13.2.0

Add 'size' getter to Y.Map

README.md

@@ -40,6 +40,7 @@ height="60px" />](https://input.com/)
 [![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)
+[![Gremloon](https://github.com/gremloon.png?size=60)](https://github.com/gremloon)
 
 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)
 

package-lock.json

@@ -1,6 +1,6 @@
 {
   "name": "yjs",
-  "version": "13.1.1",
+  "version": "13.2.0",
   "lockfileVersion": 1,
   "requires": true,
   "dependencies": {

package.json

@@ -1,6 +1,6 @@
 {
   "name": "yjs",
-  "version": "13.1.1",
+  "version": "13.2.0",
   "description": "Shared Editing Library",
   "main": "./dist/yjs.cjs",
   "module": "./dist/yjs.mjs",

src/structs/AbstractStruct.js

@@ -39,39 +39,9 @@ export class AbstractStruct {
 
   /**
    * @param {Transaction} transaction
-   */
-  integrate (transaction) {
-    throw error.methodUnimplemented()
-  }
-}
-
-export class AbstractStructRef {
-  /**
-   * @param {ID} id
-   */
-  constructor (id) {
-    this.id = id
-    /**
-     * @type {Array<ID>}
-     */
-    this._missing = []
-  }
-
-  /**
-   * @param {Transaction} transaction
-   * @return {Array<ID|null>}
-   */
-  getMissing (transaction) {
-    return this._missing
-  }
-
-  /**
-   * @param {Transaction} transaction
-   * @param {StructStore} store
    * @param {number} offset
-   * @return {AbstractStruct}
    */
-  toStruct (transaction, store, offset) {
+  integrate (transaction, offset) {
     throw error.methodUnimplemented()
   }
 }

src/structs/GC.js

@@ -1,12 +1,10 @@
 
 import {
-  AbstractStructRef,
   AbstractStruct,
   addStruct,
   StructStore, Transaction, ID // eslint-disable-line
 } from '../internals.js'
 
-import * as decoding from 'lib0/decoding.js'
 import * as encoding from 'lib0/encoding.js'
 
 export const structGCRefNumber = 0
@@ -37,8 +35,13 @@ export class GC extends AbstractStruct {
 
   /**
    * @param {Transaction} transaction
+   * @param {number} offset
    */
-  integrate (transaction) {
+  integrate (transaction, offset) {
+    if (offset > 0) {
+      this.id.clock += offset
+      this.length -= offset
+    }
     addStruct(transaction.doc.store, this)
   }
 
@@ -50,39 +53,13 @@ export class GC extends AbstractStruct {
     encoding.writeUint8(encoder, structGCRefNumber)
     encoding.writeVarUint(encoder, this.length - offset)
   }
-}
-
-/**
- * @private
- */
-export class GCRef extends AbstractStructRef {
-  /**
-   * @param {decoding.Decoder} decoder
-   * @param {ID} id
-   * @param {number} info
-   */
-  constructor (decoder, id, info) {
-    super(id)
-    /**
-     * @type {number}
-     */
-    this.length = decoding.readVarUint(decoder)
-  }
 
   /**
    * @param {Transaction} transaction
    * @param {StructStore} store
-   * @param {number} offset
-   * @return {GC}
+   * @return {null | ID}
    */
-  toStruct (transaction, store, offset) {
-    if (offset > 0) {
-      this.id.clock += offset
-      this.length -= offset
-    }
-    return new GC(
-      this.id,
-      this.length
-    )
+  getMissing (transaction, store) {
+    return null
   }
 }

src/structs/Item.js

@@ -4,7 +4,6 @@ import {
   writeID,
   GC,
   getState,
-  AbstractStructRef,
   AbstractStruct,
   replaceStruct,
   addStruct,
@@ -24,7 +23,7 @@ import {
   readContentFormat,
   readContentType,
   addChangedTypeToTransaction,
-  ContentType, ContentDeleted, StructStore, ID, AbstractType, Transaction // eslint-disable-line
+  Doc, ContentType, ContentDeleted, StructStore, ID, AbstractType, Transaction // eslint-disable-line
 } from '../internals.js'
 
 import * as error from 'lib0/error.js'
@@ -73,7 +72,7 @@ export const followRedone = (store, id) => {
 export const keepItem = (item, keep) => {
   while (item !== null && item.keep !== keep) {
     item.keep = keep
-    item = item.parent._item
+    item = /** @type {AbstractType<any>} */ (item.parent)._item
   }
 }
 
@@ -119,7 +118,7 @@ export const splitItem = (transaction, leftItem, diff) => {
   transaction._mergeStructs.push(rightItem)
   // update parent._map
   if (rightItem.parentSub !== null && rightItem.right === null) {
-    rightItem.parent._map.set(rightItem.parentSub, rightItem)
+    /** @type {AbstractType<any>} */ (rightItem.parent)._map.set(rightItem.parentSub, rightItem)
   }
   leftItem.length = diff
   return rightItem
@@ -144,7 +143,7 @@ export const redoItem = (transaction, item, redoitems) => {
   if (redone !== null) {
     return getItemCleanStart(transaction, redone)
   }
-  let parentItem = item.parent._item
+  let parentItem = /** @type {AbstractType<any>} */ (item.parent)._item
   /**
    * @type {Item|null}
    */
@@ -169,7 +168,7 @@ export const redoItem = (transaction, item, redoitems) => {
       }
     }
     if (left.right !== null) {
-      left = /** @type {Item} */ (item.parent._map.get(item.parentSub))
+      left = /** @type {Item} */ (/** @type {AbstractType<any>} */ (item.parent)._map.get(item.parentSub))
     }
     right = null
   }
@@ -191,10 +190,10 @@ export const redoItem = (transaction, item, redoitems) => {
        */
       let leftTrace = left
       // trace redone until parent matches
-      while (leftTrace !== null && leftTrace.parent._item !== parentItem) {
+      while (leftTrace !== null && /** @type {AbstractType<any>} */ (leftTrace.parent)._item !== parentItem) {
         leftTrace = leftTrace.redone === null ? null : getItemCleanStart(transaction, leftTrace.redone)
       }
-      if (leftTrace !== null && leftTrace.parent._item === parentItem) {
+      if (leftTrace !== null && /** @type {AbstractType<any>} */ (leftTrace.parent)._item === parentItem) {
         left = leftTrace
         break
       }
@@ -206,10 +205,10 @@ export const redoItem = (transaction, item, redoitems) => {
        */
       let rightTrace = right
       // trace redone until parent matches
-      while (rightTrace !== null && rightTrace.parent._item !== parentItem) {
+      while (rightTrace !== null && /** @type {AbstractType<any>} */ (rightTrace.parent)._item !== parentItem) {
         rightTrace = rightTrace.redone === null ? null : getItemCleanStart(transaction, rightTrace.redone)
       }
-      if (rightTrace !== null && rightTrace.parent._item === parentItem) {
+      if (rightTrace !== null && /** @type {AbstractType<any>} */ (rightTrace.parent)._item === parentItem) {
         right = rightTrace
         break
       }
@@ -228,7 +227,7 @@ export const redoItem = (transaction, item, redoitems) => {
   )
   item.redone = nextId
   keepItem(redoneItem, true)
-  redoneItem.integrate(transaction)
+  redoneItem.integrate(transaction, 0)
   return redoneItem
 }
 
@@ -242,7 +241,7 @@ export class Item extends AbstractStruct {
    * @param {ID | null} origin
    * @param {Item | null} right
    * @param {ID | null} rightOrigin
-   * @param {AbstractType<any>} parent
+   * @param {AbstractType<any>|ID|null} parent Is a type if integrated, is null if it is possible to copy parent from left or right, is ID before integration to search for it.
    * @param {string | null} parentSub
    * @param {AbstractContent} content
    */
@@ -251,7 +250,6 @@ export class Item extends AbstractStruct {
     /**
      * The item that was originally to the left of this item.
      * @type {ID | null}
-     * @readonly
      */
     this.origin = origin
     /**
@@ -266,14 +264,11 @@ export class Item extends AbstractStruct {
     this.right = right
     /**
      * The item that was originally to the right of this item.
-     * @readonly
      * @type {ID | null}
      */
     this.rightOrigin = rightOrigin
     /**
-     * The parent type.
-     * @type {AbstractType<any>}
-     * @readonly
+     * @type {AbstractType<any>|ID|null}
      */
     this.parent = parent
     /**
@@ -282,7 +277,6 @@ export class Item extends AbstractStruct {
      * to insert this item. If `parentSub = null` type._start is the list in
      * which to insert to. Otherwise it is `parent._map`.
      * @type {String | null}
-     * @readonly
      */
     this.parentSub = parentSub
     /**
@@ -311,104 +305,178 @@ export class Item extends AbstractStruct {
   }
 
   /**
+   * Return missing ids, or define missing items and return null.
+   *
    * @param {Transaction} transaction
+   * @param {StructStore} store
+   * @return {null | ID}
    */
-  integrate (transaction) {
+  getMissing (transaction, store) {
+    const origin = this.origin
+    const rightOrigin = this.rightOrigin
+    const parent = /** @type {ID} */ (this.parent)
+
+    if (origin && origin.clock >= getState(store, origin.client)) {
+      return this.origin
+    }
+    if (rightOrigin && rightOrigin.clock >= getState(store, rightOrigin.client)) {
+      return this.rightOrigin
+    }
+    if (parent && parent.constructor === ID && parent.clock >= getState(store, parent.client)) {
+      return parent
+    }
+
+    // We have all missing ids, now find the items
+
+    if (origin) {
+      this.left = getItemCleanEnd(transaction, store, origin)
+      this.origin = this.left.lastId
+    }
+    if (rightOrigin) {
+      this.right = getItemCleanStart(transaction, rightOrigin)
+      this.rightOrigin = this.right.id
+    }
+    if (parent && parent.constructor === ID) {
+      if (parent.clock < getState(store, parent.client)) {
+        const parentItem = getItem(store, parent)
+        if (parentItem.constructor === GC) {
+          this.parent = null
+        } else {
+          this.parent = /** @type {ContentType} */ (parentItem.content).type
+        }
+      } else {
+        return parent
+      }
+    }
+    // only set item if this shouldn't be garbage collected
+    if (!this.parent) {
+      if (this.left && this.left.constructor === Item) {
+        this.parent = this.left.parent
+        this.parentSub = this.left.parentSub
+      }
+      if (this.right && this.right.constructor === Item) {
+        this.parent = this.right.parent
+        this.parentSub = this.right.parentSub
+      }
+    }
+    return null
+  }
+
+  /**
+   * @param {Transaction} transaction
+   * @param {number} offset
+   */
+  integrate (transaction, offset) {
     const store = transaction.doc.store
-    const parent = this.parent
+    if (offset > 0) {
+      this.id.clock += offset
+      this.left = getItemCleanEnd(transaction, store, createID(this.id.client, this.id.clock - 1))
+      this.origin = this.left.lastId
+      this.content = this.content.splice(offset)
+      this.length -= offset
+    }
     const parentSub = this.parentSub
     const length = this.length
-    /**
-     * @type {Item|null}
-     */
-    let left = this.left
-    /**
-     * @type {Item|null}
-     */
-    let o
-    // set o to the first conflicting item
-    if (left !== null) {
-      o = left.right
-    } else if (parentSub !== null) {
-      o = parent._map.get(parentSub) || null
-      while (o !== null && o.left !== null) {
-        o = o.left
-      }
-    } else {
-      o = parent._start
-    }
-    // TODO: use something like DeleteSet here (a tree implementation would be best)
-    /**
-     * @type {Set<Item>}
-     */
-    const conflictingItems = new Set()
-    /**
-     * @type {Set<Item>}
-     */
-    const itemsBeforeOrigin = new Set()
-    // Let c in conflictingItems, b in itemsBeforeOrigin
-    // ***{origin}bbbb{this}{c,b}{c,b}{o}***
-    // Note that conflictingItems is a subset of itemsBeforeOrigin
-    while (o !== null && o !== this.right) {
-      itemsBeforeOrigin.add(o)
-      conflictingItems.add(o)
-      if (compareIDs(this.origin, o.origin)) {
-        // case 1
-        if (o.id.client < this.id.client) {
-          left = o
-          conflictingItems.clear()
-        }
-      } else if (o.origin !== null && itemsBeforeOrigin.has(getItem(store, o.origin))) {
-        // case 2
-        if (o.origin === null || !conflictingItems.has(getItem(store, o.origin))) {
-          left = o
-          conflictingItems.clear()
-        }
-      } else {
-        break
-      }
-      o = o.right
-    }
-    this.left = left
-    // reconnect left/right + update parent map/start if necessary
-    if (left !== null) {
-      const right = left.right
-      this.right = right
-      left.right = this
-    } else {
-      let r
-      if (parentSub !== null) {
-        r = parent._map.get(parentSub) || null
-        while (r !== null && r.left !== null) {
-          r = r.left
-        }
-      } else {
-        r = parent._start
-        parent._start = this
-      }
-      this.right = r
-    }
-    if (this.right !== null) {
-      this.right.left = this
-    } else if (parentSub !== null) {
-      // set as current parent value if right === null and this is parentSub
-      parent._map.set(parentSub, this)
+    const parent = /** @type {AbstractType<any>|null} */ (this.parent)
+
+    if (parent) {
+      /**
+       * @type {Item|null}
+       */
+      let left = this.left
+
+      /**
+       * @type {Item|null}
+       */
+      let o
+      // set o to the first conflicting item
       if (left !== null) {
-        // this is the current attribute value of parent. delete right
-        left.delete(transaction)
+        o = left.right
+      } else if (parentSub !== null) {
+        o = parent._map.get(parentSub) || null
+        while (o !== null && o.left !== null) {
+          o = o.left
+        }
+      } else {
+        o = parent._start
       }
-    }
-    // adjust length of parent
-    if (parentSub === null && this.countable && !this.deleted) {
-      parent._length += length
-    }
-    addStruct(store, this)
-    this.content.integrate(transaction, this)
-    // add parent to transaction.changed
-    addChangedTypeToTransaction(transaction, parent, parentSub)
-    if ((parent._item !== null && parent._item.deleted) || (this.right !== null && parentSub !== null)) {
-      // delete if parent is deleted or if this is not the current attribute value of parent
-      this.delete(transaction)
+      // TODO: use something like DeleteSet here (a tree implementation would be best)
+      // @todo use global set definitions
+      /**
+       * @type {Set<Item>}
+       */
+      const conflictingItems = new Set()
+      /**
+       * @type {Set<Item>}
+       */
+      const itemsBeforeOrigin = new Set()
+      // Let c in conflictingItems, b in itemsBeforeOrigin
+      // ***{origin}bbbb{this}{c,b}{c,b}{o}***
+      // Note that conflictingItems is a subset of itemsBeforeOrigin
+      while (o !== null && o !== this.right) {
+        itemsBeforeOrigin.add(o)
+        conflictingItems.add(o)
+        if (compareIDs(this.origin, o.origin)) {
+          // case 1
+          if (o.id.client < this.id.client) {
+            left = o
+            conflictingItems.clear()
+          }
+        } else if (o.origin !== null && itemsBeforeOrigin.has(getItem(store, o.origin))) {
+          // case 2
+          if (o.origin === null || !conflictingItems.has(getItem(store, o.origin))) {
+            left = o
+            conflictingItems.clear()
+          }
+        } else {
+          break
+        }
+        o = o.right
+      }
+      this.left = left
+      // reconnect left/right + update parent map/start if necessary
+      if (left !== null) {
+        const right = left.right
+        this.right = right
+        left.right = this
+      } else {
+        let r
+        if (parentSub !== null) {
+          r = parent._map.get(parentSub) || null
+          while (r !== null && r.left !== null) {
+            r = r.left
+          }
+        } else {
+          r = parent._start
+          parent._start = this
+        }
+        this.right = r
+      }
+      if (this.right !== null) {
+        this.right.left = this
+      } else if (parentSub !== null) {
+        // set as current parent value if right === null and this is parentSub
+        parent._map.set(parentSub, this)
+        if (left !== null) {
+          // this is the current attribute value of parent. delete right
+          left.delete(transaction)
+        }
+      }
+      // adjust length of parent
+      if (parentSub === null && this.countable && !this.deleted) {
+        parent._length += length
+      }
+      addStruct(store, this)
+      this.content.integrate(transaction, this)
+      // add parent to transaction.changed
+      addChangedTypeToTransaction(transaction, parent, parentSub)
+      if ((parent._item !== null && parent._item.deleted) || (this.right !== null && parentSub !== null)) {
+        // delete if parent is deleted or if this is not the current attribute value of parent
+        this.delete(transaction)
+      }
+    } else {
+      // parent is not defined. Integrate GC struct instead
+      new GC(this.id, this.length).integrate(transaction, 0)
     }
   }
 
@@ -438,7 +506,8 @@ export class Item extends AbstractStruct {
    * Computes the last content address of this Item.
    */
   get lastId () {
-    return createID(this.id.client, this.id.clock + this.length - 1)
+    // allocating ids is pretty costly because of the amount of ids created, so we try to reuse whenever possible
+    return this.length === 1 ? this.id : createID(this.id.client, this.id.clock + this.length - 1)
   }
 
   /**
@@ -480,7 +549,7 @@ export class Item extends AbstractStruct {
    */
   delete (transaction) {
     if (!this.deleted) {
-      const parent = this.parent
+      const parent = /** @type {AbstractType<any>} */ (this.parent)
       // adjust the length of parent
       if (this.countable && this.parentSub === null) {
         parent._length -= this.length
@@ -533,7 +602,7 @@ export class Item extends AbstractStruct {
       writeID(encoder, rightOrigin)
     }
     if (origin === null && rightOrigin === null) {
-      const parent = this.parent
+      const parent = /** @type {AbstractType<any>} */ (this.parent)
       const parentItem = parent._item
       if (parentItem === null) {
         // parent type on y._map
@@ -669,122 +738,49 @@ export class AbstractContent {
 }
 
 /**
- * @private
+ * @param {decoding.Decoder} decoder
+ * @param {ID} id
+ * @param {number} info
+ * @param {Doc} doc
  */
-export class ItemRef extends AbstractStructRef {
+export const readItem = (decoder, id, info, doc) => {
   /**
-   * @param {decoding.Decoder} decoder
-   * @param {ID} id
-   * @param {number} info
+   * The item that was originally to the left of this item.
+   * @type {ID | null}
    */
-  constructor (decoder, id, info) {
-    super(id)
-    /**
-     * The item that was originally to the left of this item.
-     * @type {ID | null}
-     */
-    this.left = (info & binary.BIT8) === binary.BIT8 ? readID(decoder) : null
-    /**
-     * The item that was originally to the right of this item.
-     * @type {ID | null}
-     */
-    this.right = (info & binary.BIT7) === binary.BIT7 ? readID(decoder) : null
-    const canCopyParentInfo = (info & (binary.BIT7 | binary.BIT8)) === 0
-    const hasParentYKey = canCopyParentInfo ? decoding.readVarUint(decoder) === 1 : false
-    /**
-     * If parent = null and neither left nor right are defined, then we know that `parent` is child of `y`
-     * and we read the next string as parentYKey.
-     * It indicates how we store/retrieve parent from `y.share`
-     * @type {string|null}
-     */
-    this.parentYKey = canCopyParentInfo && hasParentYKey ? decoding.readVarString(decoder) : null
-    /**
-     * The parent type.
-     * @type {ID | null}
-     */
-    this.parent = canCopyParentInfo && !hasParentYKey ? readID(decoder) : null
-    /**
-     * If the parent refers to this item with some kind of key (e.g. YMap, the
-     * key is specified here. The key is then used to refer to the list in which
-     * to insert this item. If `parentSub = null` type._start is the list in
-     * which to insert to. Otherwise it is `parent._map`.
-     * @type {String | null}
-     */
-    this.parentSub = canCopyParentInfo && (info & binary.BIT6) === binary.BIT6 ? decoding.readVarString(decoder) : null
-    const missing = this._missing
-    // Only add items to missing if they don't preceed this item (indicating that it has already been added).
-    // @todo Creating missing items could be done outside this constructor
-    if (this.left !== null && this.left.client !== id.client) {
-      missing.push(this.left)
-    }
-    if (this.right !== null && this.right.client !== id.client) {
-      missing.push(this.right)
-    }
-    if (this.parent !== null) {
-      missing.push(this.parent)
-    }
-    /**
-     * @type {AbstractContent}
-     */
-    this.content = readItemContent(decoder, info)
-    this.length = this.content.getLength()
-  }
+  const origin = (info & binary.BIT8) === binary.BIT8 ? readID(decoder) : null
+  /**
+   * The item that was originally to the right of this item.
+   * @type {ID | null}
+   */
+  const rightOrigin = (info & binary.BIT7) === binary.BIT7 ? readID(decoder) : null
+  const canCopyParentInfo = (info & (binary.BIT7 | binary.BIT8)) === 0
+  const hasParentYKey = canCopyParentInfo ? decoding.readVarUint(decoder) === 1 : false
+  /**
+   * If parent = null and neither left nor right are defined, then we know that `parent` is child of `y`
+   * and we read the next string as parentYKey.
+   * It indicates how we store/retrieve parent from `y.share`
+   * @type {string|null}
+   */
+  const parentYKey = canCopyParentInfo && hasParentYKey ? decoding.readVarString(decoder) : null
+  /**
+   * The parent type.
+   * @type {ID | AbstractType<any> | null}
+   */
+  const parent = canCopyParentInfo && !hasParentYKey ? readID(decoder) : (parentYKey ? doc.get(parentYKey) : null)
+  /**
+   * If the parent refers to this item with some kind of key (e.g. YMap, the
+   * key is specified here. The key is then used to refer to the list in which
+   * to insert this item. If `parentSub = null` type._start is the list in
+   * which to insert to. Otherwise it is `parent._map`.
+   * @type {String | null}
+   */
+  const parentSub = canCopyParentInfo && (info & binary.BIT6) === binary.BIT6 ? decoding.readVarString(decoder) : null
 
   /**
-   * @param {Transaction} transaction
-   * @param {StructStore} store
-   * @param {number} offset
-   * @return {Item|GC}
+   * @type {AbstractContent}
    */
-  toStruct (transaction, store, offset) {
-    if (offset > 0) {
-      this.id.clock += offset
-      this.left = createID(this.id.client, this.id.clock - 1)
-      this.content = this.content.splice(offset)
-      this.length -= offset
-    }
+  const content = readItemContent(decoder, info)
 
-    const left = this.left === null ? null : getItemCleanEnd(transaction, store, this.left)
-    const right = this.right === null ? null : getItemCleanStart(transaction, this.right)
-    const parentId = this.parent
-    let parent = null
-    let parentSub = this.parentSub
-    if (parentId !== null) {
-      const parentItem = getItem(store, parentId)
-      // Edge case: toStruct is called with an offset > 0. In this case left is defined.
-      // Depending in which order structs arrive, left may be GC'd and the parent not
-      // deleted. This is why we check if left is GC'd. Strictly we don't have
-      // to check if right is GC'd, but we will in case we run into future issues
-      if (!parentItem.deleted && (left === null || left.constructor !== GC) && (right === null || right.constructor !== GC)) {
-        parent = /** @type {ContentType} */ (parentItem.content).type
-      }
-    } else if (this.parentYKey !== null) {
-      parent = transaction.doc.get(this.parentYKey)
-    } else if (left !== null) {
-      if (left.constructor !== GC) {
-        parent = left.parent
-        parentSub = left.parentSub
-      }
-    } else if (right !== null) {
-      if (right.constructor !== GC) {
-        parent = right.parent
-        parentSub = right.parentSub
-      }
-    } else {
-      throw error.unexpectedCase()
-    }
-
-    return parent === null
-      ? new GC(this.id, this.length)
-      : new Item(
-        this.id,
-        left,
-        left && left.lastId,
-        right,
-        right && right.id,
-        parent,
-        parentSub,
-        this.content
-      )
-  }
+  return new Item(id, null, origin, null, rightOrigin, parent, parentSub, content)
 }

src/types/AbstractType.js

@@ -53,7 +53,7 @@ export const callTypeObservers = (type, transaction, event) => {
     if (type._item === null) {
       break
     }
-    type = type._item.parent
+    type = /** @type {AbstractType<any>} */ (type._item.parent)
   }
   callEventHandlerListeners(changedType._eH, event, transaction)
 }
@@ -386,7 +386,7 @@ export const typeListInsertGenericsAfter = (transaction, parent, referenceItem,
   const packJsonContent = () => {
     if (jsonContent.length > 0) {
       left = new Item(createID(ownClientId, getState(store, ownClientId)), left, left && left.lastId, right, right && right.id, parent, null, new ContentAny(jsonContent))
-      left.integrate(transaction)
+      left.integrate(transaction, 0)
       jsonContent = []
     }
   }
@@ -405,12 +405,12 @@ export const typeListInsertGenericsAfter = (transaction, parent, referenceItem,
           case Uint8Array:
           case ArrayBuffer:
             left = new Item(createID(ownClientId, getState(store, ownClientId)), left, left && left.lastId, right, right && right.id, parent, null, new ContentBinary(new Uint8Array(/** @type {Uint8Array} */ (c))))
-            left.integrate(transaction)
+            left.integrate(transaction, 0)
             break
           default:
             if (c instanceof AbstractType) {
               left = new Item(createID(ownClientId, getState(store, ownClientId)), left, left && left.lastId, right, right && right.id, parent, null, new ContentType(c))
-              left.integrate(transaction)
+              left.integrate(transaction, 0)
             } else {
               throw new Error('Unexpected content type in insert operation')
             }
@@ -537,7 +537,7 @@ export const typeMapSet = (transaction, parent, key, value) => {
         }
     }
   }
-  new Item(createID(ownClientId, getState(doc.store, ownClientId)), left, left && left.lastId, null, null, parent, key, content).integrate(transaction)
+  new Item(createID(ownClientId, getState(doc.store, ownClientId)), left, left && left.lastId, null, null, parent, key, content).integrate(transaction, 0)
 }
 
 /**

src/types/YMap.js

@@ -45,13 +45,23 @@ export class YMapEvent extends YEvent {
  * @implements {Iterable<T>}
  */
 export class YMap extends AbstractType {
-  constructor () {
+  /**
+   *
+   * @param {Iterable<readonly [string, any]>=} entries - an optional iterable to initialize the YMap
+   */
+  constructor (entries) {
     super()
     /**
      * @type {Map<string,any>?}
      * @private
      */
-    this._prelimContent = new Map()
+    this._prelimContent = null
+
+    if (entries === undefined) {
+      this._prelimContent = new Map()
+    } else {
+      this._prelimContent = new Map(entries)
+    }
   }
 
   /**
@@ -105,6 +115,15 @@ export class YMap extends AbstractType {
     return map
   }
 
+  /**
+   * Returns the size of the YMap (count of key/value pairs)
+   *
+   * @return {number}
+   */
+  get size () {
+    return [...createMapIterator(this._map)].length
+  }
+
   /**
    * Returns the keys for each element in the YMap Type.
    *
@@ -133,7 +152,7 @@ export class YMap extends AbstractType {
   }
 
   /**
-   * Executes a provided function on once on overy key-value pair.
+   * Executes a provided function on once on every key-value pair.
    *
    * @param {function(T,string,YMap<T>):void} f A function to execute on every element of this YArray.
    */

src/types/YText.js

@@ -126,15 +126,14 @@ const findPosition = (transaction, parent, index) => {
  *
  * @param {Transaction} transaction
  * @param {AbstractType<any>} parent
- * @param {Item|null} left
- * @param {Item|null} right
+ * @param {ItemListPosition} currPos
  * @param {Map<string,any>} negatedAttributes
- * @return {ItemListPosition}
  *
  * @private
  * @function
  */
-const insertNegatedAttributes = (transaction, parent, left, right, negatedAttributes) => {
+const insertNegatedAttributes = (transaction, parent, currPos, negatedAttributes) => {
+  let { left, right } = currPos
   // check if we really need to remove attributes
   while (
     right !== null && (
@@ -154,9 +153,10 @@ const insertNegatedAttributes = (transaction, parent, left, right, negatedAttrib
   const ownClientId = doc.clientID
   for (const [key, val] of negatedAttributes) {
     left = new Item(createID(ownClientId, getState(doc.store, ownClientId)), left, left && left.lastId, right, right && right.id, parent, null, new ContentFormat(key, val))
-    left.integrate(transaction)
+    left.integrate(transaction, 0)
   }
-  return { left, right }
+  currPos.left = left
+  currPos.right = right
 }
 
 /**
@@ -176,17 +176,16 @@ const updateCurrentAttributes = (currentAttributes, format) => {
 }
 
 /**
- * @param {Item|null} left
- * @param {Item|null} right
+ * @param {ItemListPosition} currPos
  * @param {Map<string,any>} currentAttributes
  * @param {Object<string,any>} attributes
- * @return {ItemListPosition}
  *
  * @private
  * @function
  */
-const minimizeAttributeChanges = (left, right, currentAttributes, attributes) => {
+const minimizeAttributeChanges = (currPos, currentAttributes, attributes) => {
   // go right while attributes[right.key] === right.value (or right is deleted)
+  let { left, right } = currPos
   while (true) {
     if (right === null) {
       break
@@ -201,22 +200,22 @@ const minimizeAttributeChanges = (left, right, currentAttributes, attributes) =>
     left = right
     right = right.right
   }
-  return new ItemListPosition(left, right)
+  currPos.left = left
+  currPos.right = right
 }
 
 /**
  * @param {Transaction} transaction
  * @param {AbstractType<any>} parent
- * @param {Item|null} left
- * @param {Item|null} right
+ * @param {ItemListPosition} currPos
  * @param {Map<string,any>} currentAttributes
  * @param {Object<string,any>} attributes
- * @return {ItemInsertionResult}
+ * @return {Map<string,any>}
  *
  * @private
  * @function
  **/
-const insertAttributes = (transaction, parent, left, right, currentAttributes, attributes) => {
+const insertAttributes = (transaction, parent, currPos, currentAttributes, attributes) => {
   const doc = transaction.doc
   const ownClientId = doc.clientID
   const negatedAttributes = new Map()
@@ -227,27 +226,26 @@ const insertAttributes = (transaction, parent, left, right, currentAttributes, a
     if (!equalAttrs(currentVal, val)) {
       // save negated attribute (set null if currentVal undefined)
       negatedAttributes.set(key, currentVal)
-      left = new Item(createID(ownClientId, getState(doc.store, ownClientId)), left, left && left.lastId, right, right && right.id, parent, null, new ContentFormat(key, val))
-      left.integrate(transaction)
+      const { left, right } = currPos
+      currPos.left = new Item(createID(ownClientId, getState(doc.store, ownClientId)), left, left && left.lastId, right, right && right.id, parent, null, new ContentFormat(key, val))
+      currPos.left.integrate(transaction, 0)
     }
   }
-  return new ItemInsertionResult(left, right, negatedAttributes)
+  return negatedAttributes
 }
 
 /**
  * @param {Transaction} transaction
  * @param {AbstractType<any>} parent
- * @param {Item|null} left
- * @param {Item|null} right
+ * @param {ItemListPosition} currPos
  * @param {Map<string,any>} currentAttributes
  * @param {string|object} text
  * @param {Object<string,any>} attributes
- * @return {ItemListPosition}
  *
  * @private
  * @function
  **/
-const insertText = (transaction, parent, left, right, currentAttributes, text, attributes) => {
+const insertText = (transaction, parent, currPos, currentAttributes, text, attributes) => {
   for (const [key] of currentAttributes) {
     if (attributes[key] === undefined) {
       attributes[key] = null
@@ -255,38 +253,33 @@ const insertText = (transaction, parent, left, right, currentAttributes, text, a
   }
   const doc = transaction.doc
   const ownClientId = doc.clientID
-  const minPos = minimizeAttributeChanges(left, right, currentAttributes, attributes)
-  const insertPos = insertAttributes(transaction, parent, minPos.left, minPos.right, currentAttributes, attributes)
-  left = insertPos.left
-  right = insertPos.right
+  minimizeAttributeChanges(currPos, currentAttributes, attributes)
+  const negatedAttributes = insertAttributes(transaction, parent, currPos, currentAttributes, attributes)
   // insert content
   const content = text.constructor === String ? new ContentString(/** @type {string} */ (text)) : new ContentEmbed(text)
-  left = new Item(createID(ownClientId, getState(doc.store, ownClientId)), left, left && left.lastId, right, right && right.id, parent, null, content)
-  left.integrate(transaction)
-  return insertNegatedAttributes(transaction, parent, left, insertPos.right, insertPos.negatedAttributes)
+  const { left, right } = currPos
+  currPos.left = new Item(createID(ownClientId, getState(doc.store, ownClientId)), left, left && left.lastId, right, right && right.id, parent, null, content)
+  currPos.left.integrate(transaction, 0)
+  return insertNegatedAttributes(transaction, parent, currPos, negatedAttributes)
 }
 
 /**
  * @param {Transaction} transaction
  * @param {AbstractType<any>} parent
- * @param {Item|null} left
- * @param {Item|null} right
+ * @param {ItemListPosition} currPos
  * @param {Map<string,any>} currentAttributes
  * @param {number} length
  * @param {Object<string,any>} attributes
- * @return {ItemListPosition}
  *
  * @private
  * @function
  */
-const formatText = (transaction, parent, left, right, currentAttributes, length, attributes) => {
+const formatText = (transaction, parent, currPos, currentAttributes, length, attributes) => {
   const doc = transaction.doc
   const ownClientId = doc.clientID
-  const minPos = minimizeAttributeChanges(left, right, currentAttributes, attributes)
-  const insertPos = insertAttributes(transaction, parent, minPos.left, minPos.right, currentAttributes, attributes)
-  const negatedAttributes = insertPos.negatedAttributes
-  left = insertPos.left
-  right = insertPos.right
+  minimizeAttributeChanges(currPos, currentAttributes, attributes)
+  const negatedAttributes = insertAttributes(transaction, parent, currPos, currentAttributes, attributes)
+  let { left, right } = currPos
   // iterate until first non-format or null is found
   // delete all formats with attributes[format.key] != null
   while (length > 0 && right !== null) {
@@ -327,9 +320,11 @@ const formatText = (transaction, parent, left, right, currentAttributes, length,
       newlines += '\n'
     }
     left = new Item(createID(ownClientId, getState(doc.store, ownClientId)), left, left && left.lastId, right, right && right.id, parent, null, new ContentString(newlines))
-    left.integrate(transaction)
+    left.integrate(transaction, 0)
   }
-  return insertNegatedAttributes(transaction, parent, left, right, negatedAttributes)
+  currPos.left = left
+  currPos.right = right
+  insertNegatedAttributes(transaction, parent, currPos, negatedAttributes)
 }
 
 /**
@@ -438,8 +433,7 @@ export const cleanupYTextFormatting = type => {
 
 /**
  * @param {Transaction} transaction
- * @param {Item|null} left
- * @param {Item|null} right
+ * @param {ItemListPosition} currPos
  * @param {Map<string,any>} currentAttributes
  * @param {number} length
  * @return {ItemListPosition}
@@ -447,9 +441,10 @@ export const cleanupYTextFormatting = type => {
  * @private
  * @function
  */
-const deleteText = (transaction, left, right, currentAttributes, length) => {
+const deleteText = (transaction, currPos, currentAttributes, length) => {
   const startAttrs = map.copy(currentAttributes)
-  const start = right
+  const start = currPos.right
+  let { left, right } = currPos
   while (length > 0 && right !== null) {
     if (right.deleted === false) {
       switch (right.content.constructor) {
@@ -472,7 +467,9 @@ const deleteText = (transaction, left, right, currentAttributes, length) => {
   if (start) {
     cleanupFormattingGap(transaction, start, right, startAttrs, map.copy(currentAttributes))
   }
-  return { left, right }
+  currPos.left = left
+  currPos.right = right
+  return currPos
 }
 
 /**
@@ -860,7 +857,7 @@ export class YText extends AbstractType {
         /**
          * @type {ItemListPosition}
          */
-        let pos = new ItemListPosition(null, this._start)
+        const currPos = new ItemListPosition(null, this._start)
         const currentAttributes = new Map()
         for (let i = 0; i < delta.length; i++) {
           const op = delta[i]
@@ -870,14 +867,14 @@ export class YText extends AbstractType {
             // there is a newline at the end of the content.
             // If we omit this step, clients will see a different number of
             // paragraphs, but nothing bad will happen.
-            const ins = (!sanitize && typeof op.insert === 'string' && i === delta.length - 1 && pos.right === null && op.insert.slice(-1) === '\n') ? op.insert.slice(0, -1) : op.insert
+            const ins = (!sanitize && typeof op.insert === 'string' && i === delta.length - 1 && currPos.right === null && op.insert.slice(-1) === '\n') ? op.insert.slice(0, -1) : op.insert
             if (typeof ins !== 'string' || ins.length > 0) {
-              pos = insertText(transaction, this, pos.left, pos.right, currentAttributes, ins, op.attributes || {})
+              insertText(transaction, this, currPos, currentAttributes, ins, op.attributes || {})
             }
           } else if (op.retain !== undefined) {
-            pos = formatText(transaction, this, pos.left, pos.right, currentAttributes, op.retain, op.attributes || {})
+            formatText(transaction, this, currPos, currentAttributes, op.retain, op.attributes || {})
           } else if (op.delete !== undefined) {
-            pos = deleteText(transaction, pos.left, pos.right, currentAttributes, op.delete)
+            deleteText(transaction, currPos, currentAttributes, op.delete)
           }
         }
       })
@@ -1015,7 +1012,7 @@ export class YText extends AbstractType {
           // @ts-ignore
           currentAttributes.forEach((v, k) => { attributes[k] = v })
         }
-        insertText(transaction, this, left, right, currentAttributes, text, attributes)
+        insertText(transaction, this, new ItemListPosition(left, right), currentAttributes, text, attributes)
       })
     } else {
       /** @type {Array<function>} */ (this._pending).push(() => this.insert(index, text, attributes))
@@ -1040,7 +1037,7 @@ export class YText extends AbstractType {
     if (y !== null) {
       transact(y, transaction => {
         const { left, right, currentAttributes } = findPosition(transaction, this, index)
-        insertText(transaction, this, left, right, currentAttributes, embed, attributes)
+        insertText(transaction, this, new ItemListPosition(left, right), currentAttributes, embed, attributes)
       })
     } else {
       /** @type {Array<function>} */ (this._pending).push(() => this.insertEmbed(index, embed, attributes))
@@ -1063,7 +1060,7 @@ export class YText extends AbstractType {
     if (y !== null) {
       transact(y, transaction => {
         const { left, right, currentAttributes } = findPosition(transaction, this, index)
-        deleteText(transaction, left, right, currentAttributes, length)
+        deleteText(transaction, new ItemListPosition(left, right), currentAttributes, length)
       })
     } else {
       /** @type {Array<function>} */ (this._pending).push(() => this.delete(index, length))
@@ -1091,7 +1088,7 @@ export class YText extends AbstractType {
         if (right === null) {
           return
         }
-        formatText(transaction, this, left, right, currentAttributes, length, attributes)
+        formatText(transaction, this, new ItemListPosition(left, right), currentAttributes, length, attributes)
       })
     } else {
       /** @type {Array<function>} */ (this._pending).push(() => this.format(index, length, attributes))

src/types/YXmlFragment.js

@@ -97,7 +97,7 @@ export class YXmlTreeWalker {
             } else if (n.parent === this._root) {
               n = null
             } else {
-              n = n.parent._item
+              n = /** @type {AbstractType<any>} */ (n.parent)._item
             }
           }
         }

src/utils/RelativePosition.js

@@ -227,7 +227,7 @@ export const createAbsolutePositionFromRelativePosition = (rpos, doc) => {
     if (!(right instanceof Item)) {
       return null
     }
-    type = right.parent
+    type = /** @type {AbstractType<any>} */ (right.parent)
     if (type._item === null || !type._item.deleted) {
       index = right.deleted || !right.countable ? 0 : res.diff
       let n = right.left

src/utils/StructStore.js

@@ -2,7 +2,7 @@
 import {
   GC,
   splitItem,
-  AbstractStruct, GCRef, ItemRef, Transaction, ID, Item // eslint-disable-line
+  AbstractStruct, Transaction, ID, Item // eslint-disable-line
 } from '../internals.js'
 
 import * as math from 'lib0/math.js'
@@ -21,13 +21,13 @@ export class StructStore {
      * We could shift the array of refs instead, but shift is incredible
      * slow in Chrome for arrays with more than 100k elements
      * @see tryResumePendingStructRefs
-     * @type {Map<number,{i:number,refs:Array<GCRef|ItemRef>}>}
+     * @type {Map<number,{i:number,refs:Array<GC|Item>}>}
      */
     this.pendingClientsStructRefs = new Map()
     /**
      * Stack of pending structs waiting for struct dependencies
      * Maximum length of stack is structReaders.size
-     * @type {Array<GCRef|ItemRef>}
+     * @type {Array<GC|Item>}
      */
     this.pendingStack = []
     /**
@@ -129,7 +129,10 @@ export const findIndexSS = (structs, clock) => {
   if (mid.id.clock === clock) {
     return right
   }
-  let midindex = math.floor((clock / (midclock + mid.length)) * right) // pivoting the search
+  // @todo does it even make sense to pivot the search?
+  // If a good split misses, it might actually increase the time to find the correct item.
+  // Currently, the only advantage is that search with pivoting might find the item on the first try.
+  let midindex = math.floor((clock / (midclock + mid.length - 1)) * right) // pivoting the search
   while (left <= right) {
     mid = structs[midindex]
     midclock = mid.id.clock

src/utils/Transaction.js

@@ -156,8 +156,8 @@ const tryToMergeWithLeft = (structs, pos) => {
   if (left.deleted === right.deleted && left.constructor === right.constructor) {
     if (left.mergeWith(right)) {
       structs.splice(pos, 1)
-      if (right instanceof Item && right.parentSub !== null && right.parent._map.get(right.parentSub) === right) {
-        right.parent._map.set(right.parentSub, /** @type {Item} */ (left))
+      if (right instanceof Item && right.parentSub !== null && /** @type {AbstractType<any>} */ (right.parent)._map.get(right.parentSub) === right) {
+        /** @type {AbstractType<any>} */ (right.parent)._map.set(right.parentSub, /** @type {Item} */ (left))
       }
     }
   }

src/utils/YEvent.js

@@ -211,7 +211,7 @@ const getPathTo = (parent, child) => {
     } else {
       // parent is array-ish
       let i = 0
-      let c = child._item.parent._start
+      let c = /** @type {AbstractType<any>} */ (child._item.parent)._start
       while (c !== child._item && c !== null) {
         if (!c.deleted) {
           i++
@@ -220,7 +220,7 @@ const getPathTo = (parent, child) => {
       }
       path.unshift(i)
     }
-    child = child._item.parent
+    child = /** @type {AbstractType<any>} */ (child._item.parent)
   }
   return path
 }

src/utils/encoding.js

@@ -16,8 +16,6 @@
 
 import {
   findIndexSS,
-  GCRef,
-  ItemRef,
   writeID,
   readID,
   getState,
@@ -27,6 +25,7 @@ import {
   writeDeleteSet,
   createDeleteSetFromStructStore,
   transact,
+  readItem,
   Doc, Transaction, GC, Item, StructStore, ID // eslint-disable-line
 } from '../internals.js'
 
@@ -80,7 +79,9 @@ export const writeClientsStructs = (encoder, store, _sm) => {
   })
   // write # states that were updated
   encoding.writeVarUint(encoder, sm.size)
-  sm.forEach((clock, client) => {
+  // Write items with higher client ids first
+  // This heavily improves the conflict algorithm.
+  Array.from(sm.entries()).sort((a, b) => b[0] - a[0]).forEach(([client, clock]) => {
     // @ts-ignore
     writeStructs(encoder, store.clients.get(client), client, clock)
   })
@@ -88,13 +89,14 @@ export const writeClientsStructs = (encoder, store, _sm) => {
 
 /**
  * @param {decoding.Decoder} decoder The decoder object to read data from.
- * @param {Map<number,Array<GCRef|ItemRef>>} clientRefs
- * @return {Map<number,Array<GCRef|ItemRef>>}
+ * @param {Map<number,Array<GC|Item>>} clientRefs
+ * @param {Doc} doc
+ * @return {Map<number,Array<GC|Item>>}
  *
  * @private
  * @function
  */
-export const readClientsStructRefs = (decoder, clientRefs) => {
+export const readClientsStructRefs = (decoder, clientRefs, doc) => {
   const numOfStateUpdates = decoding.readVarUint(decoder)
   for (let i = 0; i < numOfStateUpdates; i++) {
     const numberOfStructs = decoding.readVarUint(decoder)
@@ -102,15 +104,16 @@ export const readClientsStructRefs = (decoder, clientRefs) => {
     const nextIdClient = nextID.client
     let nextIdClock = nextID.clock
     /**
-     * @type {Array<GCRef|ItemRef>}
+     * @type {Array<GC|Item>}
      */
     const refs = []
     clientRefs.set(nextIdClient, refs)
     for (let i = 0; i < numberOfStructs; i++) {
       const info = decoding.readUint8(decoder)
-      const ref = (binary.BITS5 & info) === 0 ? new GCRef(decoder, createID(nextIdClient, nextIdClock), info) : new ItemRef(decoder, createID(nextIdClient, nextIdClock), info)
-      refs.push(ref)
-      nextIdClock += ref.length
+      const id = createID(nextIdClient, nextIdClock)
+      const struct = (binary.BITS5 & info) === 0 ? new GC(id, decoding.readVarUint(decoder)) : readItem(decoder, id, info, doc)
+      refs.push(struct)
+      nextIdClock += struct.length
     }
   }
   return clientRefs
@@ -155,12 +158,12 @@ const resumeStructIntegration = (transaction, store) => {
       }
     }
     const ref = stack[stack.length - 1]
-    const m = ref._missing
     const refID = ref.id
     const client = refID.client
     const refClock = refID.clock
     const localClock = getState(store, client)
     const offset = refClock < localClock ? localClock - refClock : 0
+    const missing = ref.getMissing(transaction, store)
     if (refClock + offset !== localClock) {
       // A previous message from this client is missing
       // check if there is a pending structRef with a smaller clock and switch them
@@ -180,27 +183,21 @@ const resumeStructIntegration = (transaction, store) => {
       // wait until missing struct is available
       return
     }
-    while (m.length > 0) {
-      const missing = m[m.length - 1]
-      if (getState(store, missing.client) <= missing.clock) {
-        const client = missing.client
-        // get the struct reader that has the missing struct
-        const structRefs = clientsStructRefs.get(client)
-        if (structRefs === undefined) {
-          // This update message causally depends on another update message.
-          return
-        }
-        stack.push(structRefs.refs[structRefs.i++])
-        if (structRefs.i === structRefs.refs.length) {
-          clientsStructRefs.delete(client)
-        }
-        break
+    if (missing) {
+      const client = missing.client
+      // get the struct reader that has the missing struct
+      const structRefs = clientsStructRefs.get(client)
+      if (structRefs === undefined) {
+        // This update message causally depends on another update message.
+        return
       }
-      ref._missing.pop()
-    }
-    if (m.length === 0) {
+      stack.push(structRefs.refs[structRefs.i++])
+      if (structRefs.i === structRefs.refs.length) {
+        clientsStructRefs.delete(client)
+      }
+    } else {
       if (offset < ref.length) {
-        ref.toStruct(transaction, store, offset).integrate(transaction)
+        ref.integrate(transaction, offset)
       }
       stack.pop()
     }
@@ -233,7 +230,7 @@ export const writeStructsFromTransaction = (encoder, transaction) => writeClient
 
 /**
  * @param {StructStore} store
- * @param {Map<number, Array<GCRef|ItemRef>>} clientsStructsRefs
+ * @param {Map<number, Array<GC|Item>>} clientsStructsRefs
  *
  * @private
  * @function
@@ -270,7 +267,7 @@ const mergeReadStructsIntoPendingReads = (store, clientsStructsRefs) => {
  */
 export const readStructs = (decoder, transaction, store) => {
   const clientsStructRefs = new Map()
-  readClientsStructRefs(decoder, clientsStructRefs)
+  readClientsStructRefs(decoder, clientsStructRefs, transaction.doc)
   mergeReadStructsIntoPendingReads(store, clientsStructRefs)
   resumeStructIntegration(transaction, store)
   tryResumePendingDeleteReaders(transaction, store)

src/utils/isParentOf.js

@@ -16,7 +16,7 @@ export const isParentOf = (parent, child) => {
     if (child.parent === parent) {
       return true
     }
-    child = child.parent._item
+    child = /** @type {AbstractType<any>} */ (child.parent)._item
   }
   return false
 }

tests/y-map.tests.js

@@ -8,6 +8,33 @@ import * as Y from '../src/index.js'
 import * as t from 'lib0/testing.js'
 import * as prng from 'lib0/prng.js'
 
+/**
+ * @param {t.TestCase} tc
+ */
+export const testMapHavingIterableAsConstructorParamTests = tc => {
+  const { map0 } = init(tc, { users: 1 })
+
+  const m1 = new Y.Map(Object.entries({ number: 1, string: 'hello' }))
+  map0.set('m1', m1)
+  t.assert(m1.get('number') === 1)
+  t.assert(m1.get('string') === 'hello')
+
+  const m2 = new Y.Map([
+    ['object', { x: 1 }],
+    ['boolean', true]
+  ])
+  map0.set('m2', m2)
+  t.assert(m2.get('object').x === 1)
+  t.assert(m2.get('boolean') === true)
+
+  const m3 = new Y.Map([...m1, ...m2])
+  map0.set('m3', m3)
+  t.assert(m3.get('number') === 1)
+  t.assert(m3.get('string') === 'hello')
+  t.assert(m3.get('object').x === 1)
+  t.assert(m3.get('boolean') === true)
+}
+
 /**
  * @param {t.TestCase} tc
  */
@@ -33,6 +60,7 @@ export const testBasicMapTests = tc => {
   t.assert(map0.get('boolean1') === true, 'client 0 computed the change (boolean)')
   t.compare(map0.get('object'), { key: { key2: 'value' } }, 'client 0 computed the change (object)')
   t.assert(map0.get('y-map').get('y-array').get(0) === -1, 'client 0 computed the change (type)')
+  t.assert(map0.size === 6, 'client 0 map has correct size')
 
   users[2].connect()
   testConnector.flushAllMessages()
@@ -43,6 +71,7 @@ export const testBasicMapTests = tc => {
   t.assert(map1.get('boolean1') === true, 'client 1 computed the change (boolean)')
   t.compare(map1.get('object'), { key: { key2: 'value' } }, 'client 1 received the update (object)')
   t.assert(map1.get('y-map').get('y-array').get(0) === -1, 'client 1 received the update (type)')
+  t.assert(map1.size === 6, 'client 1 map has correct size')
 
   // compare disconnected user
   t.assert(map2.get('number') === 1, 'client 2 received the update (number) - was disconnected')
@@ -130,6 +159,20 @@ export const testGetAndSetOfMapPropertyWithConflict = tc => {
   compare(users)
 }
 
+/**
+ * @param {t.TestCase} tc
+ */
+export const testSizeAndDeleteOfMapProperty = tc => {
+  const { map0 } = init(tc, { users: 1 })
+  map0.set('stuff', 'c0')
+  map0.set('otherstuff', 'c1')
+  t.assert(map0.size === 2, `map size is ${map0.size} expected 2`)
+  map0.delete('stuff')
+  t.assert(map0.size === 1, `map size after delete is ${map0.size}, expected 1`)
+  map0.delete('otherstuff')
+  t.assert(map0.size === 0, `map size after delete is ${map0.size}, expected 0`)
+}
+
 /**
  * @param {t.TestCase} tc
  */
@@ -454,7 +497,7 @@ const mapTransactions = [
  * @param {t.TestCase} tc
  */
 export const testRepeatGeneratingYmapTests10 = tc => {
-  applyRandomTests(tc, mapTransactions, 10)
+  applyRandomTests(tc, mapTransactions, 3)
 }
 
 /**

tests/y-text.tests.js

@@ -207,20 +207,31 @@ export const testFormattingRemovedInMidText = tc => {
 
 /**
  * @param {t.TestCase} tc
- *
+ */
 export const testLargeFragmentedDocument = tc => {
-  const { text0, text1, testConnector } = init(tc, { users: 2 })
-  // @ts-ignore
-  text0.doc.transact(() => {
-    for (let i = 0; i < 1000000; i++) {
-      text0.insert(0, '0')
-    }
-  })
-  t.measureTime('time to apply', () => {
-    testConnector.flushAllMessages()
-  })
+  const itemsToInsert = 1000000
+  let update = /** @type {any} */ (null)
+  ;(() => {
+    const doc1 = new Y.Doc()
+    const text0 = doc1.getText('txt')
+    t.measureTime(`time to insert ${itemsToInsert}`, () => {
+      doc1.transact(() => {
+        for (let i = 0; i < itemsToInsert; i++) {
+          text0.insert(0, '0')
+        }
+      })
+    })
+    t.measureTime('time to encode', () => {
+      update = Y.encodeStateAsUpdate(doc1)
+    })
+  })()
+  ;(() => {
+    const doc2 = new Y.Doc()
+    t.measureTime('time to apply', () => {
+      Y.applyUpdate(doc2, update)
+    })
+  })()
 }
-*/
 
 // RANDOM TESTS