13.6.0-2

fix various tests
13.6.0-1
2021-12-08 16:12:11 +01:00 · 2021-12-08 16:10:49 +01:00 · 2021-12-07 13:54:22 +01:00 · 2021-12-07 13:53:28 +01:00 · 2021-12-07 12:42:32 +01:00 · 2021-12-07 12:41:40 +01:00
30 changed files with 1888 additions and 5237 deletions
--- a/INTERNALS.md
+++ b/INTERNALS.md
@@ -152,8 +152,8 @@ concepts that can be used to create a custom network protocol:
 an incremental document updates that allows clients to sync with each other.
 The update object is an 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
+* `state vector`: A state vector defines the know state of each user (a set of
+  tubles `(client, clock)`). This object is also efficiently encoded as a
 Uint8Array.

 The client can ask a remote client for missing document updates by sending
@@ -168,7 +168,7 @@ An implementation of the syncing process is in
 ## Snapshots

 A snapshot can be used to restore an old document state. It is a `state vector`
-\+ `delete set`. A client can restore an old document state by iterating through
+\+ `delete set`. I client can restore an old document state by iterating through
 the sequence CRDT and ignoring all Items that have an `id.clock >
 stateVector[id.client].clock`. Instead of using `item.deleted` the client will
 use the delete set to find out if an item was deleted or not.
--- a/README.md
+++ b/README.md
@@ -25,16 +25,30 @@ build collaborative or distributed applications ping us at
 <yjs@tag1consulting.com>. Otherwise you can find help on our
 [discussion board](https://discuss.yjs.dev).

-## Sponsorship
+## Sponsors

-Please contribute to the project financially if your company relies on Yjs.
-Support the project and receive more attention on your tickets.
-[![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)
+I'm currently looking for sponsors that allow me to be less dependent on
+contracting work. These awesome backers already fund further development of
+Yjs:
+
+[![davidhq](https://github.com/davidhq.png?size=60)](https://github.com/davidhq)
+[![Ifiok Jr.](https://github.com/ifiokjr.png?size=60)](https://github.com/ifiokjr)
+[![Burke Libbey](https://github.com/burke.png?size=60)](https://github.com/burke)
+[![Beni Cherniavsky-Paskin](https://github.com/cben.png?size=60)](https://github.com/cben)
+[![Tom Moor](https://github.com/tommoor.png?size=60)](https://github.com/tommoor)
+[![Michael Meyers](https://github.com/michaelemeyers.png?size=60)](https://github.com/michaelemeyers)
+[![Cristiano Benjamin](https://github.com/csbenjamin.png?size=60)](https://github.com/csbenjamin)
+[![Braden](https://github.com/AdventureBeard.png?size=60)](https://github.com/AdventureBeard)
+[![nimbuswebinc](https://nimbusweb.me/new-style-img/note-icon.svg)](https://github.com/nimbuswebinc)
+[![JourneyApps](https://github.com/journeyapps.png?size=60)](https://github.com/journeyapps)
+[![Adam Brunnmeier](https://github.com/adabru.png?size=60)](https://github.com/adabru)
+[![Nathanael Anderson](https://github.com/NathanaelA.png?size=60)](https://github.com/NathanaelA)
+[<img src="https://room.sh/img/icons/android-chrome-192x192.png" height="60px" />](https://room.sh/)
+
+Sponsorship also comes with special perks! [![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)

 ## Who is using Yjs

-* [PRSM](https://prsm.uk/) Collaborative mind-mapping and system visualisation. *[(source)](https://github.com/micrology/prsm)*
-* [Dynaboard](https://dynaboard.com/) Build web apps collaboratively. :star2:
 * [Serenity Notes](https://www.serenity.re/en/notes) End-to-end encrypted
  collaborative notes app.
 * [Relm](https://www.relm.us/) A collaborative gameworld for teamwork and
@@ -42,11 +56,15 @@ Support the project and receive more attention on your tickets.
 * [Input](https://input.com/) A collaborative note taking app. :star2:
 * [Room.sh](https://room.sh/) A meeting application with integrated
  collaborative drawing, editing, and coding tools. :star:
+* [https://coronavirustechhandbook.com/](https://coronavirustechhandbook.com/)
+  A collaborative wiki that is edited by thousands of different people to work
+  on a rapid and sophisticated response to the coronavirus outbreak and
+  subsequent impacts. :star:
 * [Nimbus Note](https://nimbusweb.me/note.php) A note-taking app designed by
  Nimbus Web.
 * [JoeDocs](https://joedocs.com/) An open collaborative wiki.
-* [Pluxbox RadioManager](https://getradiomanager.com/) A web-based app to
-  collaboratively organize radio broadcasts. :star:
+* [Pluxbox RadioManager](https://pluxbox.com/) A web-based app to
+  collaboratively organize radio broadcasts.
 * [Alldone](https://alldone.app/) A next-gen project management and
  collaboration platform.

@@ -81,7 +99,6 @@ 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) |
 | [valtio](https://github.com/pmndrs/valtio) |  | [valtio-yjs](https://github.com/dai-shi/valtio-yjs) | [demo](https://codesandbox.io/s/valtio-yjs-demo-ox3iy) |
-| React / Vue / Svelte / MobX | | [SyncedStore](https://syncedstore.org) | [demo](https://syncedstore.org/docs/react) |

 ### Providers

@@ -110,12 +127,6 @@ leveldb database.
 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/marcopolo/y-libp2p">y-libp2p</a></dt>
-  <dd>
-Uses <a href="https://libp2p.io/">libp2p</a> to propagate updates via
-<a href="https://github.com/libp2p/specs/tree/master/pubsub/gossipsub">GossipSub</a>.
-Also includes a peer-sync mechanism to catch up on missed updates.
  </dd>
  <dt><a href="https://github.com/yjs/y-dat">y-dat</a></dt>
  <dd>
@@ -123,15 +134,6 @@ Also includes a peer-sync mechanism to catch up on missed updates.
 <a href="https://github.com/kappa-db/multifeed">multifeed</a>. Each client has
 an append-only log of CRDT local updates (hypercore). Multifeed manages and sync
 hypercores and y-dat listens to changes and applies them to the Yjs document.
-</dd>
-  <dt><a href="https://github.com/yousefED/matrix-crdt">Matrix-CRDT</a></dt>
-  <dd>
-Use <a href="https://www.matrix.org">Matrix</a> as an off-the-shelf backend for
-Yjs by using the <a href="https://github.com/yousefED/matrix-crdt">MatrixProvider</a>.
-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>
 </dl>

@@ -710,7 +712,7 @@ Y.applyUpdate(ydoc1, diff2)
 Y.applyUpdate(ydoc2, diff1)
 ```

-#### Example: Syncing clients without loading the Y.Doc
+### Example: Syncing clients without loading the Y.Doc

 It is possible to sync clients and compute delta updates without loading the Yjs
 document to memory. Yjs exposes an API to compute the differences directly on the
@@ -734,17 +736,6 @@ currentState1 = Y.mergeUpdates([currentState1, diff2])
 currentState1 = Y.mergeUpdates([currentState1, diff1])
 ```

-#### 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.
-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`.
-
-#### Update API
-
 <dl>
  <b><code>Y.applyUpdate(Y.Doc, update:Uint8Array, [transactionOrigin:any])</code></b>
  <dd>
@@ -777,14 +768,6 @@ Encode the missing differences to another update message. This function works
 similarly to <code>Y.encodeStateAsUpdate(ydoc, stateVector)</code> but works
 on updates instead.
  </dd>
-  <b><code>convertUpdateFormatV1ToV2</code></b>
-  <dd>
-Convert V1 update format to the V2 update format.
-  </dd>
-  <b><code>convertUpdateFormatV2ToV1</code></b>
-  <dd>
-Convert V2 update format to the V1 update format.
-  </dd>
 </dl>

 ### Relative Positions
@@ -971,7 +954,7 @@ undoManager.on('stack-item-popped', event => {

 *Conflict-free replicated data types* (CRDT) for collaborative editing are an
 alternative approach to *operational transformation* (OT). A very simple
-differentiation between the two approaches is that OT attempts to transform
+differenciation between the two approaches is that OT attempts to transform
 index positions to ensure convergence (all clients end up with the same
 content), while CRDTs use mathematical models that usually do not involve index
 transformations, like linked lists. OT is currently the de-facto standard for
--- a/package-lock.json
+++ b/package-lock.json
--- a/package.json
+++ b/package.json
@@ -1,6 +1,6 @@
 {
  "name": "yjs",
-  "version": "13.5.28",
+  "version": "13.6.0-2",
  "description": "Shared Editing Library",
  "main": "./dist/yjs.cjs",
  "module": "./dist/yjs.mjs",
@@ -19,10 +19,11 @@
    "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 && http-server ./docs/",
-    "preversion": "npm run lint && PRODUCTION=1 npm run dist && npm run docs && node ./dist/tests.cjs --repetition-time 1000 && test -e dist/src/index.d.ts && test -e dist/yjs.cjs && test -e dist/yjs.cjs",
+    "preversion": "npm run lint && PRODUCTION=1 npm run dist && npm run docs && test -e dist/src/index.d.ts && test -e dist/yjs.cjs && test -e dist/yjs.cjs",
    "debug": "concurrently 'http-server -o test.html' 'npm run watch'",
    "trace-deopt": "clear && rollup -c  && node --trace-deopt dist/test.cjs",
-    "trace-opt": "clear && rollup -c  && node --trace-opt dist/test.cjs"
+    "trace-opt": "clear && rollup -c  && node --trace-opt dist/test.cjs",
+    "postinstall": "node ./sponsor-y.js"
  },
  "exports": {
    ".": {
--- a/sponsor-y.js
+++ b/sponsor-y.js
@@ -0,0 +1,12 @@
+
+try {
+  const log = require('lib0/dist/logging.cjs')
+
+  log.print()
+  log.print(log.BOLD, log.GREEN, log.BOLD, 'Thank you for using Yjs ', log.RED, '❤\n')
+  log.print(
+    log.GREY,
+    'The project has grown considerably in the past year. Too much for me to maintain\nin my spare time. Several companies built their products with Yjs.\nYet, this project receives very little funding. Yjs is far from done. I want to\ncreate more awesome extensions and work on the growing number of open issues.\n', log.BOLD, 'Dear user, the future of this project entirely depends on you.\n')
+  log.print(log.BLUE, log.BOLD, 'Please start funding the project now: https://github.com/sponsors/dmonad \n')
+  log.print(log.GREY, '(This message will be removed when I achieved my funding goal)\n\n')
+} catch (e) { }
--- a/src/index.js
+++ b/src/index.js
@@ -67,8 +67,6 @@ export {
  decodeStateVector,
  logUpdate,
  logUpdateV2,
-  decodeUpdate,
-  decodeUpdateV2,
  relativePositionToJSON,
  isDeleted,
  isParentOf,
@@ -87,16 +85,12 @@ export {
  encodeRelativePosition,
  decodeRelativePosition,
  diffUpdate,
-  diffUpdateV2,
-  convertUpdateFormatV1ToV2,
-  convertUpdateFormatV2ToV1
+  diffUpdateV2
 } from './internals.js'

 const glo = /** @type {any} */ (typeof window !== 'undefined'
  ? window
-  // @ts-ignore
  : typeof global !== 'undefined' ? global : {})
-
 const importIdentifier = '__ $YJS$ __'

 if (glo[importIdentifier] === true) {
--- a/src/internals.js
+++ b/src/internals.js
@@ -8,6 +8,7 @@ export * from './utils/encoding.js'
 export * from './utils/EventHandler.js'
 export * from './utils/ID.js'
 export * from './utils/isParentOf.js'
+export * from './utils/ListIterator.js'
 export * from './utils/logging.js'
 export * from './utils/PermanentUserData.js'
 export * from './utils/RelativePosition.js'
@@ -38,6 +39,7 @@ export * from './structs/ContentFormat.js'
 export * from './structs/ContentJSON.js'
 export * from './structs/ContentAny.js'
 export * from './structs/ContentString.js'
+export * from './structs/ContentMove.js'
 export * from './structs/ContentType.js'
 export * from './structs/Item.js'
 export * from './structs/Skip.js'
--- a/src/structs/ContentMove.js
+++ b/src/structs/ContentMove.js
@@ -0,0 +1,286 @@
+
+import * as error from 'lib0/error'
+import * as decoding from 'lib0/decoding'
+import * as encoding from 'lib0/encoding'
+import * as math from 'lib0/math'
+import {
+  AbstractType, ContentType, RelativePosition, UpdateDecoderV1, UpdateDecoderV2, UpdateEncoderV1, UpdateEncoderV2, Transaction, Item, StructStore, getItem, getItemCleanStart, getItemCleanEnd // eslint-disable-line
+} from '../internals.js'
+import { decodeRelativePosition, encodeRelativePosition } from 'yjs'
+
+/**
+ * @param {ContentMove} moved
+ * @param {Transaction} tr
+ * @return {{ start: Item, end: Item | null }} $start (inclusive) is the beginning and $end (exclusive) is the end of the moved area
+ */
+export const getMovedCoords = (moved, tr) => {
+  let start // this (inclusive) is the beginning of the moved area
+  let end // this (exclusive) is the first item after start that is not part of the moved area
+  if (moved.start.item) {
+    if (moved.start.assoc < 0) {
+      start = getItemCleanEnd(tr, moved.start.item)
+      start = start.right
+    } else {
+      start = getItemCleanStart(tr, moved.start.item)
+    }
+  } else if (moved.start.tname != null) {
+    start = tr.doc.get(moved.start.tname)._start
+  } else if (moved.start.type) {
+    start = /** @type {ContentType} */ (getItem(tr.doc.store, moved.start.type).content).type._start
+  } else {
+    error.unexpectedCase()
+  }
+  if (moved.end.item) {
+    if (moved.end.assoc < 0) {
+      end = getItemCleanEnd(tr, moved.end.item)
+      end = end.right
+    } else {
+      end = getItemCleanStart(tr, moved.end.item)
+    }
+  } else {
+    end = null
+  }
+  return { start: /** @type {Item} */ (start), end }
+}
+
+/**
+ * @todo remove this if not needed
+ *
+ * @param {ContentMove} moved
+ * @param {Item} movedItem
+ * @param {Transaction} tr
+ * @param {function(Item):void} cb
+ */
+export const iterateMoved = (moved, movedItem, tr, cb) => {
+  /**
+   * @type {{ start: Item | null, end: Item | null }}
+   */
+  let { start, end } = getMovedCoords(moved, tr)
+  while (start !== end && start != null) {
+    if (!start.deleted) {
+      if (start.moved === movedItem) {
+        if (start.content.constructor === ContentMove) {
+          iterateMoved(start.content, start, tr, cb)
+        } else {
+          cb(start)
+        }
+      }
+    }
+    start = start.right
+  }
+}
+
+/**
+ * @param {ContentMove} moved
+ * @param {Item} movedItem
+ * @param {Set<Item>} trackedMovedItems
+ * @param {Transaction} tr
+ * @return {boolean} true if there is a loop
+ */
+export const findMoveLoop = (moved, movedItem, trackedMovedItems, tr) => {
+  if (trackedMovedItems.has(movedItem)) {
+    return true
+  }
+  trackedMovedItems.add(movedItem)
+  /**
+   * @type {{ start: Item | null, end: Item | null }}
+   */
+  let { start, end } = getMovedCoords(moved, tr)
+  while (start !== end && start != null) {
+    if (start.deleted && start.moved === movedItem && start.content.constructor === ContentMove) {
+      if (findMoveLoop(start.content, start, trackedMovedItems, tr)) {
+        return true
+      }
+    }
+    start = start.right
+  }
+  return false
+}
+
+/**
+ * @private
+ */
+export class ContentMove {
+  /**
+   * @param {RelativePosition} start
+   * @param {RelativePosition} end
+   * @param {number} priority if we want to move content that is already moved, we need to assign a higher priority to this move operation.
+   */
+  constructor (start, end, priority) {
+    this.start = start
+    this.end = end
+    this.priority = priority
+    /**
+     * We store which Items+ContentMove we override. Once we delete
+     * this ContentMove, we need to re-integrate the overridden items.
+     *
+     * This representation can be improved if we ever run into memory issues because of too many overrides.
+     * Ideally, we should probably just re-iterate the document and re-integrate all moved items.
+     * This is fast enough and reduces memory footprint significantly.
+     *
+     * @type {Set<Item>}
+     */
+    this.overrides = new Set()
+  }
+
+  /**
+   * @return {number}
+   */
+  getLength () {
+    return 1
+  }
+
+  /**
+   * @return {Array<any>}
+   */
+  getContent () {
+    return [null]
+  }
+
+  /**
+   * @return {boolean}
+   */
+  isCountable () {
+    return false
+  }
+
+  /**
+   * @return {ContentMove}
+   */
+  copy () {
+    return new ContentMove(this.start, this.end, this.priority)
+  }
+
+  /**
+   * @param {number} offset
+   * @return {ContentMove}
+   */
+  splice (offset) {
+    return this
+  }
+
+  /**
+   * @param {ContentMove} right
+   * @return {boolean}
+   */
+  mergeWith (right) {
+    return false
+  }
+
+  /**
+   * @param {Transaction} transaction
+   * @param {Item} item
+   */
+  integrate (transaction, item) {
+    /** @type {AbstractType<any>} */ (item.parent)._searchMarker = []
+    /**
+     * @type {{ start: Item | null, end: Item | null }}
+     */
+    let { start, end } = getMovedCoords(this, transaction)
+    let maxPriority = 0
+    // If this ContentMove was created locally, we set prio = -1. This indicates
+    // that we want to set prio to the current prio-maximum of the moved range.
+    const adaptPriority = this.priority < 0
+    while (start !== end && start != null) {
+      if (!start.deleted) {
+        const currMoved = start.moved
+        const nextPrio = currMoved ? /** @type {ContentMove} */ (currMoved.content).priority : -1
+        if (currMoved === null || adaptPriority || nextPrio < this.priority || currMoved.id.client < item.id.client || (currMoved.id.client === item.id.client && currMoved.id.clock < item.id.clock)) {
+          if (currMoved !== null) {
+            this.overrides.add(currMoved)
+          }
+          maxPriority = math.max(maxPriority, nextPrio)
+          // was already moved
+          if (start.moved && !transaction.prevMoved.has(start)) {
+            // we need to know which item previously moved an item
+            transaction.prevMoved.set(start, start.moved)
+          }
+          start.moved = item
+        } else {
+          /** @type {ContentMove} */ (currMoved.content).overrides.add(item)
+        }
+      }
+      start = start.right
+    }
+    if (adaptPriority) {
+      this.priority = maxPriority + 1
+    }
+  }
+
+  /**
+   * @param {Transaction} transaction
+   * @param {Item} item
+   */
+  delete (transaction, item) {
+    /**
+     * @type {{ start: Item | null, end: Item | null }}
+     */
+    let { start, end } = getMovedCoords(this, transaction)
+    while (start !== end && start != null) {
+      if (start.moved === item) {
+        start.moved = null
+      }
+      start = start.right
+    }
+    /**
+     * @param {Item} reIntegrateItem
+     */
+    const reIntegrate = reIntegrateItem => {
+      const content = /** @type {ContentMove} */ (reIntegrateItem.content)
+      if (reIntegrateItem.deleted) {
+        // potentially we can integrate the items that reIntegrateItem overrides
+        content.overrides.forEach(reIntegrate)
+      } else {
+        content.integrate(transaction, reIntegrateItem)
+      }
+    }
+    this.overrides.forEach(reIntegrate)
+  }
+
+  /**
+   * @param {StructStore} store
+   */
+  gc (store) {}
+
+  /**
+   * @param {UpdateEncoderV1 | UpdateEncoderV2} encoder
+   * @param {number} offset
+   */
+  write (encoder, offset) {
+    const isCollapsed = this.isCollapsed()
+    encoding.writeUint8(encoder.restEncoder, isCollapsed ? 1 : 0)
+    encoder.writeBuf(encodeRelativePosition(this.start))
+    if (!isCollapsed) {
+      encoder.writeBuf(encodeRelativePosition(this.end))
+    }
+    encoding.writeVarUint(encoder.restEncoder, this.priority)
+  }
+
+  /**
+   * @return {number}
+   */
+  getRef () {
+    return 11
+  }
+
+  isCollapsed () {
+    return this.start.item === this.end.item && this.start.item !== null
+  }
+}
+
+/**
+ * @private
+ * @todo use binary encoding option for start & end relpos's
+ *
+ * @param {UpdateDecoderV1 | UpdateDecoderV2} decoder
+ * @return {ContentMove}
+ */
+export const readContentMove = decoder => {
+  const isCollapsed = decoding.readUint8(decoder.restDecoder) === 1
+  const start = decodeRelativePosition(decoder.readBuf())
+  const end = isCollapsed ? start.clone() : decodeRelativePosition(decoder.readBuf())
+  if (isCollapsed) {
+    end.assoc = -1
+  }
+  return new ContentMove(start, end, decoding.readVarUint(decoder.restDecoder))
+}
--- a/src/structs/ContentType.js
+++ b/src/structs/ContentType.js
@@ -39,7 +39,7 @@ export const YXmlTextRefID = 6
 */
 export class ContentType {
  /**
-   * @param {AbstractType<any>} type
+   * @param {AbstractType<YEvent>} type
   */
  constructor (type) {
    /**
@@ -109,7 +109,7 @@ export class ContentType {
      if (!item.deleted) {
        item.delete(transaction)
      } else {
-        // This will be gc'd later and we want to merge it if possible
+        // 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
--- a/src/structs/Item.js
+++ b/src/structs/Item.js
@@ -21,13 +21,14 @@ import {
  createID,
  readContentFormat,
  readContentType,
+  readContentMove,
  addChangedTypeToTransaction,
-  isDeleted,
-  DeleteSet, UpdateDecoderV1, UpdateDecoderV2, UpdateEncoderV1, UpdateEncoderV2, ContentType, ContentDeleted, StructStore, ID, AbstractType, Transaction // eslint-disable-line
+  UpdateDecoderV1, UpdateDecoderV2, UpdateEncoderV1, UpdateEncoderV2, ContentType, ContentDeleted, StructStore, ID, AbstractType, Transaction // eslint-disable-line
 } from '../internals.js'

 import * as error from 'lib0/error'
 import * as binary from 'lib0/binary'
+import { ContentMove } from './ContentMove.js'

 /**
 * @todo This should return several items
@@ -117,6 +118,12 @@ export const splitItem = (transaction, leftItem, diff) => {
    /** @type {AbstractType<any>} */ (rightItem.parent)._map.set(rightItem.parentSub, rightItem)
  }
  leftItem.length = diff
+  if (leftItem.moved) {
+    const m = transaction.prevMoved.get(leftItem)
+    if (m) {
+      transaction.prevMoved.set(rightItem, m)
+    }
+  }
  return rightItem
 }

@@ -126,7 +133,7 @@ export const splitItem = (transaction, leftItem, diff) => {
 * @param {Transaction} transaction The Yjs instance.
 * @param {Item} item
 * @param {Set<Item>} redoitems
- * @param {DeleteSet} itemsToDelete
+ * @param {Array<Item>} itemsToDelete
 *
 * @return {Item|null}
 *
@@ -144,27 +151,42 @@ export const redoItem = (transaction, item, redoitems, itemsToDelete) => {
  /**
   * @type {Item|null}
   */
-  let left = null
+  let left
  /**
   * @type {Item|null}
   */
  let right
-  // make sure that parent is redone
-  if (parentItem !== null && parentItem.deleted === true) {
-    // try to undo parent if it will be undone anyway
-    if (parentItem.redone === null && (!redoitems.has(parentItem) || redoItem(transaction, parentItem, redoitems, itemsToDelete) === null)) {
-      return null
-    }
-    while (parentItem.redone !== null) {
-      parentItem = getItemCleanStart(transaction, parentItem.redone)
-    }
-  }
-  const parentType = parentItem === null ? /** @type {AbstractType<any>} */ (item.parent) : /** @type {ContentType} */ (parentItem.content).type
-
  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 !== ownClientID) {
+        // 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} */ (/** @type {AbstractType<any>} */ (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, itemsToDelete) === 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) {
      /**
@@ -196,32 +218,10 @@ export const redoItem = (transaction, item, redoitems, itemsToDelete) => {
      }
      right = right.right
    }
-  } else {
-    right = null
-    if (item.right) {
-      left = item
-      // Iterate right while right is in itemsToDelete
-      // If it is intended to delete right while item is redone, we can expect that item should replace right.
-      while (left !== null && left.right !== null && isDeleted(itemsToDelete, left.right.id)) {
-        left = left.right
-      }
-      // follow redone
-      // trace redone until parent matches
-      while (left !== null && left.redone !== null) {
-        left = getItemCleanStart(transaction, left.redone)
-      }
-      // check wether we were allowed to follow right (indicating that originally this op was replaced by another item)
-      if (left === null || /** @type {AbstractType<any>} */ (left.parent)._item !== parentItem) {
-        // invalid parent; should never happen
-        return null
-      }
-      if (left && left.right !== null) {
-        // It is not possible to redo this item because it conflicts with a
-        // change from another client
-        return null
-      }
-    } else {
-      left = parentType._map.get(item.parentSub) || null
+    // Iterate right while right is in itemsToDelete
+    // If it is intended to delete right while item is redone, we can expect that item should replace right.
+    while (left !== null && left.right !== null && left.right !== right && itemsToDelete.findIndex(d => d === /** @type {Item} */ (left).right) >= 0) {
+      left = left.right
    }
  }
  const nextClock = getState(store, ownClientID)
@@ -230,7 +230,7 @@ export const redoItem = (transaction, item, redoitems, itemsToDelete) => {
    nextId,
    left, left && left.lastId,
    right, right && right.id,
-    parentType,
+    parentItem === null ? item.parent : /** @type {ContentType} */ (parentItem.content).type,
    item.parentSub,
    item.content.copy()
  )
@@ -289,11 +289,18 @@ export class Item extends AbstractStruct {
     */
    this.parentSub = parentSub
    /**
-     * If this type's effect is redone this type refers to the type that undid
+     * If this type's effect is reundone this type refers to the type-id that undid
     * this operation.
+     *
     * @type {ID | null}
     */
    this.redone = null
+    /**
+     * This property is reused by the moved prop. In this case this property refers to an Item.
+     *
+     * @type {Item | null}
+     */
+    this.moved = null
    /**
     * @type {AbstractContent}
     */
@@ -375,11 +382,21 @@ export class Item extends AbstractStruct {
    if (this.parent && this.parent.constructor === ID && this.id.client !== this.parent.client && this.parent.clock >= getState(store, this.parent.client)) {
      return this.parent.client
    }
+    if (this.content.constructor === ContentMove) {
+      const c = /** @type {ContentMove} */ (this.content)
+      const start = c.start.item
+      const end = c.isCollapsed() ? null : c.end.item
+      if (start && start.clock >= getState(store, start.client)) {
+        return start.client
+      }
+      if (end && end.clock >= getState(store, end.client)) {
+        return end.client
+      }
+    }

    // We have all missing ids, now find the items
-
    if (this.origin) {
-      this.left = getItemCleanEnd(transaction, store, this.origin)
+      this.left = getItemCleanEnd(transaction, this.origin)
      this.origin = this.left.lastId
    }
    if (this.rightOrigin) {
@@ -407,6 +424,7 @@ export class Item extends AbstractStruct {
        this.parent = /** @type {ContentType} */ (parentItem.content).type
      }
    }
+
    return null
  }

@@ -417,7 +435,7 @@ export class Item extends AbstractStruct {
  integrate (transaction, offset) {
    if (offset > 0) {
      this.id.clock += offset
-      this.left = getItemCleanEnd(transaction, transaction.doc.store, createID(this.id.client, this.id.clock - 1))
+      this.left = getItemCleanEnd(transaction, createID(this.id.client, this.id.clock - 1))
      this.origin = this.left.lastId
      this.content = this.content.splice(offset)
      this.length -= offset
@@ -577,21 +595,22 @@ export class Item extends AbstractStruct {
      this.deleted === right.deleted &&
      this.redone === null &&
      right.redone === null &&
+      this.moved === right.moved &&
      this.content.constructor === right.content.constructor &&
      this.content.mergeWith(right.content)
    ) {
-      const searchMarker = /** @type {AbstractType<any>} */ (this.parent)._searchMarker
-      if (searchMarker) {
-        searchMarker.forEach(marker => {
-          if (marker.p === right) {
-            // right is going to be "forgotten" so we need to update the marker
-            marker.p = this
-            // adjust marker index
-            if (!this.deleted && this.countable) {
-              marker.index -= this.length
+      if (right.marker) {
+        // Right will be "forgotten", so we delete all
+        // search markers that reference right.
+        const searchMarker = /** @type {AbstractType<any>} */ (this.parent)._searchMarker
+        if (searchMarker) {
+          for (let i = searchMarker.length - 1; i >= 0; i--) {
+            if (searchMarker[i].nextItem === right) {
+              // @todo do something more efficient than splicing..
+              searchMarker.splice(i, 1)
            }
          }
-        })
+        }
      }
      if (right.keep) {
        this.keep = true
@@ -621,7 +640,7 @@ export class Item extends AbstractStruct {
      this.markDeleted()
      addToDeleteSet(transaction.deleteSet, this.id.client, this.id.clock, this.length)
      addChangedTypeToTransaction(transaction, parent, this.parentSub)
-      this.content.delete(transaction)
+      this.content.delete(transaction, this)
    }
  }

@@ -633,6 +652,7 @@ export class Item extends AbstractStruct {
    if (!this.deleted) {
      throw error.unexpectedCase()
    }
+    this.moved = null
    this.content.gc(store)
    if (parentGCd) {
      replaceStruct(store, this, new GC(this.id, this.length))
@@ -718,7 +738,8 @@ export const contentRefs = [
  readContentType, // 7
  readContentAny, // 8
  readContentDoc, // 9
-  () => { error.unexpectedCase() } // 10 - Skip is not ItemContent
+  () => { error.unexpectedCase() }, // 10 - Skip is not ItemContent
+  readContentMove // 11
 ]

 /**
@@ -785,8 +806,9 @@ export class AbstractContent {

  /**
   * @param {Transaction} transaction
+   * @param {Item} item
   */
-  delete (transaction) {
+  delete (transaction, item) {
    throw error.methodUnimplemented()
  }

--- a/src/types/AbstractType.js
+++ b/src/types/AbstractType.js
@@ -10,7 +10,7 @@ import {
  createID,
  ContentAny,
  ContentBinary,
-  getItemCleanStart,
+  ListIterator,
  ContentDoc, YText, YArray, UpdateEncoderV1, UpdateEncoderV2, Doc, Snapshot, Transaction, EventHandler, YEvent, Item, // eslint-disable-line
 } from '../internals.js'

@@ -21,67 +21,6 @@ import * as math from 'lib0/math'

 const maxSearchMarker = 80

-/**
- * A unique timestamp that identifies each marker.
- *
- * Time is relative,.. this is more like an ever-increasing clock.
- *
- * @type {number}
- */
-let globalSearchMarkerTimestamp = 0
-
-export class ArraySearchMarker {
-  /**
-   * @param {Item} p
-   * @param {number} index
-   */
-  constructor (p, index) {
-    p.marker = true
-    this.p = p
-    this.index = index
-    this.timestamp = globalSearchMarkerTimestamp++
-  }
-}
-
-/**
- * @param {ArraySearchMarker} marker
- */
-const refreshMarkerTimestamp = marker => { marker.timestamp = globalSearchMarkerTimestamp++ }
-
-/**
- * This is rather complex so this function is the only thing that should overwrite a marker
- *
- * @param {ArraySearchMarker} marker
- * @param {Item} p
- * @param {number} index
- */
-const overwriteMarker = (marker, p, index) => {
-  marker.p.marker = false
-  marker.p = p
-  p.marker = true
-  marker.index = index
-  marker.timestamp = globalSearchMarkerTimestamp++
-}
-
-/**
- * @param {Array<ArraySearchMarker>} searchMarker
- * @param {Item} p
- * @param {number} index
- */
-const markPosition = (searchMarker, p, index) => {
-  if (searchMarker.length >= maxSearchMarker) {
-    // override oldest marker (we don't want to create more objects)
-    const marker = searchMarker.reduce((a, b) => a.timestamp < b.timestamp ? a : b)
-    overwriteMarker(marker, p, index)
-    return marker
-  } else {
-    // create new marker
-    const pm = new ArraySearchMarker(p, index)
-    searchMarker.push(pm)
-    return pm
-  }
-}
-
 /**
 * Search marker help us to find positions in the associative array faster.
 *
@@ -89,82 +28,69 @@ const markPosition = (searchMarker, p, index) => {
 *
 * A maximum of `maxSearchMarker` objects are created.
 *
- * This function always returns a refreshed marker (updated timestamp)
- *
+ * @template T
+ * @param {Transaction} tr
 * @param {AbstractType<any>} yarray
 * @param {number} index
+ * @param {function(ListIterator):T} f
 */
-export const findMarker = (yarray, index) => {
-  if (yarray._start === null || index === 0 || yarray._searchMarker === null) {
-    return null
+export const useSearchMarker = (tr, yarray, index, f) => {
+  const searchMarker = yarray._searchMarker
+  if (searchMarker === null || yarray._start === null || index < 5) {
+    return f(new ListIterator(yarray).forward(tr, index))
  }
-  const marker = yarray._searchMarker.length === 0 ? null : yarray._searchMarker.reduce((a, b) => math.abs(index - a.index) < math.abs(index - b.index) ? a : b)
-  let p = yarray._start
-  let pindex = 0
-  if (marker !== null) {
-    p = marker.p
-    pindex = marker.index
-    refreshMarkerTimestamp(marker) // we used it, we might need to use it again
+  if (searchMarker.length === 0) {
+    const sm = new ListIterator(yarray).forward(tr, index)
+    searchMarker.push(sm)
+    if (sm.nextItem) sm.nextItem.marker = true
  }
-  // iterate to right if possible
-  while (p.right !== null && pindex < index) {
-    if (!p.deleted && p.countable) {
-      if (index < pindex + p.length) {
-        break
-      }
-      pindex += p.length
-    }
-    p = p.right
+  const sm = searchMarker.reduce(
+    (a, b, arrayIndex) => math.abs(index - a.index) < math.abs(index - b.index) ? a : b
+  )
+  const newIsCheaper = math.abs(sm.index - index) > index
+  const createFreshMarker = searchMarker.length < maxSearchMarker && (math.abs(sm.index - index) > 5 || newIsCheaper)
+  const fsm = createFreshMarker ? (newIsCheaper ? new ListIterator(yarray) : sm.clone()) : sm
+  const prevItem = /** @type {Item} */ (sm.nextItem)
+  if (createFreshMarker) {
+    searchMarker.push(fsm)
  }
-  // iterate to left if necessary (might be that pindex > index)
-  while (p.left !== null && pindex > index) {
-    p = p.left
-    if (!p.deleted && p.countable) {
-      pindex -= p.length
-    }
-  }
-  // we want to make sure that p can't be merged with left, because that would screw up everything
-  // in that cas just return what we have (it is most likely the best marker anyway)
-  // iterate to left until p can't be merged with left
-  while (p.left !== null && p.left.id.client === p.id.client && p.left.id.clock + p.left.length === p.id.clock) {
-    p = p.left
-    if (!p.deleted && p.countable) {
-      pindex -= p.length
-    }
-  }
-
-  // @todo remove!
-  // assure position
-  // {
-  //   let start = yarray._start
-  //   let pos = 0
-  //   while (start !== p) {
-  //     if (!start.deleted && start.countable) {
-  //       pos += start.length
-  //     }
-  //     start = /** @type {Item} */ (start.right)
-  //   }
-  //   if (pos !== pindex) {
-  //     debugger
-  //     throw new Error('Gotcha position fail!')
-  //   }
-  // }
-  // if (marker) {
-  //   if (window.lengthes == null) {
-  //     window.lengthes = []
-  //     window.getLengthes = () => window.lengthes.sort((a, b) => a - b)
-  //   }
-  //   window.lengthes.push(marker.index - pindex)
-  //   console.log('distance', marker.index - pindex, 'len', p && p.parent.length)
-  // }
-  if (marker !== null && math.abs(marker.index - pindex) < /** @type {YText|YArray<any>} */ (p.parent).length / maxSearchMarker) {
-    // adjust existing marker
-    overwriteMarker(marker, p, pindex)
-    return marker
+  const diff = fsm.index - index
+  if (diff > 0) {
+    fsm.backward(tr, diff)
  } else {
-    // create new marker
-    return markPosition(yarray._searchMarker, p, pindex)
+    fsm.forward(tr, -diff)
  }
+  // @todo remove this tests
+  /*
+  const otherTesting = new ListIterator(yarray)
+  otherTesting.forward(tr, index)
+  if (otherTesting.nextItem !== fsm.nextItem || otherTesting.index !== fsm.index || otherTesting.reachedEnd !== fsm.reachedEnd) {
+    throw new Error('udtirane')
+  }
+  */
+  const result = f(fsm)
+  if (fsm.reachedEnd) {
+    fsm.reachedEnd = false
+    const nextItem = /** @type {Item} */ (fsm.nextItem)
+    if (nextItem.countable && !nextItem.deleted) {
+      fsm.index -= nextItem.length
+    }
+    fsm.rel = 0
+  }
+  if (!createFreshMarker) {
+    // reused old marker and we moved to a different position
+    prevItem.marker = false
+  }
+  const fsmItem = fsm.nextItem
+  if (fsmItem) {
+    if (fsmItem.marker) {
+      // already marked, forget current iterator
+      searchMarker.splice(searchMarker.findIndex(m => m === fsm), 1)
+    } else {
+      fsmItem.marker = true
+    }
+  }
+  return result
 }

 /**
@@ -172,39 +98,25 @@ export const findMarker = (yarray, index) => {
 *
 * This should be called before doing a deletion!
 *
- * @param {Array<ArraySearchMarker>} searchMarker
+ * @param {Array<ListIterator>} searchMarker
 * @param {number} index
 * @param {number} len If insertion, len is positive. If deletion, len is negative.
+ * @param {ListIterator|null} origSearchMarker Do not update this searchmarker because it is the one we used to manipulate. @todo !=null for improved perf in ytext
 */
-export const updateMarkerChanges = (searchMarker, index, len) => {
+export const updateMarkerChanges = (searchMarker, index, len, origSearchMarker) => {
  for (let i = searchMarker.length - 1; i >= 0; i--) {
-    const m = searchMarker[i]
-    if (len > 0) {
-      /**
-       * @type {Item|null}
-       */
-      let p = m.p
-      p.marker = false
-      // Ideally we just want to do a simple position comparison, but this will only work if
-      // search markers don't point to deleted items for formats.
-      // Iterate marker to prev undeleted countable position so we know what to do when updating a position
-      while (p && (p.deleted || !p.countable)) {
-        p = p.left
-        if (p && !p.deleted && p.countable) {
-          // adjust position. the loop should break now
-          m.index -= p.length
-        }
-      }
-      if (p === null || p.marker === true) {
-        // remove search marker if updated position is null or if position is already marked
+    const marker = searchMarker[i]
+    if (marker !== origSearchMarker) {
+      if (len > 0 && index === marker.index) {
+        // inserting at a marked position deletes the marked position because we can't do a simple transformation
+        // (we don't know whether to insert directly before or directly after the position)
        searchMarker.splice(i, 1)
+        if (marker.nextItem) marker.nextItem.marker = false
        continue
      }
-      m.p = p
-      p.marker = true
-    }
-    if (index < m.index || (len > 0 && index === m.index)) { // a simple index <= m.index check would actually suffice
-      m.index = math.max(index, m.index + len)
+      if (index < marker.index) { // a simple index <= m.index check would actually suffice
+        marker.index = math.max(index, marker.index + len)
+      }
    }
  }
 }
@@ -278,13 +190,20 @@ export class AbstractType {
    this._eH = createEventHandler()
    /**
     * Deep event handlers
-     * @type {EventHandler<Array<YEvent<any>>,Transaction>}
+     * @type {EventHandler<Array<YEvent>,Transaction>}
     */
    this._dEH = createEventHandler()
    /**
-     * @type {null | Array<ArraySearchMarker>}
+     * @type {null | Array<ListIterator>}
     */
    this._searchMarker = null
+    /**
+     * You can store custom stuff here.
+     * This might be useful to associate your application state to this shared type.
+     *
+     * @type {Map<any, any>}
+     */
+    this.meta = new Map()
  }

  /**
@@ -364,7 +283,7 @@ export class AbstractType {
  /**
   * Observe all events that are created by this type and its children.
   *
-   * @param {function(Array<YEvent<any>>,Transaction):void} f Observer function
+   * @param {function(Array<YEvent>,Transaction):void} f Observer function
   */
  observeDeep (f) {
    addEventHandlerListener(this._dEH, f)
@@ -382,7 +301,7 @@ export class AbstractType {
  /**
   * Unregister an observer function.
   *
-   * @param {function(Array<YEvent<any>>,Transaction):void} f Observer function
+   * @param {function(Array<YEvent>,Transaction):void} f Observer function
   */
  unobserveDeep (f) {
    removeEventHandlerListener(this._dEH, f)
@@ -594,31 +513,6 @@ export const typeListForEachSnapshot = (type, f, snapshot) => {
  }
 }

-/**
- * @param {AbstractType<any>} type
- * @param {number} index
- * @return {any}
- *
- * @private
- * @function
- */
-export const typeListGet = (type, index) => {
-  const marker = findMarker(type, index)
-  let n = type._start
-  if (marker !== null) {
-    n = marker.p
-    index -= marker.index
-  }
-  for (; n !== null; n = n.right) {
-    if (!n.deleted && n.countable) {
-      if (index < n.length) {
-        return n.content.getContent()[index]
-      }
-      index -= n.length
-    }
-  }
-}
-
 /**
 * @param {Transaction} transaction
 * @param {AbstractType<any>} parent
@@ -683,128 +577,6 @@ export const typeListInsertGenericsAfter = (transaction, parent, referenceItem,
  packJsonContent()
 }

-const lengthExceeded = error.create('Length exceeded!')
-
-/**
- * @param {Transaction} transaction
- * @param {AbstractType<any>} parent
- * @param {number} index
- * @param {Array<Object<string,any>|Array<any>|number|null|string|Uint8Array>} content
- *
- * @private
- * @function
- */
-export const typeListInsertGenerics = (transaction, parent, index, content) => {
-  if (index > parent._length) {
-    throw lengthExceeded
-  }
-  if (index === 0) {
-    if (parent._searchMarker) {
-      updateMarkerChanges(parent._searchMarker, index, content.length)
-    }
-    return typeListInsertGenericsAfter(transaction, parent, null, content)
-  }
-  const startIndex = index
-  const marker = findMarker(parent, index)
-  let n = parent._start
-  if (marker !== null) {
-    n = marker.p
-    index -= marker.index
-    // we need to iterate one to the left so that the algorithm works
-    if (index === 0) {
-      // @todo refactor this as it actually doesn't consider formats
-      n = n.prev // important! get the left undeleted item so that we can actually decrease index
-      index += (n && n.countable && !n.deleted) ? n.length : 0
-    }
-  }
-  for (; n !== null; n = n.right) {
-    if (!n.deleted && n.countable) {
-      if (index <= n.length) {
-        if (index < n.length) {
-          // insert in-between
-          getItemCleanStart(transaction, createID(n.id.client, n.id.clock + index))
-        }
-        break
-      }
-      index -= n.length
-    }
-  }
-  if (parent._searchMarker) {
-    updateMarkerChanges(parent._searchMarker, startIndex, content.length)
-  }
-  return typeListInsertGenericsAfter(transaction, parent, n, content)
-}
-
-/**
- * Pushing content is special as we generally want to push after the last item. So we don't have to update
- * the serach marker.
- *
- * @param {Transaction} transaction
- * @param {AbstractType<any>} parent
- * @param {Array<Object<string,any>|Array<any>|number|null|string|Uint8Array>} content
- *
- * @private
- * @function
- */
-export const typeListPushGenerics = (transaction, parent, content) => {
-  // Use the marker with the highest index and iterate to the right.
-  const marker = (parent._searchMarker || []).reduce((maxMarker, currMarker) => currMarker.index > maxMarker.index ? currMarker : maxMarker, { index: 0, p: parent._start })
-  let n = marker.p
-  if (n) {
-    while (n.right) {
-      n = n.right
-    }
-  }
-  return typeListInsertGenericsAfter(transaction, parent, n, content)
-}
-
-/**
- * @param {Transaction} transaction
- * @param {AbstractType<any>} parent
- * @param {number} index
- * @param {number} length
- *
- * @private
- * @function
- */
-export const typeListDelete = (transaction, parent, index, length) => {
-  if (length === 0) { return }
-  const startIndex = index
-  const startLength = length
-  const marker = findMarker(parent, index)
-  let n = parent._start
-  if (marker !== null) {
-    n = marker.p
-    index -= marker.index
-  }
-  // compute the first item to be deleted
-  for (; n !== null && index > 0; n = n.right) {
-    if (!n.deleted && n.countable) {
-      if (index < n.length) {
-        getItemCleanStart(transaction, createID(n.id.client, n.id.clock + index))
-      }
-      index -= n.length
-    }
-  }
-  // delete all items until done
-  while (length > 0 && n !== null) {
-    if (!n.deleted) {
-      if (length < n.length) {
-        getItemCleanStart(transaction, createID(n.id.client, n.id.clock + length))
-      }
-      n.delete(transaction)
-      length -= n.length
-    }
-    n = n.right
-  }
-  if (length > 0) {
-    throw lengthExceeded
-  }
-  if (parent._searchMarker) {
-    updateMarkerChanges(parent._searchMarker, startIndex, -startLength + length /* in case we remove the above exception */)
-  }
-}
-
 /**
 * @param {Transaction} transaction
 * @param {AbstractType<any>} parent
--- a/src/types/YArray.js
+++ b/src/types/YArray.js
@@ -5,25 +5,18 @@
 import {
  YEvent,
  AbstractType,
-  typeListGet,
-  typeListToArray,
-  typeListForEach,
-  typeListCreateIterator,
-  typeListInsertGenerics,
-  typeListPushGenerics,
-  typeListDelete,
-  typeListMap,
  YArrayRefID,
  callTypeObservers,
  transact,
-  ArraySearchMarker, UpdateDecoderV1, UpdateDecoderV2, UpdateEncoderV1, UpdateEncoderV2, Doc, Transaction, Item // eslint-disable-line
+  ListIterator,
+  useSearchMarker,
+  createRelativePositionFromTypeIndex,
+  UpdateDecoderV1, UpdateDecoderV2, UpdateEncoderV1, UpdateEncoderV2, Doc, Transaction, Item // eslint-disable-line
 } from '../internals.js'
-import { typeListSlice } from './AbstractType.js'

 /**
 * Event that describes the changes on a YArray
 * @template T
- * @extends YEvent<YArray<T>>
 */
 export class YArrayEvent extends YEvent {
  /**
@@ -51,7 +44,7 @@ export class YArray extends AbstractType {
     */
    this._prelimContent = []
    /**
-     * @type {Array<ArraySearchMarker>}
+     * @type {Array<ListIterator>}
     */
    this._searchMarker = []
  }
@@ -131,12 +124,70 @@ export class YArray extends AbstractType {
   * @param {Array<T>} content The array of content
   */
  insert (index, content) {
+    if (content.length > 0) {
+      if (this.doc !== null) {
+        transact(this.doc, transaction => {
+          useSearchMarker(transaction, this, index, walker =>
+            walker.insertArrayValue(transaction, content)
+          )
+        })
+      } else {
+        /** @type {Array<any>} */ (this._prelimContent).splice(index, 0, ...content)
+      }
+    }
+  }
+
+  /**
+   * Move a single item from $index to $target.
+   *
+   * @todo make sure that collapsed moves are removed (i.e. when moving the same item twice)
+   *
+   * @param {number} index
+   * @param {number} target
+   */
+  move (index, target) {
+    if (index === target || index + 1 === target || index >= this.length) {
+      // It doesn't make sense to move a range into the same range (it's basically a no-op).
+      return
+    }
    if (this.doc !== null) {
      transact(this.doc, transaction => {
-        typeListInsertGenerics(transaction, this, index, content)
+        const left = createRelativePositionFromTypeIndex(this, index, 1)
+        const right = left.clone()
+        right.assoc = -1
+        useSearchMarker(transaction, this, target, walker => {
+          walker.insertMove(transaction, left, right)
+        })
      })
    } else {
-      /** @type {Array<any>} */ (this._prelimContent).splice(index, 0, ...content)
+      const content = /** @type {Array<any>} */ (this._prelimContent).splice(index, 1)
+      ;/** @type {Array<any>} */ (this._prelimContent).splice(target, 0, ...content)
+    }
+  }
+
+  /**
+   * @param {number} start Inclusive move-start
+   * @param {number} end Inclusive move-end
+   * @param {number} target
+   * @param {number} assocStart >=0 if start should be associated with the right character. See relative-position assoc parameter.
+   * @param {number} assocEnd >= 0 if end should be associated with the right character.
+   */
+  moveRange (start, end, target, assocStart = 1, assocEnd = -1) {
+    if (start <= target && target <= end) {
+      // It doesn't make sense to move a range into the same range (it's basically a no-op).
+      return
+    }
+    if (this.doc !== null) {
+      transact(this.doc, transaction => {
+        const left = createRelativePositionFromTypeIndex(this, start, assocStart)
+        const right = createRelativePositionFromTypeIndex(this, end + 1, assocEnd)
+        useSearchMarker(transaction, this, target, walker => {
+          walker.insertMove(transaction, left, right)
+        })
+      })
+    } else {
+      const content = /** @type {Array<any>} */ (this._prelimContent).splice(start, end - start + 1)
+      ;/** @type {Array<any>} */ (this._prelimContent).splice(target, 0, ...content)
    }
  }

@@ -144,17 +195,9 @@ export class YArray extends AbstractType {
   * Appends content to this YArray.
   *
   * @param {Array<T>} content Array of content to append.
-   *
-   * @todo Use the following implementation in all types.
   */
  push (content) {
-    if (this.doc !== null) {
-      transact(this.doc, transaction => {
-        typeListPushGenerics(transaction, this, content)
-      })
-    } else {
-      /** @type {Array<any>} */ (this._prelimContent).push(...content)
-    }
+    this.insert(this.length, content)
  }

  /**
@@ -175,7 +218,9 @@ export class YArray extends AbstractType {
  delete (index, length = 1) {
    if (this.doc !== null) {
      transact(this.doc, transaction => {
-        typeListDelete(transaction, this, index, length)
+        useSearchMarker(transaction, this, index, walker =>
+          walker.delete(transaction, length)
+        )
      })
    } else {
      /** @type {Array<any>} */ (this._prelimContent).splice(index, length)
@@ -189,7 +234,11 @@ export class YArray extends AbstractType {
   * @return {T}
   */
  get (index) {
-    return typeListGet(this, index)
+    return transact(/** @type {Doc} */ (this.doc), transaction =>
+      useSearchMarker(transaction, this, index, walker =>
+        walker.slice(transaction, 1)[0]
+      )
+    )
  }

  /**
@@ -198,7 +247,9 @@ export class YArray extends AbstractType {
   * @return {Array<T>}
   */
  toArray () {
-    return typeListToArray(this)
+    return transact(/** @type {Doc} */ (this.doc), tr =>
+      new ListIterator(this).slice(tr, this.length)
+    )
  }

  /**
@@ -209,7 +260,11 @@ export class YArray extends AbstractType {
   * @return {Array<T>}
   */
  slice (start = 0, end = this.length) {
-    return typeListSlice(this, start, end)
+    return transact(/** @type {Doc} */ (this.doc), transaction =>
+      useSearchMarker(transaction, this, start, walker =>
+        walker.slice(transaction, end < 0 ? this.length + end - start : end - start)
+      )
+    )
  }

  /**
@@ -231,7 +286,9 @@ export class YArray extends AbstractType {
   *                 callback function
   */
  map (f) {
-    return typeListMap(this, /** @type {any} */ (f))
+    return transact(/** @type {Doc} */ (this.doc), tr =>
+      new ListIterator(this).map(tr, f)
+    )
  }

  /**
@@ -240,14 +297,16 @@ export class YArray extends AbstractType {
   * @param {function(T,number,YArray<T>):void} f A function to execute on every element of this YArray.
   */
  forEach (f) {
-    typeListForEach(this, f)
+    return transact(/** @type {Doc} */ (this.doc), tr =>
+      new ListIterator(this).forEach(tr, f)
+    )
  }

  /**
   * @return {IterableIterator<T>}
   */
  [Symbol.iterator] () {
-    return typeListCreateIterator(this)
+    return this.toArray().values()
  }

  /**
--- a/src/types/YMap.js
+++ b/src/types/YMap.js
@@ -21,7 +21,6 @@ import * as iterator from 'lib0/iterator'

 /**
 * @template T
- * @extends YEvent<YMap<T>>
 * Event that describes the changes on a YMap.
 */
 export class YMapEvent extends YEvent {
--- a/src/types/YText.js
+++ b/src/types/YText.js
@@ -20,14 +20,15 @@ import {
  splitSnapshotAffectedStructs,
  iterateDeletedStructs,
  iterateStructs,
-  findMarker,
  typeMapDelete,
  typeMapSet,
  typeMapGet,
  typeMapGetAll,
  updateMarkerChanges,
  ContentType,
-  ArraySearchMarker, UpdateDecoderV1, UpdateDecoderV2, UpdateEncoderV1, UpdateEncoderV2, ID, Doc, Item, Snapshot, Transaction // eslint-disable-line
+  useSearchMarker,
+  findIndexCleanStart,
+  ListIterator, UpdateDecoderV1, UpdateDecoderV2, UpdateEncoderV1, UpdateEncoderV2, ID, Doc, Item, Snapshot, Transaction // eslint-disable-line
 } from '../internals.js'

 import * as object from 'lib0/object'
@@ -125,10 +126,30 @@ const findNextPosition = (transaction, pos, count) => {
 */
 const findPosition = (transaction, parent, index) => {
  const currentAttributes = new Map()
-  const marker = findMarker(parent, index)
-  if (marker) {
-    const pos = new ItemTextListPosition(marker.p.left, marker.p, marker.index, currentAttributes)
-    return findNextPosition(transaction, pos, index - marker.index)
+  if (parent._searchMarker) {
+    return useSearchMarker(transaction, parent, index, listIter => {
+      let left, right
+      if (listIter.rel > 0) {
+        // must exist because rel > 0
+        const nextItem = /** @type {Item} */ (listIter.nextItem)
+        if (listIter.rel === nextItem.length) {
+          left = nextItem
+          right = left.right
+        } else {
+          const structs = /** @type {Array<Item|GC>} */ (transaction.doc.store.clients.get(nextItem.id.client))
+          const after = /** @type {Item} */ (structs[findIndexCleanStart(transaction, structs, nextItem.id.clock + listIter.rel)])
+          listIter.nextItem = after
+          listIter.rel = 0
+          left = listIter.left
+          right = listIter.right
+        }
+      } else {
+        left = listIter.left
+        right = listIter.right
+      }
+      // @todo this should simply split if .rel > 0
+      return new ItemTextListPosition(left, right, index, currentAttributes)
+    })
  } else {
    const pos = new ItemTextListPosition(null, parent._start, 0, currentAttributes)
    return findNextPosition(transaction, pos, index)
@@ -264,7 +285,7 @@ const insertText = (transaction, parent, currPos, text, attributes) => {
  const content = text.constructor === String ? new ContentString(/** @type {string} */ (text)) : (text instanceof AbstractType ? new ContentType(text) : new ContentEmbed(text))
  let { left, right, index } = currPos
  if (parent._searchMarker) {
-    updateMarkerChanges(parent._searchMarker, currPos.index, content.getLength())
+    updateMarkerChanges(parent._searchMarker, currPos.index, content.getLength(), null)
  }
  right = new Item(createID(ownClientId, getState(doc.store, ownClientId)), left, left && left.lastId, right, right && right.id, parent, null, content)
  right.integrate(transaction, 0)
@@ -291,8 +312,7 @@ const formatText = (transaction, parent, currPos, length, attributes) => {
  const negatedAttributes = insertAttributes(transaction, parent, currPos, attributes)
  // iterate until first non-format or null is found
  // delete all formats with attributes[format.key] != null
-  // also check the attributes after the first non-format as we do not want to insert redundant negated attributes there
-  while (currPos.right !== null && (length > 0 || currPos.right.content.constructor === ContentFormat)) {
+  while (length > 0 && currPos.right !== null) {
    if (!currPos.right.deleted) {
      switch (currPos.right.content.constructor) {
        case ContentFormat: {
@@ -339,16 +359,14 @@ const formatText = (transaction, parent, currPos, length, attributes) => {
 *
 * @param {Transaction} transaction
 * @param {Item} start
- * @param {Item|null} curr exclusive end, automatically iterates to the next Content Item
+ * @param {Item|null} end exclusive end, automatically iterates to the next Content Item
 * @param {Map<string,any>} startAttributes
- * @param {Map<string,any>} currAttributes
+ * @param {Map<string,any>} endAttributes This attribute is modified!
 * @return {number} The amount of formatting Items deleted.
 *
 * @function
 */
-const cleanupFormattingGap = (transaction, start, curr, startAttributes, currAttributes) => {
-  let end = curr
-  const endAttributes = map.copy(currAttributes)
+const cleanupFormattingGap = (transaction, start, end, startAttributes, endAttributes) => {
  while (end && (!end.countable || end.deleted)) {
    if (!end.deleted && end.content.constructor === ContentFormat) {
      updateCurrentAttributes(endAttributes, /** @type {ContentFormat} */ (end.content))
@@ -356,11 +374,7 @@ const cleanupFormattingGap = (transaction, start, curr, startAttributes, currAtt
    end = end.right
  }
  let cleanups = 0
-  let reachedEndOfCurr = false
  while (start !== end) {
-    if (curr === start) {
-      reachedEndOfCurr = true
-    }
    if (!start.deleted) {
      const content = start.content
      switch (content.constructor) {
@@ -370,9 +384,6 @@ const cleanupFormattingGap = (transaction, start, curr, startAttributes, currAtt
            // Either this format is overwritten or it is not necessary because the attribute already existed.
            start.delete(transaction)
            cleanups++
-            if (!reachedEndOfCurr && (currAttributes.get(key) || null) === value && (startAttributes.get(key) || null) !== value) {
-              currAttributes.delete(key)
-            }
          }
          break
        }
@@ -475,11 +486,11 @@ const deleteText = (transaction, currPos, length) => {
    currPos.forward()
  }
  if (start) {
-    cleanupFormattingGap(transaction, start, currPos.right, startAttrs, currPos.currentAttributes)
+    cleanupFormattingGap(transaction, start, currPos.right, startAttrs, map.copy(currPos.currentAttributes))
  }
  const parent = /** @type {AbstractType<any>} */ (/** @type {Item} */ (currPos.left || currPos.right).parent)
  if (parent._searchMarker) {
-    updateMarkerChanges(parent._searchMarker, currPos.index, -startLength + length)
+    updateMarkerChanges(parent._searchMarker, currPos.index, -startLength + length, null)
  }
  return currPos
 }
@@ -512,7 +523,6 @@ const deleteText = (transaction, currPos, length) => {
  */

 /**
- * @extends YEvent<YText>
 * Event that describes the changes on a YText type.
 */
 export class YTextEvent extends YEvent {
@@ -695,7 +705,7 @@ export class YTextEvent extends YEvent {
                    } else {
                      attributes[key] = value
                    }
-                  } else if (value !== null) {
+                  } else {
                    item.delete(transaction)
                  }
                }
@@ -721,7 +731,7 @@ export class YTextEvent extends YEvent {
                    } else {
                      attributes[key] = value
                    }
-                  } else if (attr !== null) { // this will be cleaned up automatically by the contextless cleanup function
+                  } else {
                    item.delete(transaction)
                  }
                }
@@ -775,7 +785,7 @@ export class YText extends AbstractType {
     */
    this._pending = string !== undefined ? [() => this.insert(0, string)] : []
    /**
-     * @type {Array<ArraySearchMarker>}
+     * @type {Array<ListIterator>}
     */
    this._searchMarker = []
  }
--- a/src/types/YXmlEvent.js
+++ b/src/types/YXmlEvent.js
@@ -5,7 +5,6 @@ import {
 } from '../internals.js'

 /**
- * @extends YEvent<YXmlElement|YXmlText|YXmlFragment>
 * An Event that describes changes on a YXml Element or Yxml Fragment
 */
 export class YXmlEvent extends YEvent {
--- a/src/types/YXmlFragment.js
+++ b/src/types/YXmlFragment.js
@@ -8,15 +8,13 @@ import {
  AbstractType,
  typeListMap,
  typeListForEach,
-  typeListInsertGenerics,
  typeListInsertGenericsAfter,
-  typeListDelete,
  typeListToArray,
  YXmlFragmentRefID,
  callTypeObservers,
  transact,
-  typeListGet,
  typeListSlice,
+  useSearchMarker,
  UpdateDecoderV1, UpdateDecoderV2, UpdateEncoderV1, UpdateEncoderV2, Doc, ContentType, Transaction, Item, YXmlText, YXmlHook, Snapshot // eslint-disable-line
 } from '../internals.js'

@@ -304,9 +302,11 @@ export class YXmlFragment extends AbstractType {
   */
  insert (index, content) {
    if (this.doc !== null) {
-      transact(this.doc, transaction => {
-        typeListInsertGenerics(transaction, this, index, content)
-      })
+      return transact(/** @type {Doc} */ (this.doc), transaction =>
+        useSearchMarker(transaction, this, index, walker =>
+          walker.insertArrayValue(transaction, content)
+        )
+      )
    } else {
      // @ts-ignore _prelimContent is defined because this is not yet integrated
      this._prelimContent.splice(index, 0, ...content)
@@ -347,9 +347,11 @@ export class YXmlFragment extends AbstractType {
   */
  delete (index, length = 1) {
    if (this.doc !== null) {
-      transact(this.doc, transaction => {
-        typeListDelete(transaction, this, index, length)
-      })
+      transact(/** @type {Doc} */ (this.doc), transaction =>
+        useSearchMarker(transaction, this, index, walker =>
+          walker.delete(transaction, length)
+        )
+      )
    } else {
      // @ts-ignore _prelimContent is defined because this is not yet integrated
      this._prelimContent.splice(index, length)
@@ -390,7 +392,11 @@ export class YXmlFragment extends AbstractType {
   * @return {YXmlElement|YXmlText}
   */
  get (index) {
-    return typeListGet(this, index)
+    return transact(/** @type {Doc} */ (this.doc), transaction =>
+      useSearchMarker(transaction, this, index, walker =>
+        walker.slice(transaction, 1)[0]
+      )
+    )
  }

  /**
--- a/src/utils/Doc.js
+++ b/src/utils/Doc.js
@@ -48,7 +48,7 @@ export class Doc extends Observable {
    this.guid = guid
    this.collectionid = collectionid
    /**
-     * @type {Map<string, AbstractType<YEvent<any>>>}
+     * @type {Map<string, AbstractType<YEvent>>}
     */
    this.share = new Map()
    this.store = new StructStore()
--- a/src/utils/ListIterator.js
+++ b/src/utils/ListIterator.js
@@ -0,0 +1,510 @@
+import * as error from 'lib0/error'
+
+import {
+  getItemCleanStart,
+  createID,
+  getMovedCoords,
+  updateMarkerChanges,
+  getState,
+  ContentAny,
+  ContentBinary,
+  ContentType,
+  ContentDoc,
+  Doc,
+  RelativePosition, ID, AbstractContent, ContentMove, Transaction, Item, AbstractType // eslint-disable-line
+} from '../internals.js'
+
+const lengthExceeded = error.create('Length exceeded!')
+
+/**
+ * @todo rename to walker?
+ * @todo check that inserting character one after another always reuses ListIterators
+ */
+export class ListIterator {
+  /**
+   * @param {AbstractType<any>} type
+   */
+  constructor (type) {
+    this.type = type
+    /**
+     * Current index-position
+     */
+    this.index = 0
+    /**
+     * Relative position to the current item (if item.content.length > 1)
+     */
+    this.rel = 0
+    /**
+     * This refers to the current right item, unless reachedEnd is true. Then it refers to the left item.
+     *
+     * @public
+     * @type {Item | null}
+     */
+    this.nextItem = type._start
+    this.reachedEnd = type._start === null
+    /**
+     * @type {Item | null}
+     */
+    this.currMove = null
+    /**
+     * @type {Item | null}
+     */
+    this.currMoveStart = null
+    /**
+     * @type {Item | null}
+     */
+    this.currMoveEnd = null
+    /**
+     * @type {Array<{ start: Item | null, end: Item | null, move: Item }>}
+     */
+    this.movedStack = []
+  }
+
+  clone () {
+    const iter = new ListIterator(this.type)
+    iter.index = this.index
+    iter.rel = this.rel
+    iter.nextItem = this.nextItem
+    iter.reachedEnd = this.reachedEnd
+    iter.currMove = this.currMove
+    iter.currMoveStart = this.currMoveStart
+    iter.currMoveEnd = this.currMoveEnd
+    iter.movedStack = this.movedStack.slice()
+    return iter
+  }
+
+  /**
+   * @type {Item | null}
+   */
+  get left () {
+    if (this.reachedEnd) {
+      return this.nextItem
+    } else {
+      return this.nextItem && this.nextItem.left
+    }
+  }
+
+  /**
+   * @type {Item | null}
+   */
+  get right () {
+    if (this.reachedEnd) {
+      return null
+    } else {
+      return this.nextItem
+    }
+  }
+
+  /**
+   * @param {Transaction} tr
+   * @param {number} index
+   */
+  moveTo (tr, index) {
+    const diff = index - this.index
+    if (diff > 0) {
+      this.forward(tr, diff)
+    } else if (diff < 0) {
+      this.backward(tr, -diff)
+    }
+  }
+
+  /**
+   * @param {Transaction} tr
+   * @param {number} len
+   */
+  forward (tr, len) {
+    if (this.index + len > this.type._length) {
+      throw lengthExceeded
+    }
+    let item = this.nextItem
+    this.index += len
+    if (this.rel) {
+      len += this.rel
+      this.rel = 0
+    }
+    while ((!this.reachedEnd || this.currMove !== null) && (len > 0 || (len === 0 && item && (!item.countable || item.deleted || item === this.currMoveEnd || (this.reachedEnd && this.currMoveEnd === null) || item.moved !== this.currMove)))) {
+      if (item === this.currMoveEnd || (this.currMoveEnd === null && this.reachedEnd && this.currMove)) {
+        item = /** @type {Item} */ (this.currMove) // we iterate to the right after the current condition
+        const { start, end, move } = this.movedStack.pop() || { start: null, end: null, move: null }
+        this.currMove = move
+        this.currMoveStart = start
+        this.currMoveEnd = end
+        this.reachedEnd = false
+      } else if (item === null) {
+        break
+      } else if (item.countable && !item.deleted && item.moved === this.currMove && len > 0) {
+        len -= item.length
+        if (len < 0) {
+          this.rel = item.length + len
+          len = 0
+          break
+        }
+      } else if (item.content.constructor === ContentMove && item.moved === this.currMove) {
+        if (this.currMove) {
+          this.movedStack.push({ start: this.currMoveStart, end: this.currMoveEnd, move: this.currMove })
+        }
+        const { start, end } = getMovedCoords(item.content, tr)
+        this.currMove = item
+        this.currMoveStart = start
+        this.currMoveEnd = end
+        item = start
+        continue
+      }
+      if (item.right) {
+        item = item.right
+      } else {
+        this.reachedEnd = true
+      }
+    }
+    this.index -= len
+    this.nextItem = item
+    return this
+  }
+
+  /**
+   * @param {Transaction} tr
+   */
+  reduceMoves (tr) {
+    let item = this.nextItem
+    if (item !== null) {
+      while (item === this.currMoveStart) {
+        item = /** @type {Item} */ (this.currMove) // we iterate to the left after the current condition
+        const { start, end, move } = this.movedStack.pop() || { start: null, end: null, move: null }
+        this.currMove = move
+        this.currMoveStart = start
+        this.currMoveEnd = end
+      }
+      this.nextItem = item
+    }
+  }
+
+  /**
+   * @param {Transaction} tr
+   * @param {number} len
+   * @return {ListIterator}
+   */
+  backward (tr, len) {
+    if (this.index - len < 0) {
+      throw lengthExceeded
+    }
+    this.index -= len
+    if (this.reachedEnd) {
+      const nextItem = /** @type {Item} */ (this.nextItem)
+      this.rel = nextItem.countable && !nextItem.deleted ? nextItem.length : 0
+      this.reachedEnd = false
+    }
+    if (this.rel >= len) {
+      this.rel -= len
+      return this
+    }
+    let item = this.nextItem && this.nextItem.left
+    if (this.rel) {
+      len -= this.rel
+      this.rel = 0
+    }
+    while (item && len > 0) {
+      if (item.countable && !item.deleted && item.moved === this.currMove) {
+        len -= item.length
+        if (len < 0) {
+          this.rel = -len
+          len = 0
+        }
+        if (len === 0) {
+          break
+        }
+      } else if (item.content.constructor === ContentMove && item.moved === this.currMove) {
+        if (this.currMove) {
+          this.movedStack.push({ start: this.currMoveStart, end: this.currMoveEnd, move: this.currMove })
+        }
+        const { start, end } = getMovedCoords(item.content, tr)
+        this.currMove = item
+        this.currMoveStart = start
+        this.currMoveEnd = end
+        item = start
+        continue
+      }
+      if (item === this.currMoveStart) {
+        item = /** @type {Item} */ (this.currMove) // we iterate to the left after the current condition
+        const { start, end, move } = this.movedStack.pop() || { start: null, end: null, move: null }
+        this.currMove = move
+        this.currMoveStart = start
+        this.currMoveEnd = end
+      }
+      item = item.left
+    }
+    this.nextItem = item
+    return this
+  }
+
+  /**
+   * @template {{length: number}} T
+   * @param {Transaction} tr
+   * @param {number} len
+   * @param {T} value the initial content
+   * @param {function(AbstractContent, number, number):T} slice
+   * @param {function(T, T): T} concat
+   */
+  _slice (tr, len, value, slice, concat) {
+    this.index += len
+    while (len > 0 && !this.reachedEnd) {
+      while (this.nextItem && this.nextItem.countable && !this.reachedEnd && len > 0 && this.nextItem !== this.currMoveEnd) {
+        if (!this.nextItem.deleted && this.nextItem.moved === this.currMove) {
+          const item = this.nextItem
+          const slicedContent = slice(item.content, this.rel, len)
+          len -= slicedContent.length
+          value = concat(value, slicedContent)
+          if (item.length !== slicedContent.length) {
+            if (this.rel + slicedContent.length === item.length) {
+              this.rel = 0
+            } else {
+              this.rel += slicedContent.length
+              continue // do not iterate to item.right
+            }
+          }
+        }
+        if (this.nextItem.right) {
+          this.nextItem = this.nextItem.right
+        } else {
+          this.reachedEnd = true
+        }
+      }
+      if (this.nextItem && (!this.reachedEnd || this.currMove !== null) && len > 0) {
+        this.forward(tr, 0)
+      }
+    }
+    if (len < 0) {
+      this.index -= len
+    }
+    return value
+  }
+
+  /**
+   * @param {Transaction} tr
+   * @param {number} len
+   */
+  delete (tr, len) {
+    const startLength = len
+    const sm = this.type._searchMarker
+    let item = this.nextItem
+    while (len > 0) {
+      while (item && !item.deleted && item.countable && !this.reachedEnd && len > 0 && item.moved === this.currMove && item !== this.currMoveEnd) {
+        if (this.rel > 0) {
+          item = getItemCleanStart(tr, createID(item.id.client, item.id.clock + this.rel))
+          this.rel = 0
+        }
+        if (len < item.length) {
+          getItemCleanStart(tr, createID(item.id.client, item.id.clock + len))
+        }
+        len -= item.length
+        item.delete(tr)
+        if (item.right) {
+          item = item.right
+        } else {
+          this.reachedEnd = true
+        }
+      }
+      if (len > 0) {
+        this.nextItem = item
+        this.forward(tr, 0)
+        item = this.nextItem
+      }
+    }
+    this.nextItem = item
+    if (sm) {
+      updateMarkerChanges(sm, this.index, -startLength + len, this)
+    }
+  }
+
+  /**
+   * @param {Transaction} tr
+   */
+  _splitRel (tr) {
+    if (this.rel > 0) {
+      /**
+       * @type {ID}
+       */
+      const itemid = /** @type {Item} */ (this.nextItem).id
+      this.nextItem = getItemCleanStart(tr, createID(itemid.client, itemid.clock + this.rel))
+      this.rel = 0
+    }
+  }
+
+  /**
+   * Important: you must update markers after calling this method!
+   *
+   * @param {Transaction} tr
+   * @param {Array<AbstractContent>} content
+   */
+  insertContents (tr, content) {
+    this.reduceMoves(tr)
+    this._splitRel(tr)
+    const parent = this.type
+    const store = tr.doc.store
+    const ownClientId = tr.doc.clientID
+    /**
+     * @type {Item | null}
+     */
+    const right = this.right
+
+    /**
+     * @type {Item | null}
+     */
+    let left = this.left
+    content.forEach(c => {
+      left = new Item(createID(ownClientId, getState(store, ownClientId)), left, left && left.lastId, right, right && right.id, parent, null, c)
+      left.integrate(tr, 0)
+    })
+    if (right === null) {
+      this.nextItem = left
+      this.reachedEnd = true
+    } else {
+      this.nextItem = right
+    }
+  }
+
+  /**
+   * @param {Transaction} tr
+   * @param {RelativePosition} start
+   * @param {RelativePosition} end
+   */
+  insertMove (tr, start, end) {
+    this.insertContents(tr, [new ContentMove(start, end, -1)]) // @todo adjust priority
+    // @todo is there a better alrogirthm to update searchmarkers? We could simply remove the markers that are in the updated range.
+    // Also note that searchmarkers are updated in insertContents as well.
+    const sm = this.type._searchMarker
+    if (sm) sm.length = 0
+  }
+
+  /**
+   * @param {Transaction} tr
+   * @param {Array<Object<string,any>|Array<any>|boolean|number|null|string|Uint8Array>} values
+   */
+  insertArrayValue (tr, values) {
+    this._splitRel(tr)
+    const sm = this.type._searchMarker
+    /**
+     * @type {Array<AbstractContent>}
+     */
+    const contents = []
+    /**
+     * @type {Array<Object|Array<any>|number|null>}
+     */
+    let jsonContent = []
+    const packJsonContent = () => {
+      if (jsonContent.length > 0) {
+        contents.push(new ContentAny(jsonContent))
+        jsonContent = []
+      }
+    }
+    values.forEach(c => {
+      if (c === null) {
+        jsonContent.push(c)
+      } else {
+        switch (c.constructor) {
+          case Number:
+          case Object:
+          case Boolean:
+          case Array:
+          case String:
+            jsonContent.push(c)
+            break
+          default:
+            packJsonContent()
+            switch (c.constructor) {
+              case Uint8Array:
+              case ArrayBuffer:
+                contents.push(new ContentBinary(new Uint8Array(/** @type {Uint8Array} */ (c))))
+                break
+              case Doc:
+                contents.push(new ContentDoc(/** @type {Doc} */ (c)))
+                break
+              default:
+                if (c instanceof AbstractType) {
+                  contents.push(new ContentType(c))
+                } else {
+                  throw new Error('Unexpected content type in insert operation')
+                }
+            }
+        }
+      }
+    })
+    packJsonContent()
+    this.insertContents(tr, contents)
+    this.index += values.length
+    if (sm) {
+      updateMarkerChanges(sm, this.index - values.length, values.length, this)
+    }
+  }
+
+  /**
+   * @param {Transaction} tr
+   * @param {number} len
+   */
+  slice (tr, len) {
+    return this._slice(tr, len, [], sliceArrayContent, concatArrayContent)
+  }
+
+  /**
+   * @param {Transaction} tr
+   * @param {function(any, number, any):void} f
+   */
+  forEach (tr, f) {
+    for (const val of this.values(tr)) {
+      f(val, this.index, this.type)
+    }
+  }
+
+  /**
+   * @template T
+   * @param {Transaction} tr
+   * @param {function(any, number, any):T} f
+   * @return {Array<T>}
+   */
+  map (tr, f) {
+    const arr = new Array(this.type._length - this.index)
+    let i = 0
+    for (const val of this.values(tr)) {
+      arr[i++] = f(val, this.index, this.type)
+    }
+    return arr
+  }
+
+  /**
+   * @param {Transaction} tr
+   */
+  values (tr) {
+    return {
+      [Symbol.iterator] () {
+        return this
+      },
+      next: () => {
+        if (this.reachedEnd || this.index === this.type._length) {
+          return { done: true }
+        }
+        const [value] = this.slice(tr, 1)
+        return {
+          done: false,
+          value: value
+        }
+      }
+    }
+  }
+}
+
+/**
+ * @param {AbstractContent} itemcontent
+ * @param {number} start
+ * @param {number} len
+ */
+const sliceArrayContent = (itemcontent, start, len) => {
+  const content = itemcontent.getContent()
+  return content.length <= len && start === 0 ? content : content.slice(start, start + len)
+}
+/**
+ * @param {Array<any>} content
+ * @param {Array<any>} added
+ */
+const concatArrayContent = (content, added) => {
+  content.push(...added)
+  return content
+}
--- a/src/utils/RelativePosition.js
+++ b/src/utils/RelativePosition.js
@@ -9,6 +9,8 @@ import {
  createID,
  ContentType,
  followRedone,
+  transact,
+  useSearchMarker,
  ID, Doc, AbstractType // eslint-disable-line
 } from '../internals.js'

@@ -73,6 +75,10 @@ export class RelativePosition {
     */
    this.assoc = assoc
  }
+
+  clone () {
+    return new RelativePosition(this.type, this.tname, this.item, this.assoc)
+  }
 }

 /**
@@ -161,7 +167,6 @@ export const createRelativePosition = (type, item, assoc) => {
 * @function
 */
 export const createRelativePositionFromTypeIndex = (type, index, assoc = 0) => {
-  let t = type._start
  if (assoc < 0) {
    // associated to the left character or the beginning of a type, increment index if possible.
    if (index === 0) {
@@ -169,21 +174,17 @@ export const createRelativePositionFromTypeIndex = (type, index, assoc = 0) => {
    }
    index--
  }
-  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), assoc)
+  return transact(/** @type {Doc} */ (type.doc), tr =>
+    useSearchMarker(tr, type, index, walker => {
+      if (walker.reachedEnd) {
+        const item = assoc < 0 ? /** @type {Item} */ (walker.nextItem).lastId : null
+        return createRelativePosition(type, item, assoc)
+      } else {
+        const id = /** @type {Item} */ (walker.nextItem).id
+        return createRelativePosition(type, createID(id.client, id.clock + walker.rel), assoc)
      }
-      index -= t.length
-    }
-    if (t.right === null && assoc < 0) {
-      // left-associated position, return last available id
-      return createRelativePosition(type, t.lastId, assoc)
-    }
-    t = t.right
-  }
-  return createRelativePosition(type, null, assoc)
+    })
+  )
 }

 /**
--- a/src/utils/StructStore.js
+++ b/src/utils/StructStore.js
@@ -199,19 +199,18 @@ export const getItemCleanStart = (transaction, id) => {
 * 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 {Item}
 *
 * @private
 * @function
 */
-export const getItemCleanEnd = (transaction, store, id) => {
+export const getItemCleanEnd = (transaction, id) => {
  /**
   * @type {Array<Item>}
   */
  // @ts-ignore
-  const structs = store.clients.get(id.client)
+  const structs = transaction.doc.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) {
--- a/src/utils/Transaction.js
+++ b/src/utils/Transaction.js
@@ -75,13 +75,13 @@ export class Transaction {
     * All types that were directly modified (property added or child
     * inserted/deleted). New types are not included in this Set.
     * Maps from type to parentSubs (`item.parentSub = null` for YArray)
-     * @type {Map<AbstractType<YEvent<any>>,Set<String|null>>}
+     * @type {Map<AbstractType<YEvent>,Set<String|null>>}
     */
    this.changed = new Map()
    /**
     * Stores the events for the types that observe also child elements.
     * It is mainly used by `observeDeep`.
-     * @type {Map<AbstractType<YEvent<any>>,Array<YEvent<any>>>}
+     * @type {Map<AbstractType<YEvent>,Array<YEvent>>}
     */
    this.changedParentTypes = new Map()
    /**
@@ -114,6 +114,14 @@ export class Transaction {
     * @type {Set<Doc>}
     */
    this.subdocsLoaded = new Set()
+    /**
+     * We store the reference that last moved an item.
+     * This is needed to compute the delta when multiple ContentMove move
+     * the same item.
+     *
+     * @type {Map<Item, Item>}
+     */
+    this.prevMoved = new Map()
  }
 }

@@ -148,7 +156,7 @@ export const nextID = transaction => {
 * did not change, it was just added and we should not fire events for `type`.
 *
 * @param {Transaction} transaction
- * @param {AbstractType<YEvent<any>>} type
+ * @param {AbstractType<YEvent>} type
 * @param {string|null} parentSub
 */
 export const addChangedTypeToTransaction = (transaction, type, parentSub) => {
@@ -377,9 +385,12 @@ const cleanupTransactions = (transactionCleanups, i) => {
 /**
 * Implements the functionality of `y.transact(()=>{..})`
 *
+ * @template T
+ *
 * @param {Doc} doc
- * @param {function(Transaction):void} f
+ * @param {function(Transaction):T} f
 * @param {any} [origin=true]
+ * @return {T}
 *
 * @function
 */
@@ -395,8 +406,9 @@ export const transact = (doc, f, origin = null, local = true) => {
    }
    doc.emit('beforeTransaction', [doc._transaction, doc])
  }
+  let res
  try {
-    f(doc._transaction)
+    res = f(doc._transaction)
  } finally {
    if (initialCall && transactionCleanups[0] === doc._transaction) {
      // The first transaction ended, now process observer calls.
@@ -410,4 +422,5 @@ export const transact = (doc, f, origin = null, local = true) => {
      cleanupTransactions(transactionCleanups, 0)
    }
  }
+  return res
 }
--- a/src/utils/UndoManager.js
+++ b/src/utils/UndoManager.js
@@ -88,7 +88,7 @@ const popStackItem = (undoManager, stack, eventType) => {
        }
      })
      itemsToRedo.forEach(struct => {
-        performedChange = redoItem(transaction, struct, itemsToRedo, stackItem.insertions) !== null || performedChange
+        performedChange = redoItem(transaction, struct, itemsToRedo, itemsToDelete) !== null || performedChange
      })
      // We want to delete in reverse order so that children are deleted before
      // parents, so we have more information available when items are filtered.
@@ -186,7 +186,6 @@ export class UndoManager extends Observable {
        }
      })
      const now = time.getUnixTime()
-      let didAdd = false
      if (now - this.lastChange < captureTimeout && stack.length > 0 && !undoing && !redoing) {
        // append change to last stack op
        const lastOp = stack[stack.length - 1]
@@ -195,7 +194,6 @@ export class UndoManager extends Observable {
      } else {
        // create a new stack op
        stack.push(new StackItem(transaction.deleteSet, insertions))
-        didAdd = true
      }
      if (!undoing && !redoing) {
        this.lastChange = now
@@ -206,9 +204,7 @@ export class UndoManager extends Observable {
          keepItem(item, true)
        }
      })
-      if (didAdd) {
-        this.emit('stack-item-added', [{ stackItem: stack[stack.length - 1], origin: transaction.origin, type: undoing ? 'redo' : 'undo', changedParentTypes: transaction.changedParentTypes }, this])
-      }
+      this.emit('stack-item-added', [{ stackItem: stack[stack.length - 1], origin: transaction.origin, type: undoing ? 'redo' : 'undo', changedParentTypes: transaction.changedParentTypes }, this])
    })
  }

@@ -286,22 +282,4 @@ export class UndoManager extends Observable {
    }
    return res
  }
-
-  /**
-   * Are undo steps available?
-   *
-   * @return {boolean} `true` if undo is possible
-   */
-  canUndo () {
-    return this.undoStack.length > 0
-  }
-
-  /**
-   * Are redo steps available?
-   *
-   * @return {boolean} `true` if redo is possible
-   */
-  canRedo () {
-    return this.redoStack.length > 0
-  }
 }
--- a/src/utils/YEvent.js
+++ b/src/utils/YEvent.js
@@ -1,25 +1,25 @@

 import {
  isDeleted,
-  Item, AbstractType, Transaction, AbstractStruct // eslint-disable-line
+  getMovedCoords,
+  ContentMove, Item, AbstractType, Transaction, AbstractStruct // eslint-disable-line
 } from '../internals.js'

 import * as set from 'lib0/set'
 import * as array from 'lib0/array'

 /**
- * @template {AbstractType<any>} T
 * YEvent describes the changes on a YType.
 */
 export class YEvent {
  /**
-   * @param {T} target The changed type.
+   * @param {AbstractType<any>} target The changed type.
   * @param {Transaction} transaction
   */
  constructor (target, transaction) {
    /**
     * The type on which this event was created on.
-     * @type {T}
+     * @type {AbstractType<any>}
     */
    this.target = target
    /**
@@ -154,62 +154,107 @@ export class YEvent {
  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 = []
-      changes = {
-        added,
-        deleted,
-        delta,
-        keys: this.keys
-      }
-      const changed = /** @type Set<string|null> */ (this.transaction.changed.get(target))
-      if (changed.has(null)) {
+      this.transaction.doc.transact(tr => {
+        const target = this.target
+        const added = set.create()
+        const deleted = set.create()
        /**
-         * @type {any}
+         * @type {Array<{insert:Array<any>}|{delete:number}|{retain:number}>}
         */
-        let lastOp = null
-        const packOp = () => {
-          if (lastOp) {
-            delta.push(lastOp)
-          }
+        const delta = []
+        changes = {
+          added,
+          deleted,
+          delta,
+          keys: this.keys
        }
-        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
+        const changed = /** @type Set<string|null> */ (this.transaction.changed.get(target))
+        if (changed.has(null)) {
+          /**
+           * @type {Array<{ end: Item | null, move: Item | null, isNew : boolean }>}
+           */
+          const movedStack = []
+          /**
+           * @type {Item | null}
+           */
+          let currMove = null
+          /**
+           * @type {boolean}
+           */
+          let currMoveIsNew = false
+          /**
+           * @type {Item | null}
+           */
+          let currMoveEnd = null
+          /**
+           * @type {any}
+           */
+          let lastOp = null
+          const packOp = () => {
+            if (lastOp) {
+              delta.push(lastOp)
            }
          }
+          for (let item = target._start; ;) {
+            if (item === currMoveEnd && currMove) {
+              item = currMove
+              const { end, move, isNew } = movedStack.pop() || { end: null, move: null, isNew: false }
+              currMoveIsNew = isNew
+              currMoveEnd = end
+              currMove = move
+            } else if (item === null) {
+              break
+            } else if (item.content.constructor === ContentMove) {
+              if (item.moved === currMove) {
+                movedStack.push({ end: currMoveEnd, move: currMove, isNew: currMoveIsNew })
+                const { start, end } = getMovedCoords(item.content, tr)
+                currMove = item
+                currMoveEnd = end
+                currMoveIsNew = this.adds(item)
+                item = start
+                continue // do not move to item.right
+              }
+            } else if (item.moved !== currMove) {
+              if (!currMoveIsNew && item.countable && item.moved && !this.adds(item) && this.adds(item.moved) && (this.transaction.prevMoved.get(item) || null) === currMove) {
+                if (lastOp === null || lastOp.delete === undefined) {
+                  packOp()
+                  lastOp = { delete: 0 }
+                }
+                lastOp.delete += item.length
+              }
+            } else if (item.deleted) {
+              if (!currMoveIsNew && this.deletes(item) && !this.adds(item)) {
+                if (lastOp === null || lastOp.delete === undefined) {
+                  packOp()
+                  lastOp = { delete: 0 }
+                }
+                lastOp.delete += item.length
+                deleted.add(item)
+              }
+            } else {
+              if (currMoveIsNew || 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
+              }
+            }
+            item = /** @type {Item} */ (item).right
+          }
+          if (lastOp !== null && lastOp.retain === undefined) {
+            packOp()
+          }
        }
-        if (lastOp !== null && lastOp.retain === undefined) {
-          packOp()
-        }
-      }
-      this._changes = changes
+        this._changes = changes
+      })
    }
    return /** @type {any} */ (changes)
  }
--- a/src/utils/updates.js
+++ b/src/utils/updates.js
@@ -112,30 +112,6 @@ export const logUpdateV2 = (update, YDecoder = UpdateDecoderV2) => {
  logging.print('DeleteSet: ', ds)
 }

-/**
- * @param {Uint8Array} update
- *
- */
-export const decodeUpdate = (update) => decodeUpdateV2(update, UpdateDecoderV1)
-
-/**
- * @param {Uint8Array} update
- * @param {typeof UpdateDecoderV2 | typeof UpdateDecoderV1} [YDecoder]
- *
- */
-export const decodeUpdateV2 = (update, YDecoder = UpdateDecoderV2) => {
-  const structs = []
-  const updateDecoder = new UpdateDecoderV1(decoding.createDecoder(update))
-  const lazyDecoder = new LazyStructReader(updateDecoder, false)
-  for (let curr = lazyDecoder.curr; curr !== null; curr = lazyDecoder.next()) {
-    structs.push(curr)
-  }
-  return {
-    structs,
-    ds: readDeleteSet(updateDecoder)
-  }
-}
-
 export class LazyStructWriter {
  /**
   * @param {UpdateEncoderV1 | UpdateEncoderV2} encoder
@@ -332,6 +308,7 @@ export const mergeUpdatesV2 = (updates, YDecoder = UpdateDecoderV2, YEncoder = U
  // Note: Should handle that some operations cannot be applied yet ()

  while (true) {
+    // @todo this incurs an exponential overhead. We could instead only sort the item that changed.
    // Write higher clients first ⇒ sort by clientID & clock and remove decoders without content
    lazyStructDecoders = lazyStructDecoders.filter(dec => dec.curr !== null)
    lazyStructDecoders.sort(
--- a/tests/doc.tests.js
+++ b/tests/doc.tests.js
@@ -40,6 +40,7 @@ export const testToJSON = tc => {

  const arr = doc.getArray('array')
  arr.push(['test1'])
+  t.compare(arr.toJSON(), ['test1'])

  const map = doc.getMap('map')
  map.set('k1', 'v1')
--- a/tests/encoding.tests.js
+++ b/tests/encoding.tests.js
@@ -12,6 +12,7 @@ import {
  readContentFormat,
  readContentAny,
  readContentDoc,
+  readContentMove,
  Doc,
  PermanentUserData,
  encodeStateAsUpdate,
@@ -24,7 +25,8 @@ import * as Y from '../src/index.js'
 * @param {t.TestCase} tc
 */
 export const testStructReferences = tc => {
-  t.assert(contentRefs.length === 11)
+  t.assert(contentRefs.length === 12)
+  // contentRefs[0] is reserved for GC
  t.assert(contentRefs[1] === readContentDeleted)
  t.assert(contentRefs[2] === readContentJSON) // TODO: deprecate content json?
  t.assert(contentRefs[3] === readContentBinary)
@@ -35,6 +37,7 @@ export const testStructReferences = tc => {
  t.assert(contentRefs[8] === readContentAny)
  t.assert(contentRefs[9] === readContentDoc)
  // contentRefs[10] is reserved for Skip structs
+  t.assert(contentRefs[11] === readContentMove)
 }

 /**
@@ -72,9 +75,9 @@ export const testPermanentUserData = async tc => {
 export const testDiffStateVectorOfUpdateIsEmpty = tc => {
  const ydoc = new Y.Doc()
  /**
-   * @type {any}
+   * @type {null | Uint8Array}
   */
-  let sv = null
+  let sv = /* any */ (null)
  ydoc.getText().insert(0, 'a')
  ydoc.on('update', update => {
    sv = Y.encodeStateVectorFromUpdate(update)
--- a/tests/testHelper.js
+++ b/tests/testHelper.js
@@ -373,6 +373,33 @@ export const compare = users => {
    t.compare(Y.encodeStateVector(users[i]), Y.encodeStateVector(users[i + 1]))
    compareDS(Y.createDeleteSetFromStructStore(users[i].store), Y.createDeleteSetFromStructStore(users[i + 1].store))
    compareStructStores(users[i].store, users[i + 1].store)
+    // @todo
+    // test list-iterator
+    // console.log('dutiraneduiaentdr', users[0].getArray('array')._searchMarker)
+    /*
+    {
+      const user = users[0]
+      user.transact(tr => {
+        const type = user.getArray('array')
+        Y.useSearchMarker(tr, type, type.length, walker => {
+          for (let i = type.length; i >= 0; i--) {
+            const otherWalker = new Y.ListIterator(type)
+            otherWalker.forward(tr, walker.index)
+            otherWalker.forward(tr, 0)
+            walker.forward(tr, 0)
+            t.assert(walker.index === i)
+            t.assert(walker.left === otherWalker.left)
+            t.assert(walker.right === otherWalker.right)
+            t.assert(walker.nextItem === otherWalker.nextItem)
+            t.assert(walker.reachedEnd === otherWalker.reachedEnd)
+            if (i > 0) {
+              walker.backward(tr, 1)
+            }
+          }
+        })
+      })
+    }
+    */
  }
  users.map(u => u.destroy())
 }
--- a/tests/undo-redo.tests.js
+++ b/tests/undo-redo.tests.js
@@ -1,4 +1,4 @@
-import { init, compare, applyRandomTests, Doc } from './testHelper.js' // eslint-disable-line
+import { init, compare, applyRandomTests, Doc, UndoManager } from './testHelper.js' // eslint-disable-line

 import * as Y from '../src/index.js'
 import * as t from 'lib0/testing'
@@ -273,7 +273,7 @@ export const testUndoInEmbed = tc => {
 */
 export const testUndoDeleteFilter = tc => {
  /**
-   * @type {Y.Array<any>}
+   * @type {Array<Y.Map<any>>}
   */
  const array0 = /** @type {any} */ (init(tc, { users: 3 }).array0)
  const undoManager = new Y.UndoManager(array0, { deleteFilter: item => !(item instanceof Y.Item) || (item.content instanceof Y.ContentType && item.content.type._map.size === 0) })
@@ -372,196 +372,3 @@ export const testUndoNestedUndoIssue = tc => {
  undoManager.redo()
  t.compare(design.toJSON(), { text: { blocks: { text: 'Something Else' } } })
 }
-
-/**
- * This issue has been reported in https://github.com/yjs/yjs/issues/355
- *
- * @param {t.TestCase} tc
- */
-export const testConsecutiveRedoBug = tc => {
-  const doc = new Y.Doc()
-  const yRoot = doc.getMap()
-  const undoMgr = new Y.UndoManager(yRoot)
-
-  let yPoint = new Y.Map()
-  yPoint.set('x', 0)
-  yPoint.set('y', 0)
-  yRoot.set('a', yPoint)
-  undoMgr.stopCapturing()
-
-  yPoint.set('x', 100)
-  yPoint.set('y', 100)
-  undoMgr.stopCapturing()
-
-  yPoint.set('x', 200)
-  yPoint.set('y', 200)
-  undoMgr.stopCapturing()
-
-  yPoint.set('x', 300)
-  yPoint.set('y', 300)
-  undoMgr.stopCapturing()
-
-  t.compare(yPoint.toJSON(), { x: 300, y: 300 })
-
-  undoMgr.undo() // x=200, y=200
-  t.compare(yPoint.toJSON(), { x: 200, y: 200 })
-  undoMgr.undo() // x=100, y=100
-  t.compare(yPoint.toJSON(), { x: 100, y: 100 })
-  undoMgr.undo() // x=0, y=0
-  t.compare(yPoint.toJSON(), { x: 0, y: 0 })
-  undoMgr.undo() // nil
-  t.compare(yRoot.get('a'), undefined)
-
-  undoMgr.redo() // x=0, y=0
-  yPoint = yRoot.get('a')
-
-  t.compare(yPoint.toJSON(), { x: 0, y: 0 })
-  undoMgr.redo() // x=100, y=100
-  t.compare(yPoint.toJSON(), { x: 100, y: 100 })
-  undoMgr.redo() // x=200, y=200
-  t.compare(yPoint.toJSON(), { x: 200, y: 200 })
-  undoMgr.redo() // expected x=300, y=300, actually nil
-  t.compare(yPoint.toJSON(), { x: 300, y: 300 })
-}
-
-/**
- * This issue has been reported in https://github.com/yjs/yjs/issues/304
- *
- * @param {t.TestCase} tc
- */
-export const testUndoXmlBug = tc => {
-  const origin = 'origin'
-  const doc = new Y.Doc()
-  const fragment = doc.getXmlFragment('t')
-  const undoManager = new Y.UndoManager(fragment, {
-    captureTimeout: 0,
-    trackedOrigins: new Set([origin])
-  })
-
-  // create element
-  doc.transact(() => {
-    const e = new Y.XmlElement('test-node')
-    e.setAttribute('a', '100')
-    e.setAttribute('b', '0')
-    fragment.insert(fragment.length, [e])
-  }, origin)
-
-  // change one attribute
-  doc.transact(() => {
-    const e = fragment.get(0)
-    e.setAttribute('a', '200')
-  }, origin)
-
-  // change both attributes
-  doc.transact(() => {
-    const e = fragment.get(0)
-    e.setAttribute('a', '180')
-    e.setAttribute('b', '50')
-  }, origin)
-
-  undoManager.undo()
-  undoManager.undo()
-  undoManager.undo()
-
-  undoManager.redo()
-  undoManager.redo()
-  undoManager.redo()
-  t.compare(fragment.toString(), '<test-node a="180" b="50"></test-node>')
-}
-
-/**
- * This issue has been reported in https://github.com/yjs/yjs/issues/343
- *
- * @param {t.TestCase} tc
- */
-export const testUndoBlockBug = tc => {
-  const doc = new Y.Doc({ gc: false })
-  const design = doc.getMap()
-
-  const undoManager = new Y.UndoManager(design, { captureTimeout: 0 })
-
-  const text = new Y.Map()
-
-  const blocks1 = new Y.Array()
-  const blocks1block = new Y.Map()
-  doc.transact(() => {
-    blocks1block.set('text', '1')
-    blocks1.push([blocks1block])
-
-    text.set('blocks', blocks1block)
-    design.set('text', text)
-  })
-
-  const blocks2 = new Y.Array()
-  const blocks2block = new Y.Map()
-  doc.transact(() => {
-    blocks2block.set('text', '2')
-    blocks2.push([blocks2block])
-    text.set('blocks', blocks2block)
-  })
-
-  const blocks3 = new Y.Array()
-  const blocks3block = new Y.Map()
-  doc.transact(() => {
-    blocks3block.set('text', '3')
-    blocks3.push([blocks3block])
-    text.set('blocks', blocks3block)
-  })
-
-  const blocks4 = new Y.Array()
-  const blocks4block = new Y.Map()
-  doc.transact(() => {
-    blocks4block.set('text', '4')
-    blocks4.push([blocks4block])
-    text.set('blocks', blocks4block)
-  })
-
-  // {"text":{"blocks":{"text":"4"}}}
-  undoManager.undo() // {"text":{"blocks":{"3"}}}
-  undoManager.undo() // {"text":{"blocks":{"text":"2"}}}
-  undoManager.undo() // {"text":{"blocks":{"text":"1"}}}
-  undoManager.undo() // {}
-  undoManager.redo() // {"text":{"blocks":{"text":"1"}}}
-  undoManager.redo() // {"text":{"blocks":{"text":"2"}}}
-  undoManager.redo() // {"text":{"blocks":{"text":"3"}}}
-  undoManager.redo() // {"text":{}}
-  t.compare(design.toJSON(), { text: { blocks: { text: '4' } } })
-}
-
-/**
- * Undo text formatting delete should not corrupt peer state.
- *
- * @see https://github.com/yjs/yjs/issues/392
- * @param {t.TestCase} tc
- */
-export const testUndoDeleteTextFormat = tc => {
-  const doc = new Y.Doc()
-  const text = doc.getText()
-  text.insert(0, 'Attack ships on fire off the shoulder of Orion.')
-  const doc2 = new Y.Doc()
-  const text2 = doc2.getText()
-  Y.applyUpdate(doc2, Y.encodeStateAsUpdate(doc))
-  const undoManager = new Y.UndoManager(text)
-
-  text.format(13, 7, { bold: true })
-  undoManager.stopCapturing()
-  Y.applyUpdate(doc2, Y.encodeStateAsUpdate(doc))
-
-  text.format(16, 4, { bold: null })
-  undoManager.stopCapturing()
-  Y.applyUpdate(doc2, Y.encodeStateAsUpdate(doc))
-
-  undoManager.undo()
-  Y.applyUpdate(doc2, Y.encodeStateAsUpdate(doc))
-
-  const expect = [
-    { insert: 'Attack ships ' },
-    {
-      insert: 'on fire',
-      attributes: { bold: true }
-    },
-    { insert: ' off the shoulder of Orion.' }
-  ]
-  t.compare(text.toDelta(), expect)
-  t.compare(text2.toDelta(), expect)
-}
--- a/tests/y-array.tests.js
+++ b/tests/y-array.tests.js
@@ -1,4 +1,4 @@
-import { init, compare, applyRandomTests, Doc } from './testHelper.js' // eslint-disable-line
+import { init, compare, applyRandomTests, Doc, AbstractType, TestConnector } from './testHelper.js' // eslint-disable-line

 import * as Y from '../src/index.js'
 import * as t from 'lib0/testing'
@@ -432,6 +432,86 @@ export const testEventTargetIsSetCorrectlyOnRemote = tc => {
  compare(users)
 }

+/**
+ * @param {t.TestCase} tc
+ */
+export const testMove = tc => {
+  {
+    // move in uninitialized type
+    const yarr = new Y.Array()
+    yarr.insert(0, [1, 2, 3])
+    yarr.move(1, 0)
+    // @ts-ignore
+    t.compare(yarr._prelimContent, [2, 1, 3])
+  }
+  const { array0, array1, users } = init(tc, { users: 3 })
+  /**
+   * @type {any}
+   */
+  let event0 = null
+  /**
+   * @type {any}
+   */
+  let event1 = null
+  array0.observe(event => {
+    event0 = event
+  })
+  array1.observe(event => {
+    event1 = event
+  })
+  array0.insert(0, [1, 2, 3])
+  array0.move(1, 0)
+  t.compare(array0.toArray(), [2, 1, 3])
+  t.compare(event0.delta, [{ insert: [2] }, { retain: 1 }, { delete: 1 }])
+  Y.applyUpdate(users[1], Y.encodeStateAsUpdate(users[0]))
+  t.compare(array1.toArray(), [2, 1, 3])
+  t.compare(event1.delta, [{ insert: [2, 1, 3] }])
+  array0.move(0, 2)
+  t.compare(array0.toArray(), [1, 2, 3])
+  t.compare(event0.delta, [{ delete: 1 }, { retain: 1 }, { insert: [2] }])
+  compare(users)
+}
+
+/**
+ * @param {t.TestCase} tc
+ */
+export const testMove2 = tc => {
+  {
+    // move in uninitialized type
+    const yarr = new Y.Array()
+    yarr.insert(0, [1, 2])
+    yarr.move(1, 0)
+    // @ts-ignore
+    t.compare(yarr._prelimContent, [2, 1])
+  }
+  const { array0, array1, users } = init(tc, { users: 3 })
+  /**
+   * @type {any}
+   */
+  let event0 = null
+  /**
+   * @type {any}
+   */
+  let event1 = null
+  array0.observe(event => {
+    event0 = event
+  })
+  array1.observe(event => {
+    event1 = event
+  })
+  array0.insert(0, [1, 2])
+  array0.move(1, 0)
+  t.compare(array0.toArray(), [2, 1])
+  t.compare(event0.delta, [{ insert: [2] }, { retain: 1 }, { delete: 1 }])
+  Y.applyUpdate(users[1], Y.encodeStateAsUpdate(users[0]))
+  t.compare(array1.toArray(), [2, 1])
+  t.compare(event1.delta, [{ insert: [2, 1] }])
+  array0.move(0, 2)
+  t.compare(array0.toArray(), [1, 2])
+  t.compare(event0.delta, [{ delete: 1 }, { retain: 1 }, { insert: [2] }])
+  compare(users)
+}
+
 /**
 * @param {t.TestCase} tc
 */
@@ -456,8 +536,23 @@ const getUniqueNumber = () => _uniqueNumber++

 /**
 * @type {Array<function(Doc,prng.PRNG,any):void>}
+ *
+ * @todo to replace content to a separate data structure so we know that insert & returns work as expected!!!
 */
 const arrayTransactions = [
+  function move (user, gen) {
+    const yarray = user.getArray('array')
+    if (yarray.length === 0) {
+      return
+    }
+    const pos = prng.int32(gen, 0, yarray.length - 1)
+    const newPos = prng.int32(gen, 0, yarray.length)
+    const oldContent = yarray.toArray()
+    yarray.move(pos, newPos)
+    const [x] = oldContent.splice(pos, 1)
+    oldContent.splice(pos < newPos ? newPos - 1 : newPos, 0, x)
+    t.compareArrays(yarray.toArray(), oldContent) // we want to make sure that fastSearch markers insert at the correct position
+  },
  function insert (user, gen) {
    const yarray = user.getArray('array')
    const uniqueNumber = getUniqueNumber()
@@ -516,11 +611,49 @@ const arrayTransactions = [
  }
 ]

+/**
+ * @param {Y.Doc} user
+ */
+const monitorArrayTestObject = user => {
+  /**
+   * @type {Array<any>}
+   */
+  const arr = []
+  const yarr = user.getArray('array')
+  yarr.observe(event => {
+    let currpos = 0
+    const delta = event.delta
+    for (let i = 0; i < delta.length; i++) {
+      const d = delta[i]
+      if (d.insert != null) {
+        arr.splice(currpos, 0, ...(/** @type {Array<any>} */ (d.insert)))
+        currpos += /** @type {Array<any>} */ (d.insert).length
+      } else if (d.retain != null) {
+        currpos += d.retain
+      } else {
+        arr.splice(currpos, d.delete)
+      }
+    }
+  })
+  return arr
+}
+
+/**
+ * @param {{ testObjects: Array<Array<any>>, users: Array<Y.Doc> }} cmp
+ */
+const compareTestobjects = cmp => {
+  const arrs = cmp.testObjects
+  for (let i = 0; i < arrs.length; i++) {
+    const type = cmp.users[i].getArray('array')
+    t.compareArrays(arrs[i], type.toArray())
+  }
+}
+
 /**
 * @param {t.TestCase} tc
 */
 export const testRepeatGeneratingYarrayTests6 = tc => {
-  applyRandomTests(tc, arrayTransactions, 6)
+  compareTestobjects(applyRandomTests(tc, arrayTransactions, 7, monitorArrayTestObject))
 }

 /**
--- a/tests/y-text.tests.js
+++ b/tests/y-text.tests.js
@@ -6,10 +6,6 @@ import * as math from 'lib0/math'
 const { init, compare } = Y

 /**
- * In this test we are mainly interested in the cleanup behavior and whether the resulting delta makes sense.
- * It is fine if the resulting delta is not minimal. But applying the delta to a rich-text editor should result in a
- * synced document.
- *
 * @param {t.TestCase} tc
 */
 export const testDeltaAfterConcurrentFormatting = tc => {
@@ -18,17 +14,12 @@ export const testDeltaAfterConcurrentFormatting = tc => {
  testConnector.flushAllMessages()
  text0.format(0, 3, { bold: true })
  text1.format(2, 2, { bold: true })
-  /**
-   * @type {any}
-   */
-  const deltas = []
+  let delta = null
  text1.observe(event => {
-    if (event.delta.length > 0) {
-      deltas.push(event.delta)
-    }
+    delta = event.delta
  })
  testConnector.flushAllMessages()
-  t.compare(deltas, [[{ retain: 3, attributes: { bold: true } }, { retain: 2, attributes: { bold: null } }]])
+  t.compare(delta, [])
 }

 /**
@@ -147,28 +138,6 @@ export const testNotMergeEmptyLinesFormat = tc => {
  ])
 }

-/**
- * @param {t.TestCase} tc
- */
-export const testPreserveAttributesThroughDelete = tc => {
-  const ydoc = new Y.Doc()
-  const testText = ydoc.getText('test')
-  testText.applyDelta([
-    { insert: 'Text' },
-    { insert: '\n', attributes: { title: true } },
-    { insert: '\n' }
-  ])
-  testText.applyDelta([
-    { retain: 4 },
-    { delete: 1 },
-    { retain: 1, attributes: { title: true } }
-  ])
-  t.compare(testText.toDelta(), [
-    { insert: 'Text' },
-    { insert: '\n', attributes: { title: true } }
-  ])
-}
-
 /**
 * @param {t.TestCase} tc
 */
@@ -358,6 +327,7 @@ export const testFormattingDeltaUnnecessaryAttributeChange = tc => {
 * @param {t.TestCase} tc
 */
 export const testInsertAndDeleteAtRandomPositions = tc => {
+  // @todo optimize to run at least as fast as previous marker approach
  const N = 100000
  const { text0 } = init(tc, { users: 1 })
  const gen = tc.prng
@@ -583,8 +553,6 @@ export const testSearchMarkerBug1 = tc => {
 }

 /**
- * Reported in https://github.com/yjs/yjs/pull/32
- *
 * @param {t.TestCase} tc
 */
 export const testFormattingBug = async tc => {
@@ -594,7 +562,6 @@ export const testFormattingBug = async tc => {
  text1.insert(0, '\n\n\n')
  text1.format(0, 3, { url: 'http://example.com' })
  ydoc1.getText().format(1, 1, { url: 'http://docs.yjs.dev' })
-  ydoc2.getText().format(1, 1, { url: 'http://docs.yjs.dev' })
  Y.applyUpdate(ydoc2, Y.encodeStateAsUpdate(ydoc1))
  const text2 = ydoc2.getText()
  const expectedResult = [
@@ -607,35 +574,6 @@ export const testFormattingBug = async tc => {
  console.log(text1.toDelta())
 }

-/**
- * Delete formatting should not leave redundant formatting items.
- *
- * @param {t.TestCase} tc
- */
-export const testDeleteFormatting = tc => {
-  const doc = new Y.Doc()
-  const text = doc.getText()
-  text.insert(0, 'Attack ships on fire off the shoulder of Orion.')
-
-  const doc2 = new Y.Doc()
-  const text2 = doc2.getText()
-  Y.applyUpdate(doc2, Y.encodeStateAsUpdate(doc))
-
-  text.format(13, 7, { bold: true })
-  Y.applyUpdate(doc2, Y.encodeStateAsUpdate(doc))
-
-  text.format(16, 4, { bold: null })
-  Y.applyUpdate(doc2, Y.encodeStateAsUpdate(doc))
-
-  const expected = [
-    { insert: 'Attack ships ' },
-    { insert: 'on ', attributes: { bold: true } },
-    { insert: 'fire off the shoulder of Orion.' }
-  ]
-  t.compare(text.toDelta(), expected)
-  t.compare(text2.toDelta(), expected)
-}
-
 // RANDOM TESTS

 let charCounter = 0
Author	SHA1	Message	Date
Kevin Jahns	cc93f346ce	13.6.0-2	2021-12-08 16:12:11 +01:00
Kevin Jahns	d3dcd24ef4	fix various tests	2021-12-08 16:10:49 +01:00
Kevin Jahns	6fc4fbd466	13.6.0-1	2021-12-07 13:54:22 +01:00
Kevin Jahns	53e2c83f86	add meta property to AbstractType	2021-12-07 13:53:28 +01:00
Kevin Jahns	24bca2af43	13.6.0-0	2021-12-07 12:42:32 +01:00
Kevin Jahns	b75682022e	skip tests in preversion (should be handled by np)	2021-12-07 12:41:40 +01:00
Kevin Jahns	3d31ba8759	adding more sanity checkss to yarray.tests	2021-12-07 12:37:03 +01:00
Kevin Jahns	bd47efe0ee	fix all tests	2021-12-06 22:21:55 +01:00
Kevin Jahns	f5781f8366	update searchmarkers after insert correctly	2021-12-06 22:07:46 +01:00
Kevin Jahns	6230abb78c	make sure that markers are correct without reinit	2021-12-06 21:22:18 +01:00
Kevin Jahns	4356d70ed0	reinit search marker after transaction	2021-12-06 21:00:20 +01:00
Kevin Jahns	0948229422	handle nested moves	2021-12-06 15:07:43 +01:00
Kevin Jahns	fc5e36158f	made simple one-time move work	2021-12-06 15:07:43 +01:00
Kevin Jahns	d314c3e1a6	fixed ListIterator.reachedEnd edge case	2021-12-06 15:07:43 +01:00
Kevin Jahns	2a33507c00	fixed pos.rel cases	2021-12-06 15:07:43 +01:00
Kevin Jahns	40c3be1732	fix backwards edge case	2021-12-06 15:07:43 +01:00
Kevin Jahns	4a8ebc31f7	fix listiterator.map returning undefined as the last element	2021-12-06 15:07:43 +01:00
Kevin Jahns	6df152c4ec	proper iteration through arrays (for mappings, toJSON, ..)	2021-12-06 15:07:43 +01:00
Kevin Jahns	fc38f3b848	formatting bug	2021-12-06 15:07:43 +01:00
Kevin Jahns	a057bf1cf0	fix disconnect issue	2021-12-06 15:07:43 +01:00
Kevin Jahns	8b82c573c4	fix basic inserd & delete bug	2021-12-06 15:07:43 +01:00
Kevin Jahns	a77221ffd2	fix toJSON value	2021-12-06 15:07:42 +01:00
Kevin Jahns	b9ccbb2dc7	created new abstraction for search marker	2021-12-06 15:06:17 +01:00
Kevin Jahns	a723c32557	use new ListPosition abstraction in Y.Array .slice and .get	2021-12-06 15:06:17 +01:00
Kevin Jahns	56ab251e79	make moved a separate prop on item	2021-12-06 15:06:17 +01:00
Kevin Jahns	53a7b286b8	Move content and list iteration abstraction	2021-12-06 15:06:13 +01:00