insert(0, content)
@@ -211,7 +206,8 @@ export class YArray extends AbstractType {
   }
 
   /**
-   * Transforms this YArray to a JavaScript Array.
+   * Returns a portion of this YArray into a JavaScript Array selected
+   * from start to end (end not included).
    *
    * @param {number} [start]
    * @param {number} [end]
@@ -244,7 +240,7 @@ export class YArray extends AbstractType {
   }
 
   /**
-   * Executes a provided function once on overy element of this YArray.
+   * Executes a provided function once on every element of this YArray.
    *
    * @param {function(T,number,YArray<T>):void} f A function to execute on every element of this YArray.
    */

src/types/YMap.js

@@ -1,4 +1,3 @@
-
 /**
  * @module YMap
  */
@@ -41,7 +40,7 @@ export class YMapEvent extends YEvent {
  * A shared Map implementation.
  *
  * @extends AbstractType<YMapEvent<MapType>>
- * @implements {Iterable<MapType>}
+ * @implements {Iterable<[string, MapType]>}
  */
 export class YMap extends AbstractType {
   /**
@@ -89,6 +88,10 @@ export class YMap extends AbstractType {
   }
 
   /**
+   * Makes a copy of this data type that can be included somewhere else.
+   *
+   * Note that the content is only readable _after_ it has been included somewhere in the Ydoc.
+   *
    * @return {YMap<MapType>}
    */
   clone () {
@@ -152,7 +155,7 @@ export class YMap extends AbstractType {
   /**
    * Returns the values for each element in the YMap Type.
    *
-   * @return {IterableIterator<any>}
+   * @return {IterableIterator<MapType>}
    */
   values () {
     return iterator.iteratorMap(createMapIterator(this._map), /** @param {any} v */ v => v[1].content.getContent()[v[1].length - 1])
@@ -161,10 +164,10 @@ export class YMap extends AbstractType {
   /**
    * Returns an Iterator of [key, value] pairs
    *
-   * @return {IterableIterator<any>}
+   * @return {IterableIterator<[string, MapType]>}
    */
   entries () {
-    return iterator.iteratorMap(createMapIterator(this._map), /** @param {any} v */ v => [v[0], v[1].content.getContent()[v[1].length - 1]])
+    return iterator.iteratorMap(createMapIterator(this._map), /** @param {any} v */ v => /** @type {any} */ ([v[0], v[1].content.getContent()[v[1].length - 1]]))
   }
 
   /**
@@ -183,7 +186,7 @@ export class YMap extends AbstractType {
   /**
    * Returns an Iterator of [key, value] pairs
    *
-   * @return {IterableIterator<any>}
+   * @return {IterableIterator<[string, MapType]>}
    */
   [Symbol.iterator] () {
     return this.entries()

src/types/YText.js

@@ -1,4 +1,3 @@
-
 /**
  * @module YText
  */
@@ -118,14 +117,15 @@ const findNextPosition = (transaction, pos, count) => {
  * @param {Transaction} transaction
  * @param {AbstractType<any>} parent
  * @param {number} index
+ * @param {boolean} useSearchMarker
  * @return {ItemTextListPosition}
  *
  * @private
  * @function
  */
-const findPosition = (transaction, parent, index) => {
+const findPosition = (transaction, parent, index, useSearchMarker) => {
   const currentAttributes = new Map()
-  const marker = findMarker(parent, index)
+  const marker = useSearchMarker ? findMarker(parent, index) : null
   if (marker) {
     const pos = new ItemTextListPosition(marker.p.left, marker.p, marker.index, currentAttributes)
     return findNextPosition(transaction, pos, index - marker.index)
@@ -201,7 +201,7 @@ const minimizeAttributeChanges = (currPos, attributes) => {
   while (true) {
     if (currPos.right === null) {
       break
-    } else if (currPos.right.deleted || (currPos.right.content.constructor === ContentFormat && equalAttrs(attributes[(/** @type {ContentFormat} */ (currPos.right.content)).key] || null, /** @type {ContentFormat} */ (currPos.right.content).value))) {
+    } else if (currPos.right.deleted || (currPos.right.content.constructor === ContentFormat && equalAttrs(attributes[(/** @type {ContentFormat} */ (currPos.right.content)).key] ?? null, /** @type {ContentFormat} */ (currPos.right.content).value))) {
       //
     } else {
       break
@@ -227,7 +227,7 @@ const insertAttributes = (transaction, parent, currPos, attributes) => {
   // insert format-start items
   for (const key in attributes) {
     const val = attributes[key]
-    const currentVal = currPos.currentAttributes.get(key) || null
+    const currentVal = currPos.currentAttributes.get(key) ?? null
     if (!equalAttrs(currentVal, val)) {
       // save negated attribute (set null if currentVal undefined)
       negatedAttributes.set(key, currentVal)
@@ -389,12 +389,12 @@ const cleanupFormattingGap = (transaction, start, curr, startAttributes, currAtt
       switch (content.constructor) {
         case ContentFormat: {
           const { key, value } = /** @type {ContentFormat} */ (content)
-          const startAttrValue = startAttributes.get(key) || null
+          const startAttrValue = startAttributes.get(key) ?? null
           if (endFormats.get(key) !== content || startAttrValue === value) {
             // Either this format is overwritten or it is not necessary because the attribute already existed.
             start.delete(transaction)
             cleanups++
-            if (!reachedCurr && (currAttributes.get(key) || null) === value && startAttrValue !== value) {
+            if (!reachedCurr && (currAttributes.get(key) ?? null) === value && startAttrValue !== value) {
               if (startAttrValue === null) {
                 currAttributes.delete(key)
               } else {
@@ -769,12 +769,12 @@ export class YTextEvent extends YEvent {
               const { key, value } = /** @type {ContentFormat} */ (item.content)
               if (this.adds(item)) {
                 if (!this.deletes(item)) {
-                  const curVal = currentAttributes.get(key) || null
+                  const curVal = currentAttributes.get(key) ?? null
                   if (!equalAttrs(curVal, value)) {
                     if (action === 'retain') {
                       addOp()
                     }
-                    if (equalAttrs(value, (oldAttributes.get(key) || null))) {
+                    if (equalAttrs(value, (oldAttributes.get(key) ?? null))) {
                       delete attributes[key]
                     } else {
                       attributes[key] = value
@@ -785,7 +785,7 @@ export class YTextEvent extends YEvent {
                 }
               } else if (this.deletes(item)) {
                 oldAttributes.set(key, value)
-                const curVal = currentAttributes.get(key) || null
+                const curVal = currentAttributes.get(key) ?? null
                 if (!equalAttrs(curVal, value)) {
                   if (action === 'retain') {
                     addOp()
@@ -897,6 +897,10 @@ export class YText extends AbstractType {
   }
 
   /**
+   * Makes a copy of this data type that can be included somewhere else.
+   *
+   * Note that the content is only readable _after_ it has been included somewhere in the Ydoc.
+   *
    * @return {YText}
    */
   clone () {
@@ -1120,7 +1124,7 @@ export class YText extends AbstractType {
     const y = this.doc
     if (y !== null) {
       transact(y, transaction => {
-        const pos = findPosition(transaction, this, index)
+        const pos = findPosition(transaction, this, index, !attributes)
         if (!attributes) {
           attributes = {}
           // @ts-ignore
@@ -1138,20 +1142,20 @@ export class YText extends AbstractType {
    *
    * @param {number} index The index to insert the embed at.
    * @param {Object | AbstractType<any>} embed The Object that represents the embed.
-   * @param {TextAttributes} attributes Attribute information to apply on the
+   * @param {TextAttributes} [attributes] Attribute information to apply on the
    *                                    embed
    *
    * @public
    */
-  insertEmbed (index, embed, attributes = {}) {
+  insertEmbed (index, embed, attributes) {
     const y = this.doc
     if (y !== null) {
       transact(y, transaction => {
-        const pos = findPosition(transaction, this, index)
-        insertText(transaction, this, pos, embed, attributes)
+        const pos = findPosition(transaction, this, index, !attributes)
+        insertText(transaction, this, pos, embed, attributes || {})
       })
     } else {
-      /** @type {Array<function>} */ (this._pending).push(() => this.insertEmbed(index, embed, attributes))
+      /** @type {Array<function>} */ (this._pending).push(() => this.insertEmbed(index, embed, attributes || {}))
     }
   }
 
@@ -1170,7 +1174,7 @@ export class YText extends AbstractType {
     const y = this.doc
     if (y !== null) {
       transact(y, transaction => {
-        deleteText(transaction, findPosition(transaction, this, index), length)
+        deleteText(transaction, findPosition(transaction, this, index, true), length)
       })
     } else {
       /** @type {Array<function>} */ (this._pending).push(() => this.delete(index, length))
@@ -1194,7 +1198,7 @@ export class YText extends AbstractType {
     const y = this.doc
     if (y !== null) {
       transact(y, transaction => {
-        const pos = findPosition(transaction, this, index)
+        const pos = findPosition(transaction, this, index, false)
         if (pos.right === null) {
           return
         }

src/types/YXmlElement.js

@@ -8,9 +8,10 @@ import {
   typeMapSet,
   typeMapGet,
   typeMapGetAll,
+  typeMapGetAllSnapshot,
   typeListForEach,
   YXmlElementRefID,
-  YXmlText, ContentType, AbstractType, UpdateDecoderV1, UpdateDecoderV2, UpdateEncoderV1, UpdateEncoderV2, Doc, Item // eslint-disable-line
+  Snapshot, YXmlText, ContentType, AbstractType, UpdateDecoderV1, UpdateDecoderV2, UpdateEncoderV1, UpdateEncoderV2, Doc, Item // eslint-disable-line
 } from '../internals.js'
 
 /**
@@ -19,7 +20,7 @@ import {
 
 /**
  * An YXmlElement imitates the behavior of a
- * {@link https://developer.mozilla.org/en-US/docs/Web/API/Element|Dom Element}.
+ * https://developer.mozilla.org/en-US/docs/Web/API/Element|Dom Element
  *
  * * An YXmlElement has attributes (key value pairs)
  * * An YXmlElement has childElements that must inherit from YXmlElement
@@ -80,6 +81,10 @@ export class YXmlElement extends YXmlFragment {
   }
 
   /**
+   * Makes a copy of this data type that can be included somewhere else.
+   *
+   * Note that the content is only readable _after_ it has been included somewhere in the Ydoc.
+   *
    * @return {YXmlElement<KV>}
    */
   clone () {
@@ -192,12 +197,13 @@ export class YXmlElement extends YXmlFragment {
   /**
    * Returns all attribute name/value pairs in a JSON Object.
    *
+   * @param {Snapshot} [snapshot]
    * @return {{ [Key in Extract<keyof KV,string>]?: KV[Key]}} A JSON Object that describes the attributes.
    *
    * @public
    */
-  getAttributes () {
-    return /** @type {any} */ (typeMapGetAll(this))
+  getAttributes (snapshot) {
+    return /** @type {any} */ (snapshot ? typeMapGetAllSnapshot(this, snapshot) : typeMapGetAll(this))
   }
 
   /**

src/types/YXmlEvent.js

@@ -1,4 +1,3 @@
-
 import {
   YEvent,
   YXmlText, YXmlElement, YXmlFragment, Transaction // eslint-disable-line

src/types/YXmlFragment.js

@@ -163,6 +163,10 @@ export class YXmlFragment extends AbstractType {
   }
 
   /**
+   * Makes a copy of this data type that can be included somewhere else.
+   *
+   * Note that the content is only readable _after_ it has been included somewhere in the Ydoc.
+   *
    * @return {YXmlFragment}
    */
   clone () {
@@ -376,9 +380,9 @@ export class YXmlFragment extends AbstractType {
   }
 
   /**
-   * Preppends content to this YArray.
+   * Prepends content to this YArray.
    *
-   * @param {Array<YXmlElement|YXmlText>} content Array of content to preppend.
+   * @param {Array<YXmlElement|YXmlText>} content Array of content to prepend.
    */
   unshift (content) {
     this.insert(0, content)
@@ -395,7 +399,8 @@ export class YXmlFragment extends AbstractType {
   }
 
   /**
-   * Transforms this YArray to a JavaScript Array.
+   * Returns a portion of this YXmlFragment into a JavaScript Array selected
+   * from start to end (end not included).
    *
    * @param {number} [start]
    * @param {number} [end]
@@ -406,7 +411,7 @@ export class YXmlFragment extends AbstractType {
   }
 
   /**
-   * Executes a provided function on once on overy child element.
+   * Executes a provided function on once on every child element.
    *
    * @param {function(YXmlElement|YXmlText,number, typeof self):void} f A function to execute on every element of this YArray.
    */

src/types/YXmlHook.js

@@ -1,4 +1,3 @@
-
 import {
   YMap,
   YXmlHookRefID,
@@ -30,6 +29,10 @@ export class YXmlHook extends YMap {
   }
 
   /**
+   * Makes a copy of this data type that can be included somewhere else.
+   *
+   * Note that the content is only readable _after_ it has been included somewhere in the Ydoc.
+   *
    * @return {YXmlHook}
    */
   clone () {

src/types/YXmlText.js

@@ -1,4 +1,3 @@
-
 import {
   YText,
   YXmlTextRefID,
@@ -31,6 +30,10 @@ export class YXmlText extends YText {
   }
 
   /**
+   * Makes a copy of this data type that can be included somewhere else.
+   *
+   * Note that the content is only readable _after_ it has been included somewhere in the Ydoc.
+   *
    * @return {YXmlText}
    */
   clone () {

src/utils/AbstractConnector.js

@@ -1,5 +1,4 @@
-
-import { Observable } from 'lib0/observable'
+import { ObservableV2 } from 'lib0/observable'
 
 import {
   Doc // eslint-disable-line
@@ -11,9 +10,9 @@ import {
  * @note This interface is experimental and it is not advised to actually inherit this class.
  *       It just serves as typing information.
  *
- * @extends {Observable<any>}
+ * @extends {ObservableV2<any>}
  */
-export class AbstractConnector extends Observable {
+export class AbstractConnector extends ObservableV2 {
   /**
    * @param {Doc} ydoc
    * @param {any} awareness

src/utils/DeleteSet.js

@@ -1,4 +1,3 @@
-
 import {
   findIndexSS,
   getState,

src/utils/Doc.js

@@ -8,12 +8,13 @@ import {
   YArray,
   YText,
   YMap,
+  YXmlElement,
   YXmlFragment,
   transact,
   ContentDoc, Item, Transaction, YEvent // eslint-disable-line
 } from '../internals.js'
 
-import { Observable } from 'lib0/observable'
+import { ObservableV2 } from 'lib0/observable'
 import * as random from 'lib0/random'
 import * as map from 'lib0/map'
 import * as array from 'lib0/array'
@@ -33,10 +34,26 @@ export const generateNewClientId = random.uint32
  */
 
 /**
- * A Yjs instance handles the state of shared data.
- * @extends Observable<string>
+ * @typedef {Object} DocEvents
+ * @property {function(Doc):void} DocEvents.destroy
+ * @property {function(Doc):void} DocEvents.load
+ * @property {function(boolean, Doc):void} DocEvents.sync
+ * @property {function(Uint8Array, any, Doc, Transaction):void} DocEvents.update
+ * @property {function(Uint8Array, any, Doc, Transaction):void} DocEvents.updateV2
+ * @property {function(Doc):void} DocEvents.beforeAllTransactions
+ * @property {function(Transaction, Doc):void} DocEvents.beforeTransaction
+ * @property {function(Transaction, Doc):void} DocEvents.beforeObserverCalls
+ * @property {function(Transaction, Doc):void} DocEvents.afterTransaction
+ * @property {function(Transaction, Doc):void} DocEvents.afterTransactionCleanup
+ * @property {function(Doc, Array<Transaction>):void} DocEvents.afterAllTransactions
+ * @property {function({ loaded: Set<Doc>, added: Set<Doc>, removed: Set<Doc> }, Doc, Transaction):void} DocEvents.subdocs
  */
-export class Doc extends Observable {
+
+/**
+ * A Yjs instance handles the state of shared data.
+ * @extends ObservableV2<DocEvents>
+ */
+export class Doc extends ObservableV2 {
   /**
    * @param {DocOpts} opts configuration
    */
@@ -113,8 +130,8 @@ export class Doc extends Observable {
         this.whenSynced = provideSyncedPromise()
       }
       this.isSynced = isSynced === undefined || isSynced === true
-      if (!this.isLoaded) {
-        this.emit('load', [])
+      if (this.isSynced && !this.isLoaded) {
+        this.emit('load', [this])
       }
     })
     /**
@@ -170,30 +187,31 @@ export class Doc extends Observable {
   /**
    * Define a shared data type.
    *
-   * Multiple calls of `y.get(name, TypeConstructor)` yield the same result
+   * Multiple calls of `ydoc.get(name, TypeConstructor)` yield the same result
    * and do not overwrite each other. I.e.
-   * `y.define(name, Y.Array) === y.define(name, Y.Array)`
+   * `ydoc.get(name, Y.Array) === ydoc.get(name, Y.Array)`
    *
-   * After this method is called, the type is also available on `y.share.get(name)`.
+   * After this method is called, the type is also available on `ydoc.share.get(name)`.
    *
    * *Best Practices:*
-   * Define all types right after the Yjs instance is created and store them in a separate object.
+   * Define all types right after the Y.Doc instance is created and store them in a separate object.
    * Also use the typed methods `getText(name)`, `getArray(name)`, ..
    *
+   * @template {typeof AbstractType<any>} Type
    * @example
-   *   const y = new Y(..)
+   *   const ydoc = new Y.Doc(..)
    *   const appState = {
-   *     document: y.getText('document')
-   *     comments: y.getArray('comments')
+   *     document: ydoc.getText('document')
+   *     comments: ydoc.getArray('comments')
    *   }
    *
    * @param {string} name
-   * @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
+   * @param {Type} TypeConstructor The constructor of the type definition. E.g. Y.Text, Y.Array, Y.Map, ...
+   * @return {InstanceType<Type>} The created type. Constructed with TypeConstructor
    *
    * @public
    */
-  get (name, TypeConstructor = AbstractType) {
+  get (name, TypeConstructor = /** @type {any} */ (AbstractType)) {
     const type = map.setIfUndefined(this.share, name, () => {
       // @ts-ignore
       const t = new TypeConstructor()
@@ -219,12 +237,12 @@ export class Doc extends Observable {
         t._length = type._length
         this.share.set(name, t)
         t._integrate(this, null)
-        return t
+        return /** @type {InstanceType<Type>} */ (t)
       } else {
         throw new Error(`Type with the name ${name} has already been defined with a different constructor`)
       }
     }
-    return type
+    return /** @type {InstanceType<Type>} */ (type)
   }
 
   /**
@@ -235,8 +253,7 @@ export class Doc extends Observable {
    * @public
    */
   getArray (name = '') {
-    // @ts-ignore
-    return this.get(name, YArray)
+    return /** @type {YArray<T>} */ (this.get(name, YArray))
   }
 
   /**
@@ -246,7 +263,6 @@ export class Doc extends Observable {
    * @public
    */
   getText (name = '') {
-    // @ts-ignore
     return this.get(name, YText)
   }
 
@@ -258,8 +274,17 @@ export class Doc extends Observable {
    * @public
    */
   getMap (name = '') {
-    // @ts-ignore
-    return this.get(name, YMap)
+    return /** @type {YMap<T>} */ (this.get(name, YMap))
+  }
+
+  /**
+   * @param {string} [name]
+   * @return {YXmlElement}
+   *
+   * @public
+   */
+  getXmlElement (name = '') {
+    return /** @type {YXmlElement<{[key:string]:string}>} */ (this.get(name, YXmlElement))
   }
 
   /**
@@ -269,7 +294,6 @@ export class Doc extends Observable {
    * @public
    */
   getXmlFragment (name = '') {
-    // @ts-ignore
     return this.get(name, YXmlFragment)
   }
 
@@ -313,24 +337,9 @@ export class Doc extends Observable {
         transaction.subdocsRemoved.add(this)
       }, null, true)
     }
-    this.emit('destroyed', [true])
+    // @ts-ignore
+    this.emit('destroyed', [true]) // DEPRECATED!
     this.emit('destroy', [this])
     super.destroy()
   }
-
-  /**
-   * @param {string} eventName
-   * @param {function(...any):any} f
-   */
-  on (eventName, f) {
-    super.on(eventName, f)
-  }
-
-  /**
-   * @param {string} eventName
-   * @param {function} f
-   */
-  off (eventName, f) {
-    super.off(eventName, f)
-  }
 }

src/utils/ID.js

@@ -1,4 +1,3 @@
-
 import { AbstractType } from '../internals.js' // eslint-disable-line
 
 import * as decoding from 'lib0/decoding'

src/utils/PermanentUserData.js

@@ -1,4 +1,3 @@
-
 import {
   YArray,
   YMap,

src/utils/RelativePosition.js

@@ -1,4 +1,3 @@
-
 import {
   writeID,
   readID,
@@ -9,6 +8,7 @@ import {
   createID,
   ContentType,
   followRedone,
+  getItem,
   ID, Doc, AbstractType // eslint-disable-line
 } from '../internals.js'
 
@@ -102,7 +102,7 @@ export const relativePositionToJSON = rpos => {
  *
  * @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), json.assoc == null ? 0 : json.assoc)
+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), json.assoc == null ? 0 : json.assoc)
 
 export class AbsolutePosition {
   /**
@@ -257,13 +257,24 @@ export const readRelativePosition = decoder => {
 export const decodeRelativePosition = uint8Array => readRelativePosition(decoding.createDecoder(uint8Array))
 
 /**
+ * Transform a relative position to an absolute position.
+ *
+ * If you want to share the relative position with other users, you should set
+ * `followUndoneDeletions` to false to get consistent results across all clients.
+ *
+ * When calculating the absolute position, we try to follow the "undone deletions". This yields
+ * better results for the user who performed undo. However, only the user who performed the undo
+ * will get the better results, the other users don't know which operations recreated a deleted
+ * range of content. There is more information in this ticket: https://github.com/yjs/yjs/issues/638
+ *
  * @param {RelativePosition} rpos
  * @param {Doc} doc
+ * @param {boolean} followUndoneDeletions - whether to follow undone deletions - see https://github.com/yjs/yjs/issues/638
  * @return {AbsolutePosition|null}
  *
  * @function
  */
-export const createAbsolutePositionFromRelativePosition = (rpos, doc) => {
+export const createAbsolutePositionFromRelativePosition = (rpos, doc, followUndoneDeletions = true) => {
   const store = doc.store
   const rightID = rpos.item
   const typeID = rpos.type
@@ -275,7 +286,7 @@ export const createAbsolutePositionFromRelativePosition = (rpos, doc) => {
     if (getState(store, rightID.client) <= rightID.clock) {
       return null
     }
-    const res = followRedone(store, rightID)
+    const res = followUndoneDeletions ? followRedone(store, rightID) : { item: getItem(store, rightID), diff: 0 }
     const right = res.item
     if (!(right instanceof Item)) {
       return null
@@ -299,7 +310,7 @@ export const createAbsolutePositionFromRelativePosition = (rpos, doc) => {
         // type does not exist yet
         return null
       }
-      const { item } = followRedone(store, typeID)
+      const { item } = followUndoneDeletions ? followRedone(store, typeID) : { item: getItem(store, typeID) }
       if (item instanceof Item && item.content instanceof ContentType) {
         type = item.content.type
       } else {

src/utils/Snapshot.js

@@ -1,4 +1,3 @@
-
 import {
   isDeleted,
   createDeleteSetFromStructStore,

src/utils/StructStore.js

@@ -1,4 +1,3 @@
-
 import {
   GC,
   splitItem,

src/utils/Transaction.js

@@ -1,4 +1,3 @@
-
 import {
   getState,
   writeStructsFromTransaction,
@@ -29,7 +28,8 @@ import { callAll } from 'lib0/function'
  * possible. Here is an example to illustrate the advantages of bundling:
  *
  * @example
- * const map = y.define('map', YMap)
+ * const ydoc = new Y.Doc()
+ * const map = ydoc.getMap('map')
  * // Log content when change is triggered
  * map.observe(() => {
  *   console.log('change triggered')
@@ -38,7 +38,7 @@ import { callAll } from 'lib0/function'
  * map.set('a', 0) // => "change triggered"
  * map.set('b', 0) // => "change triggered"
  * // When put in a transaction, it will trigger the log after the transaction:
- * y.transact(() => {
+ * ydoc.transact(() => {
  *   map.set('a', 1)
  *   map.set('b', 1)
  * }) // => "change triggered"
@@ -166,18 +166,29 @@ export const addChangedTypeToTransaction = (transaction, type, parentSub) => {
 /**
  * @param {Array<AbstractStruct>} structs
  * @param {number} pos
+ * @return {number} # of merged structs
  */
-const tryToMergeWithLeft = (structs, pos) => {
-  const left = structs[pos - 1]
-  const right = structs[pos]
-  if (left.deleted === right.deleted && left.constructor === right.constructor) {
-    if (left.mergeWith(right)) {
-      structs.splice(pos, 1)
-      if (right instanceof Item && right.parentSub !== null && /** @type {AbstractType<any>} */ (right.parent)._map.get(right.parentSub) === right) {
-        /** @type {AbstractType<any>} */ (right.parent)._map.set(right.parentSub, /** @type {Item} */ (left))
+const tryToMergeWithLefts = (structs, pos) => {
+  let right = structs[pos]
+  let left = structs[pos - 1]
+  let i = pos
+  for (; i > 0; right = left, left = structs[--i - 1]) {
+    if (left.deleted === right.deleted && left.constructor === right.constructor) {
+      if (left.mergeWith(right)) {
+        if (right instanceof Item && right.parentSub !== null && /** @type {AbstractType<any>} */ (right.parent)._map.get(right.parentSub) === right) {
+          /** @type {AbstractType<any>} */ (right.parent)._map.set(right.parentSub, /** @type {Item} */ (left))
+        }
+        continue
       }
     }
+    break
   }
+  const merged = pos - i
+  if (merged) {
+    // remove all merged structs from the array
+    structs.splice(pos + 1 - merged, merged)
+  }
+  return merged
 }
 
 /**
@@ -214,7 +225,7 @@ const tryGcDeleteSet = (ds, store, gcFilter) => {
  */
 const tryMergeDeleteSet = (ds, store) => {
   // try to merge deleted / gc'd items
-  // merge from right to left for better efficiecy and so we don't miss any merge targets
+  // merge from right to left for better efficiency and so we don't miss any merge targets
   ds.clients.forEach((deleteItems, client) => {
     const structs = /** @type {Array<GC|Item>} */ (store.clients.get(client))
     for (let di = deleteItems.length - 1; di >= 0; di--) {
@@ -224,9 +235,9 @@ const tryMergeDeleteSet = (ds, store) => {
       for (
         let si = mostRightIndexToCheck, struct = structs[si];
         si > 0 && struct.id.clock >= deleteItem.clock;
-        struct = structs[--si]
+        struct = structs[si]
       ) {
-        tryToMergeWithLeft(structs, si)
+        si -= 1 + tryToMergeWithLefts(structs, si)
       }
     }
   })
@@ -318,23 +329,25 @@ const cleanupTransactions = (transactionCleanups, i) => {
           const structs = /** @type {Array<GC|Item>} */ (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--) {
-            tryToMergeWithLeft(structs, i)
+          for (let i = structs.length - 1; i >= firstChangePos;) {
+            i -= 1 + tryToMergeWithLefts(structs, i)
           }
         }
       })
       // 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 (let i = 0; i < mergeStructs.length; i++) {
+      for (let i = mergeStructs.length - 1; i >= 0; i--) {
         const { client, clock } = mergeStructs[i].id
         const structs = /** @type {Array<GC|Item>} */ (store.clients.get(client))
         const replacedStructPos = findIndexSS(structs, clock)
         if (replacedStructPos + 1 < structs.length) {
-          tryToMergeWithLeft(structs, replacedStructPos + 1)
+          if (tryToMergeWithLefts(structs, replacedStructPos + 1) > 1) {
+            continue // no need to perform next check, both are already merged
+          }
         }
         if (replacedStructPos > 0) {
-          tryToMergeWithLeft(structs, replacedStructPos)
+          tryToMergeWithLefts(structs, replacedStructPos)
         }
       }
       if (!transaction.local && transaction.afterState.get(doc.clientID) !== transaction.beforeState.get(doc.clientID)) {

src/utils/UndoManager.js

@@ -10,12 +10,13 @@ import {
   getItemCleanStart,
   isDeleted,
   addToDeleteSet,
-  Transaction, Doc, Item, GC, DeleteSet, AbstractType // eslint-disable-line
+  YEvent, Transaction, Doc, Item, GC, DeleteSet, AbstractType // eslint-disable-line
 } from '../internals.js'
 
 import * as time from 'lib0/time'
 import * as array from 'lib0/array'
-import { Observable } from 'lib0/observable'
+import * as logging from 'lib0/logging'
+import { ObservableV2 } from 'lib0/observable'
 
 export class StackItem {
   /**
@@ -47,15 +48,10 @@ const clearUndoManagerStackItem = (tr, um, stackItem) => {
 /**
  * @param {UndoManager} undoManager
  * @param {Array<StackItem>} stack
- * @param {string} eventType
+ * @param {'undo'|'redo'} eventType
  * @return {StackItem?}
  */
 const popStackItem = (undoManager, stack, eventType) => {
-  /**
-   * Whether a change happened
-   * @type {StackItem?}
-   */
-  let result = null
   /**
    * Keep a reference to the transaction so we can fire the event with the changedParentTypes
    * @type {any}
@@ -64,7 +60,7 @@ const popStackItem = (undoManager, stack, eventType) => {
   const doc = undoManager.doc
   const scope = undoManager.scope
   transact(doc, transaction => {
-    while (stack.length > 0 && result === null) {
+    while (stack.length > 0 && undoManager.currStackItem === null) {
       const store = doc.store
       const stackItem = /** @type {StackItem} */ (stack.pop())
       /**
@@ -112,7 +108,7 @@ const popStackItem = (undoManager, stack, eventType) => {
           performedChange = true
         }
       }
-      result = performedChange ? stackItem : null
+      undoManager.currStackItem = performedChange ? stackItem : null
     }
     transaction.changed.forEach((subProps, type) => {
       // destroy search marker if necessary
@@ -122,11 +118,13 @@ const popStackItem = (undoManager, stack, eventType) => {
     })
     _tr = transaction
   }, undoManager)
-  if (result != null) {
+  const res = undoManager.currStackItem
+  if (res != null) {
     const changedParentTypes = _tr.changedParentTypes
-    undoManager.emit('stack-item-popped', [{ stackItem: result, type: eventType, changedParentTypes }, undoManager])
+    undoManager.emit('stack-item-popped', [{ stackItem: res, type: eventType, changedParentTypes, origin: undoManager }, undoManager])
+    undoManager.currStackItem = null
   }
-  return result
+  return res
 }
 
 /**
@@ -142,6 +140,14 @@ const popStackItem = (undoManager, stack, eventType) => {
  * @property {Doc} [doc] The document that this UndoManager operates on. Only needed if typeScope is empty.
  */
 
+/**
+ * @typedef {Object} StackItemEvent
+ * @property {StackItem} StackItemEvent.stackItem
+ * @property {any} StackItemEvent.origin
+ * @property {'undo'|'redo'} StackItemEvent.type
+ * @property {Map<AbstractType<YEvent<any>>,Array<YEvent<any>>>} StackItemEvent.changedParentTypes
+ */
+
 /**
  * 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
@@ -149,9 +155,9 @@ const popStackItem = (undoManager, stack, eventType) => {
  * 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'|'stack-cleared'|'stack-item-updated'>}
+ * @extends {ObservableV2<{'stack-item-added':function(StackItemEvent, UndoManager):void, 'stack-item-popped': function(StackItemEvent, UndoManager):void, 'stack-cleared': function({ undoStackCleared: boolean, redoStackCleared: boolean }):void, 'stack-item-updated': function(StackItemEvent, UndoManager):void }>}
  */
-export class UndoManager extends Observable {
+export class UndoManager extends ObservableV2 {
   /**
    * @param {AbstractType<any>|Array<AbstractType<any>>} typeScope Accepts either a single type, or an array of types
    * @param {UndoManagerOptions} options
@@ -169,6 +175,7 @@ export class UndoManager extends Observable {
      * @type {Array<AbstractType<any>>}
      */
     this.scope = []
+    this.doc = doc
     this.addToScope(typeScope)
     this.deleteFilter = deleteFilter
     trackedOrigins.add(this)
@@ -189,7 +196,12 @@ export class UndoManager extends Observable {
      */
     this.undoing = false
     this.redoing = false
-    this.doc = doc
+    /**
+     * The currently popped stack item if UndoManager.undoing or UndoManager.redoing
+     *
+     * @type {StackItem|null}
+     */
+    this.currStackItem = null
     this.lastChange = 0
     this.ignoreRemoteMapChanges = ignoreRemoteMapChanges
     this.captureTimeout = captureTimeout
@@ -243,6 +255,9 @@ export class UndoManager extends Observable {
           keepItem(item, true)
         }
       })
+      /**
+       * @type {[StackItemEvent, UndoManager]}
+       */
       const changeEvent = [{ stackItem: stack[stack.length - 1], origin: transaction.origin, type: undoing ? 'redo' : 'undo', changedParentTypes: transaction.changedParentTypes }, this]
       if (didAdd) {
         this.emit('stack-item-added', changeEvent)
@@ -263,6 +278,7 @@ export class UndoManager extends Observable {
     ytypes = array.isArray(ytypes) ? ytypes : [ytypes]
     ytypes.forEach(ytype => {
       if (this.scope.every(yt => yt !== ytype)) {
+        if (ytype.doc !== this.doc) logging.warn('[yjs#509] Not same Y.Doc') // use MultiDocUndoManager instead. also see https://github.com/yjs/yjs/issues/509
         this.scope.push(ytype)
       }
     })

src/utils/UpdateEncoder.js

@@ -1,4 +1,3 @@
-
 import * as error from 'lib0/error'
 import * as encoding from 'lib0/encoding'
 

src/utils/YEvent.js

@@ -1,4 +1,3 @@
-
 import {
   isDeleted,
   Item, AbstractType, Transaction, AbstractStruct // eslint-disable-line
@@ -6,6 +5,9 @@ import {
 
 import * as set from 'lib0/set'
 import * as array from 'lib0/array'
+import * as error from 'lib0/error'
+
+const errorComputeChanges = 'You must not compute changes after the event-handler fired.'
 
 /**
  * @template {AbstractType<any>} T
@@ -84,6 +86,9 @@ export class YEvent {
    */
   get keys () {
     if (this._keys === null) {
+      if (this.transaction.doc._transactionCleanups.length === 0) {
+        throw error.create(errorComputeChanges)
+      }
       const keys = new Map()
       const target = this.target
       const changed = /** @type Set<string|null> */ (this.transaction.changed.get(target))
@@ -167,6 +172,9 @@ export class YEvent {
   get changes () {
     let changes = this._changes
     if (changes === null) {
+      if (this.transaction.doc._transactionCleanups.length === 0) {
+        throw error.create(errorComputeChanges)
+      }
       const target = this.target
       const added = set.create()
       const deleted = set.create()
@@ -256,8 +264,8 @@ const getPathTo = (parent, child) => {
       let i = 0
       let c = /** @type {AbstractType<any>} */ (child._item.parent)._start
       while (c !== child._item && c !== null) {
-        if (!c.deleted) {
-          i++
+        if (!c.deleted && c.countable) {
+          i += c.length
         }
         c = c.right
       }

src/utils/encoding.js

@@ -1,4 +1,3 @@
-
 /**
  * @module encoding
  */
@@ -155,7 +154,7 @@ export const readClientsStructRefs = (decoder, doc) => {
           // @type {string|null}
           const struct = new Item(
             createID(client, clock),
-            null, // leftd
+            null, // left
             (info & binary.BIT8) === binary.BIT8 ? decoder.readLeftID() : null, // origin
             null, // right
             (info & binary.BIT7) === binary.BIT7 ? decoder.readRightID() : null, // right origin
@@ -179,7 +178,7 @@ export const readClientsStructRefs = (decoder, doc) => {
 
           const struct = new Item(
             createID(client, clock),
-            null, // leftd
+            null, // left
             origin, // origin
             null, // right
             rightOrigin, // right origin
@@ -251,7 +250,7 @@ const integrateStructs = (transaction, store, clientsStructRefs) => {
     return nextStructsTarget
   }
   let curStructsTarget = getNextStructTarget()
-  if (curStructsTarget === null && stack.length === 0) {
+  if (curStructsTarget === null) {
     return null
   }
 
@@ -371,7 +370,7 @@ export const writeStructsFromTransaction = (encoder, transaction) => writeClient
 /**
  * Read and apply a document update.
  *
- * This function has the same effect as `applyUpdate` but accepts an decoder.
+ * This function has the same effect as `applyUpdate` but accepts a decoder.
  *
  * @param {decoding.Decoder} decoder
  * @param {Doc} ydoc
@@ -452,7 +451,7 @@ export const readUpdateV2 = (decoder, ydoc, transactionOrigin, structDecoder = n
 /**
  * Read and apply a document update.
  *
- * This function has the same effect as `applyUpdate` but accepts an decoder.
+ * This function has the same effect as `applyUpdate` but accepts a decoder.
  *
  * @param {decoding.Decoder} decoder
  * @param {Doc} ydoc

src/utils/isParentOf.js

@@ -1,4 +1,3 @@
-
 import { AbstractType, Item } from '../internals.js' // eslint-disable-line
 
 /**

src/utils/logging.js

@@ -1,4 +1,3 @@
-
 import {
   AbstractType // eslint-disable-line
 } from '../internals.js'

src/utils/updates.js

@@ -1,4 +1,3 @@
-
 import * as binary from 'lib0/binary'
 import * as decoding from 'lib0/decoding'
 import * as encoding from 'lib0/encoding'

tests/compatibility.tests.js

@@ -1,4 +1,3 @@
-
 /**
  * Testing if encoding/decoding compatibility and integration compatiblity is given.
  * We expect that the document always looks the same, even if we upgrade the integration algorithm, or add additional encoding approaches.

tests/doc.tests.js

@@ -1,4 +1,3 @@
-
 import * as Y from '../src/index.js'
 import * as t from 'lib0/testing'
 

tests/relativePositions.tests.js

@@ -1,4 +1,3 @@
-
 import * as Y from '../src/index.js'
 import * as t from 'lib0/testing'
 
@@ -102,3 +101,25 @@ export const testRelativePositionAssociationDifference = tc => {
   t.assert(posRight != null && posRight.index === 2)
   t.assert(posLeft != null && posLeft.index === 1)
 }
+
+/**
+ * @param {t.TestCase} tc
+ */
+export const testRelativePositionWithUndo = tc => {
+  const ydoc = new Y.Doc()
+  const ytext = ydoc.getText()
+  ytext.insert(0, 'hello world')
+  const rpos = Y.createRelativePositionFromTypeIndex(ytext, 1)
+  const um = new Y.UndoManager(ytext)
+  ytext.delete(0, 6)
+  t.assert(Y.createAbsolutePositionFromRelativePosition(rpos, ydoc)?.index === 0)
+  um.undo()
+  t.assert(Y.createAbsolutePositionFromRelativePosition(rpos, ydoc)?.index === 1)
+  const posWithoutFollow = Y.createAbsolutePositionFromRelativePosition(rpos, ydoc, false)
+  console.log({ posWithoutFollow })
+  t.assert(Y.createAbsolutePositionFromRelativePosition(rpos, ydoc, false)?.index === 6)
+  const ydocClone = new Y.Doc()
+  Y.applyUpdate(ydocClone, Y.encodeStateAsUpdate(ydoc))
+  t.assert(Y.createAbsolutePositionFromRelativePosition(rpos, ydocClone)?.index === 6)
+  t.assert(Y.createAbsolutePositionFromRelativePosition(rpos, ydocClone, false)?.index === 6)
+}

tests/snapshot.tests.js

@@ -14,6 +14,21 @@ export const testBasic = _tc => {
   t.assert(restored.getText().toString() === 'world!')
 }
 
+/**
+ * @param {t.TestCase} _tc
+ */
+export const testBasicXmlAttributes = _tc => {
+  const ydoc = new Y.Doc({ gc: false })
+  const yxml = ydoc.getMap().set('el', new Y.XmlElement('div'))
+  const snapshot1 = Y.snapshot(ydoc)
+  yxml.setAttribute('a', '1')
+  const snapshot2 = Y.snapshot(ydoc)
+  yxml.setAttribute('a', '2')
+  t.compare(yxml.getAttributes(), { a: '2' })
+  t.compare(yxml.getAttributes(snapshot2), { a: '1' })
+  t.compare(yxml.getAttributes(snapshot1), {})
+}
+
 /**
  * @param {t.TestCase} _tc
  */

tests/testHelper.js

@@ -1,4 +1,3 @@
-
 import * as t from 'lib0/testing'
 import * as prng from 'lib0/prng'
 import * as encoding from 'lib0/encoding'
@@ -35,7 +34,7 @@ export const encV1 = {
   mergeUpdates: Y.mergeUpdates,
   applyUpdate: Y.applyUpdate,
   logUpdate: Y.logUpdate,
-  updateEventName: 'update',
+  updateEventName: /** @type {'update'} */ ('update'),
   diffUpdate: Y.diffUpdate
 }
 
@@ -44,7 +43,7 @@ export const encV2 = {
   mergeUpdates: Y.mergeUpdatesV2,
   applyUpdate: Y.applyUpdateV2,
   logUpdate: Y.logUpdateV2,
-  updateEventName: 'updateV2',
+  updateEventName: /** @type {'updateV2'} */ ('updateV2'),
   diffUpdate: Y.diffUpdateV2
 }
 

tests/undo-redo.tests.js

@@ -3,6 +3,46 @@ import { init } from './testHelper.js' // eslint-disable-line
 import * as Y from '../src/index.js'
 import * as t from 'lib0/testing'
 
+export const testInconsistentFormat = () => {
+  /**
+   * @param {Y.Doc} ydoc
+   */
+  const testYjsMerge = ydoc => {
+    const content = /** @type {Y.XmlText} */ (ydoc.get('text', Y.XmlText))
+    content.format(0, 6, { bold: null })
+    content.format(6, 4, { type: 'text' })
+    t.compare(content.toDelta(), [
+      {
+        attributes: { type: 'text' },
+        insert: 'Merge Test'
+      },
+      {
+        attributes: { type: 'text', italic: true },
+        insert: ' After'
+      }
+    ])
+  }
+  const initializeYDoc = () => {
+    const yDoc = new Y.Doc({ gc: false })
+
+    const content = /** @type {Y.XmlText} */ (yDoc.get('text', Y.XmlText))
+    content.insert(0, ' After', { type: 'text', italic: true })
+    content.insert(0, 'Test', { type: 'text' })
+    content.insert(0, 'Merge ', { type: 'text', bold: true })
+    return yDoc
+  }
+  {
+    const yDoc = initializeYDoc()
+    testYjsMerge(yDoc)
+  }
+  {
+    const initialYDoc = initializeYDoc()
+    const yDoc = new Y.Doc({ gc: false })
+    Y.applyUpdate(yDoc, Y.encodeStateAsUpdate(initialYDoc))
+    testYjsMerge(yDoc)
+  }
+}
+
 /**
  * @param {t.TestCase} tc
  */
@@ -675,3 +715,33 @@ export const testUndoDeleteInMap = (tc) => {
   undoManager.undo()
   t.compare(map0.toJSON(), { a: 'a' })
 }
+
+/**
+ * It should expose the StackItem being processed if undoing
+ *
+ * @param {t.TestCase} _tc
+ */
+export const testUndoDoingStackItem = async (_tc) => {
+  const doc = new Y.Doc()
+  const text = doc.getText('text')
+  const undoManager = new Y.UndoManager([text])
+  undoManager.on('stack-item-added', /** @param {any} event */ event => {
+    event.stackItem.meta.set('str', '42')
+  })
+  let metaUndo = /** @type {any} */ (null)
+  let metaRedo = /** @type {any} */ (null)
+  text.observe((event) => {
+    const /** @type {Y.UndoManager} */ origin = event.transaction.origin
+    if (origin === undoManager && origin.undoing) {
+      metaUndo = origin.currStackItem?.meta.get('str')
+    } else if (origin === undoManager && origin.redoing) {
+      metaRedo = origin.currStackItem?.meta.get('str')
+    }
+  })
+  text.insert(0, 'abc')
+  undoManager.undo()
+  undoManager.redo()
+  t.compare(metaUndo, '42', 'currStackItem is accessible while undoing')
+  t.compare(metaRedo, '42', 'currStackItem is accessible while redoing')
+  t.compare(undoManager.currStackItem, null, 'currStackItem is null after observe/transaction')
+}

tests/updates.tests.js

@@ -15,7 +15,7 @@ import * as object from 'lib0/object'
  * @property {function(Uint8Array):{from:Map<number,number>,to:Map<number,number>}} Enc.parseUpdateMeta
  * @property {function(Y.Doc):Uint8Array} Enc.encodeStateVector
  * @property {function(Uint8Array):Uint8Array} Enc.encodeStateVectorFromUpdate
- * @property {string} Enc.updateEventName
+ * @property {'update'|'updateV2'} Enc.updateEventName
  * @property {string} Enc.description
  * @property {function(Uint8Array, Uint8Array):Uint8Array} Enc.diffUpdate
  */
@@ -169,7 +169,7 @@ const checkUpdateCases = (ydoc, updates, enc, hasDeletes) => {
   // t.info('Target State: ')
   // enc.logUpdate(targetState)
 
-  cases.forEach((mergedUpdates, i) => {
+  cases.forEach((mergedUpdates) => {
     // t.info('State Case $' + i + ':')
     // enc.logUpdate(updates)
     const merged = new Y.Doc({ gc: false })
@@ -218,10 +218,10 @@ const checkUpdateCases = (ydoc, updates, enc, hasDeletes) => {
 }
 
 /**
- * @param {t.TestCase} tc
+ * @param {t.TestCase} _tc
  */
-export const testMergeUpdates1 = tc => {
-  encoders.forEach((enc, i) => {
+export const testMergeUpdates1 = _tc => {
+  encoders.forEach((enc) => {
     t.info(`Using encoder: ${enc.description}`)
     const ydoc = new Y.Doc({ gc: false })
     const updates = /** @type {Array<Uint8Array>} */ ([])
@@ -299,16 +299,16 @@ export const testMergePendingUpdates = tc => {
   Y.applyUpdate(yDoc5, update4)
   Y.applyUpdate(yDoc5, serverUpdates[4])
   // @ts-ignore
-  const update5 = Y.encodeStateAsUpdate(yDoc5) // eslint-disable-line
+  const _update5 = Y.encodeStateAsUpdate(yDoc5) // eslint-disable-line
 
   const yText5 = yDoc5.getText('textBlock')
   t.compareStrings(yText5.toString(), 'nenor')
 }
 
 /**
- * @param {t.TestCase} tc
+ * @param {t.TestCase} _tc
  */
-export const testObfuscateUpdates = tc => {
+export const testObfuscateUpdates = _tc => {
   const ydoc = new Y.Doc()
   const ytext = ydoc.getText('text')
   const ymap = ydoc.getMap('map')

tests/y-array.tests.js

@@ -330,6 +330,29 @@ export const testObserveDeepEventOrder = tc => {
   }
 }
 
+/**
+ * Correct index when computing event.path in observeDeep - https://github.com/yjs/yjs/issues/457
+ *
+ * @param {t.TestCase} _tc
+ */
+export const testObservedeepIndexes = _tc => {
+  const doc = new Y.Doc()
+  const map = doc.getMap()
+  // Create a field with the array as value
+  map.set('my-array', new Y.Array())
+  // Fill the array with some strings and our Map
+  map.get('my-array').push(['a', 'b', 'c', new Y.Map()])
+  /**
+   * @type {Array<any>}
+   */
+  let eventPath = []
+  map.observeDeep((events) => { eventPath = events[0].path })
+  // set a value on the map inside of our array
+  map.get('my-array').get(3).set('hello', 'world')
+  console.log(eventPath)
+  t.compare(eventPath, ['my-array', 3])
+}
+
 /**
  * @param {t.TestCase} tc
  */

tests/y-map.tests.js

@@ -8,6 +8,54 @@ import * as Y from '../src/index.js'
 import * as t from 'lib0/testing'
 import * as prng from 'lib0/prng'
 
+/**
+ * @param {t.TestCase} _tc
+ */
+export const testIterators = _tc => {
+  const ydoc = new Y.Doc()
+  /**
+   * @type {Y.Map<number>}
+   */
+  const ymap = ydoc.getMap()
+  // we are only checking if the type assumptions are correct
+  /**
+   * @type {Array<number>}
+   */
+  const vals = Array.from(ymap.values())
+  /**
+   * @type {Array<[string,number]>}
+   */
+  const entries = Array.from(ymap.entries())
+  /**
+   * @type {Array<string>}
+   */
+  const keys = Array.from(ymap.keys())
+  console.log(vals, entries, keys)
+}
+
+/**
+ * Computing event changes after transaction should result in an error. See yjs#539
+ *
+ * @param {t.TestCase} _tc
+ */
+export const testMapEventError = _tc => {
+  const doc = new Y.Doc()
+  const ymap = doc.getMap()
+  /**
+   * @type {any}
+   */
+  let event = null
+  ymap.observe((e) => {
+    event = e
+  })
+  t.fails(() => {
+    t.info(event.keys)
+  })
+  t.fails(() => {
+    t.info(event.keys)
+  })
+}
+
 /**
  * @param {t.TestCase} tc
  */

tests/y-text.tests.js

@@ -1746,6 +1746,27 @@ export const testBasicFormat = tc => {
   compare(users)
 }
 
+/**
+ * @param {t.TestCase} tc
+ */
+export const testFalsyFormats = tc => {
+  const { users, text0 } = init(tc, { users: 2 })
+  let delta
+  text0.observe(event => {
+    delta = event.delta
+  })
+  text0.insert(0, 'abcde', { falsy: false })
+  t.compare(text0.toDelta(), [{ insert: 'abcde', attributes: { falsy: false } }])
+  t.compare(delta, [{ insert: 'abcde', attributes: { falsy: false } }])
+  text0.format(1, 3, { falsy: true })
+  t.compare(text0.toDelta(), [{ insert: 'a', attributes: { falsy: false } }, { insert: 'bcd', attributes: { falsy: true } }, { insert: 'e', attributes: { falsy: false } }])
+  t.compare(delta, [{ retain: 1 }, { retain: 3, attributes: { falsy: true } }])
+  text0.format(2, 1, { falsy: false })
+  t.compare(text0.toDelta(), [{ insert: 'a', attributes: { falsy: false } }, { insert: 'b', attributes: { falsy: true } }, { insert: 'c', attributes: { falsy: false } }, { insert: 'd', attributes: { falsy: true } }, { insert: 'e', attributes: { falsy: false } }])
+  t.compare(delta, [{ retain: 2 }, { retain: 1, attributes: { falsy: false } }])
+  compare(users)
+}
+
 /**
  * @param {t.TestCase} _tc
  */

tests/y-xml.tests.js

@@ -189,7 +189,6 @@ export const testClone = _tc => {
   const third = new Y.XmlElement('p')
   yxml.push([first, second, third])
   t.compareArrays(yxml.toArray(), [first, second, third])
-
   const cloneYxml = yxml.clone()
   ydoc.getArray('copyarr').insert(0, [cloneYxml])
   t.assert(cloneYxml.length === 3)
@@ -210,3 +209,15 @@ export const testFormattingBug = _tc => {
   yxml.applyDelta(delta)
   t.compare(yxml.toDelta(), delta)
 }
+
+/**
+ * @param {t.TestCase} _tc
+ */
+export const testElement = _tc => {
+  const ydoc = new Y.Doc()
+  const yxmlel = ydoc.getXmlElement()
+  const text1 = new Y.XmlText('text1')
+  const text2 = new Y.XmlText('text2')
+  yxmlel.insert(0, [text1, text2])
+  t.compareArrays(yxmlel.toArray(), [text1, text2])
+}