13.6.5

fix equalDeleteSets

.github/workflows/node.js.yml

@@ -16,7 +16,7 @@ jobs:
 
     strategy:
       matrix:
-        node-version: [10.x, 12.x, 14.x]
+        node-version: [16.x, 18.x]
 
     steps:
     - uses: actions/checkout@v2
@@ -25,5 +25,7 @@ jobs:
       with:
         node-version: ${{ matrix.node-version }}
     - run: npm ci
-    - run: npm run build --if-present
-    - run: npm test
+    - run: npm run lint
+    - run: npm run test-extensive
+      env:
+        CI: true

.github/workflows/nodejs.yml

@@ -1,31 +0,0 @@
-# This workflow will do a clean install of node dependencies, build the source code and run tests across different versions of node
-# For more information see: https://help.github.com/actions/language-and-framework-guides/using-nodejs-with-github-actions
-
-name: Node.js CI
-
-on:
-  push:
-    branches: [ master ]
-  pull_request:
-    branches: [ master ]
-
-jobs:
-  build:
-
-    runs-on: ubuntu-latest
-
-    strategy:
-      matrix:
-        node-version: [10.x, 12.x, 13.x]
-
-    steps:
-    - uses: actions/checkout@v2
-    - name: Use Node.js ${{ matrix.node-version }}
-      uses: actions/setup-node@v1
-      with:
-        node-version: ${{ matrix.node-version }}
-    - run: npm ci
-    - run: npm run lint
-    - run: npm run test-extensive
-      env:
-        CI: true

README.md

@@ -91,6 +91,7 @@ are implemented in separate modules.
 | [CodeMirror](https://codemirror.net/) | ✔ | [y-codemirror](https://github.com/yjs/y-codemirror) | [demo](https://demos.yjs.dev/codemirror/codemirror.html) |
 | [Monaco](https://microsoft.github.io/monaco-editor/) | ✔ | [y-monaco](https://github.com/yjs/y-monaco) | [demo](https://demos.yjs.dev/monaco/monaco.html) |
 | [Slate](https://github.com/ianstormtaylor/slate) | ✔ | [slate-yjs](https://github.com/bitphinix/slate-yjs) | [demo](https://bitphinix.github.io/slate-yjs-example) |
+| [BlockSuite](https://github.com/toeverything/blocksuite) | ✔ | (native) | [demo](https://blocksuite-toeverything.vercel.app/?init) |
 | [valtio](https://github.com/pmndrs/valtio) |  | [valtio-yjs](https://github.com/dai-shi/valtio-yjs) | [demo](https://codesandbox.io/s/valtio-yjs-demo-ox3iy) |
 | [immer](https://github.com/immerjs/immer) |  | [immer-yjs](https://github.com/sep2/immer-yjs) | [demo](https://codesandbox.io/s/immer-yjs-demo-6e0znb) |
 | React / Vue / Svelte / MobX | | [SyncedStore](https://syncedstore.org) | [demo](https://syncedstore.org/docs/react) |
@@ -169,6 +170,9 @@ PORT=1234 node ./node_modules/y-websocket/bin/server.js
 ### Example: Observe types
 
 ```js
+import * as Y from 'yjs';
+
+const doc = new Y.Doc();
 const yarray = doc.getArray('my-array')
 yarray.observe(event => {
   console.log('yarray was modified')
@@ -753,6 +757,30 @@ currentState1 = Y.mergeUpdates([currentState1, diff2])
 currentState1 = Y.mergeUpdates([currentState1, diff1])
 ```
 
+#### Obfuscating Updates
+
+If one of your users runs into a weird bug (e.g. the rich-text editor throws
+error messages), then you don't have to request the full document from your
+user. Instead, they can obfuscate the document (i.e. replace the content with
+meaningless generated content) before sending it to you. Note that someone might
+still deduce the type of content by looking at the general structure of the
+document. But this is much better than requesting the original document.
+
+Obfuscated updates contain all the CRDT-related data that is required for
+merging. So it is safe to merge obfuscated updates.
+
+```javascript
+const ydoc = new Y.Doc()
+// perform some changes..
+ydoc.getText().insert(0, 'hello world')
+const update = Y.encodeStateAsUpdate(ydoc)
+// the below update contains scrambled data
+const obfuscatedUpdate = Y.obfuscateUpdate(update)
+const ydoc2 = new Y.Doc()
+Y.applyUpdate(ydoc2, obfuscatedUpdate)
+ydoc2.getText().toString() // => "00000000000"
+```
+
 #### Using V2 update format
 
 Yjs implements two update formats. By default you are using the V1 update format.

package.json

@@ -1,6 +1,6 @@
 {
   "name": "yjs",
-  "version": "13.5.47",
+  "version": "13.6.5",
   "description": "Shared Editing Library",
   "main": "./dist/yjs.cjs",
   "module": "./dist/yjs.mjs",
@@ -75,19 +75,24 @@
   },
   "homepage": "https://docs.yjs.dev",
   "dependencies": {
-    "lib0": "^0.2.49"
+    "lib0": "^0.2.74"
   },
   "devDependencies": {
-    "@rollup/plugin-commonjs": "^17.0.0",
-    "@rollup/plugin-node-resolve": "^11.2.1",
+    "@rollup/plugin-commonjs": "^24.0.1",
+    "@rollup/plugin-node-resolve": "^15.0.1",
+    "@types/node": "^18.15.5",
     "concurrently": "^3.6.1",
-    "typescript": "^4.9.5",
     "http-server": "^0.12.3",
     "jsdoc": "^3.6.7",
     "markdownlint-cli": "^0.23.2",
-    "rollup": "^2.60.0",
+    "rollup": "^3.20.0",
     "standard": "^16.0.4",
     "tui-jsdoc-template": "^1.2.2",
+    "typescript": "^4.9.5",
     "y-protocols": "^1.0.5"
+  },
+  "engines": {
+    "npm": ">=8.0.0",
+    "node": ">=16.0.0"
   }
 }

rollup.config.js

@@ -42,13 +42,7 @@ export default [{
     name: 'Y',
     file: 'dist/yjs.cjs',
     format: 'cjs',
-    sourcemap: true,
-    paths: path => {
-      if (/^lib0\//.test(path)) {
-        return `lib0/dist/${path.slice(5)}.cjs`
-      }
-      return path
-    }
+    sourcemap: true
   },
   external: id => /^lib0\//.test(id)
 }, {
@@ -88,7 +82,7 @@ export default [{
   plugins: [
     debugResolve,
     nodeResolve({
-      mainFields: ['module', 'browser', 'main']
+      mainFields: ['browser', 'module', 'main']
     }),
     commonjs()
   ]
@@ -103,9 +97,10 @@ export default [{
   plugins: [
     debugResolve,
     nodeResolve({
-      mainFields: ['module', 'main']
+      mainFields: ['node', 'module', 'main'],
+      exportConditions: ['node', 'module', 'import', 'default']
     }),
     commonjs()
   ],
-  external: ['isomorphic.js']
+  external: id => /^lib0\//.test(id)
 }]

src/index.js

@@ -90,7 +90,11 @@ export {
   diffUpdateV2,
   convertUpdateFormatV1ToV2,
   convertUpdateFormatV2ToV1,
-  UpdateEncoderV1
+  obfuscateUpdate,
+  obfuscateUpdateV2,
+  UpdateEncoderV1,
+  equalDeleteSets,
+  snapshotContainsUpdate
 } from './internals.js'
 
 const glo = /** @type {any} */ (typeof globalThis !== 'undefined'

src/structs/Item.js

@@ -23,11 +23,12 @@ import {
   readContentType,
   addChangedTypeToTransaction,
   isDeleted,
-  DeleteSet, UpdateDecoderV1, UpdateDecoderV2, UpdateEncoderV1, UpdateEncoderV2, ContentType, ContentDeleted, StructStore, ID, AbstractType, Transaction // eslint-disable-line
+  StackItem, DeleteSet, 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 * as array from 'lib0/array'
 
 /**
  * @todo This should return several items
@@ -120,6 +121,12 @@ export const splitItem = (transaction, leftItem, diff) => {
   return rightItem
 }
 
+/**
+ * @param {Array<StackItem>} stack
+ * @param {ID} id
+ */
+const isDeletedByUndoStack = (stack, id) => array.some(stack, /** @param {StackItem} s */ s => isDeleted(s.deletions, id))
+
 /**
  * Redoes the effect of this operation.
  *
@@ -128,12 +135,13 @@ export const splitItem = (transaction, leftItem, diff) => {
  * @param {Set<Item>} redoitems
  * @param {DeleteSet} itemsToDelete
  * @param {boolean} ignoreRemoteMapChanges
+ * @param {import('../utils/UndoManager.js').UndoManager} um
  *
  * @return {Item|null}
  *
  * @private
  */
-export const redoItem = (transaction, item, redoitems, itemsToDelete, ignoreRemoteMapChanges) => {
+export const redoItem = (transaction, item, redoitems, itemsToDelete, ignoreRemoteMapChanges, um) => {
   const doc = transaction.doc
   const store = doc.store
   const ownClientID = doc.clientID
@@ -153,7 +161,7 @@ export const redoItem = (transaction, item, redoitems, itemsToDelete, ignoreRemo
   // 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, ignoreRemoteMapChanges) === null)) {
+    if (parentItem.redone === null && (!redoitems.has(parentItem) || redoItem(transaction, parentItem, redoitems, itemsToDelete, ignoreRemoteMapChanges, um) === null)) {
       return null
     }
     while (parentItem.redone !== null) {
@@ -203,13 +211,10 @@ export const redoItem = (transaction, item, redoitems, itemsToDelete, ignoreRemo
       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)) {
+      while (left !== null && left.right !== null && (left.right.redone || isDeleted(itemsToDelete, left.right.id) || isDeletedByUndoStack(um.undoStack, left.right.id) || isDeletedByUndoStack(um.redoStack, left.right.id))) {
         left = left.right
-      }
-      // follow redone
-      // trace redone until parent matches
-      while (left !== null && left.redone !== null) {
-        left = getItemCleanStart(transaction, left.redone)
+        // follow redone
+        while (left.redone) left = getItemCleanStart(transaction, left.redone)
       }
       if (left && left.right !== null) {
         // It is not possible to redo this item because it conflicts with a
@@ -756,48 +761,48 @@ export class AbstractContent {
   }
 
   /**
-   * @param {number} offset
+   * @param {number} _offset
    * @return {AbstractContent}
    */
-  splice (offset) {
+  splice (_offset) {
     throw error.methodUnimplemented()
   }
 
   /**
-   * @param {AbstractContent} right
+   * @param {AbstractContent} _right
    * @return {boolean}
    */
-  mergeWith (right) {
+  mergeWith (_right) {
     throw error.methodUnimplemented()
   }
 
   /**
-   * @param {Transaction} transaction
-   * @param {Item} item
+   * @param {Transaction} _transaction
+   * @param {Item} _item
    */
-  integrate (transaction, item) {
+  integrate (_transaction, _item) {
     throw error.methodUnimplemented()
   }
 
   /**
-   * @param {Transaction} transaction
+   * @param {Transaction} _transaction
    */
-  delete (transaction) {
+  delete (_transaction) {
     throw error.methodUnimplemented()
   }
 
   /**
-   * @param {StructStore} store
+   * @param {StructStore} _store
    */
-  gc (store) {
+  gc (_store) {
     throw error.methodUnimplemented()
   }
 
   /**
-   * @param {UpdateEncoderV1 | UpdateEncoderV2} encoder
-   * @param {number} offset
+   * @param {UpdateEncoderV1 | UpdateEncoderV2} _encoder
+   * @param {number} _offset
    */
-  write (encoder, offset) {
+  write (_encoder, _offset) {
     throw error.methodUnimplemented()
   }
 

src/types/YArray.js

@@ -244,7 +244,7 @@ export class YArray extends AbstractType {
   }
 
   /**
-   * Executes a provided function on once on overy element of this YArray.
+   * Executes a provided function once on overy element of this YArray.
    *
    * @param {function(T,number,YArray<T>):void} f A function to execute on every element of this YArray.
    */

src/types/YMap.js

@@ -206,9 +206,11 @@ export class YMap extends AbstractType {
 
   /**
    * Adds or updates an element with a specified key and value.
+   * @template {MapType} VAL
    *
    * @param {string} key The key of the element to add to this YMap
-   * @param {MapType} value The value of the element to add
+   * @param {VAL} value The value of the element to add
+   * @return {VAL}
    */
   set (key, value) {
     if (this.doc !== null) {

src/types/YText.js

@@ -363,19 +363,26 @@ const formatText = (transaction, parent, currPos, length, attributes) => {
  * @function
  */
 const cleanupFormattingGap = (transaction, start, curr, startAttributes, currAttributes) => {
-  let end = curr
-  const endAttributes = map.copy(currAttributes)
+  /**
+   * @type {Item|null}
+   */
+  let end = start
+  /**
+   * @type {Map<string,ContentFormat>}
+   */
+  const endFormats = map.create()
   while (end && (!end.countable || end.deleted)) {
     if (!end.deleted && end.content.constructor === ContentFormat) {
-      updateCurrentAttributes(endAttributes, /** @type {ContentFormat} */ (end.content))
+      const cf = /** @type {ContentFormat} */ (end.content)
+      endFormats.set(cf.key, cf)
     }
     end = end.right
   }
   let cleanups = 0
-  let reachedEndOfCurr = false
+  let reachedCurr = false
   while (start !== end) {
     if (curr === start) {
-      reachedEndOfCurr = true
+      reachedCurr = true
     }
     if (!start.deleted) {
       const content = start.content
@@ -383,11 +390,11 @@ const cleanupFormattingGap = (transaction, start, curr, startAttributes, currAtt
         case ContentFormat: {
           const { key, value } = /** @type {ContentFormat} */ (content)
           const startAttrValue = startAttributes.get(key) || null
-          if ((endAttributes.get(key) || null) !== value || startAttrValue === value) {
+          if (endFormats.get(key) !== content || startAttrValue === value) {
             // Either this format is overwritten or it is not necessary because the attribute already existed.
             start.delete(transaction)
             cleanups++
-            if (!reachedEndOfCurr && (currAttributes.get(key) || null) === value && (startAttributes.get(key) || null) !== value) {
+            if (!reachedCurr && (currAttributes.get(key) || null) === value && startAttrValue !== value) {
               if (startAttrValue === null) {
                 currAttributes.delete(key)
               } else {
@@ -395,6 +402,9 @@ const cleanupFormattingGap = (transaction, start, curr, startAttributes, currAtt
               }
             }
           }
+          if (!reachedCurr && !start.deleted) {
+            updateCurrentAttributes(currAttributes, /** @type {ContentFormat} */ (content))
+          }
           break
         }
       }
@@ -466,6 +476,56 @@ export const cleanupYTextFormatting = type => {
   return res
 }
 
+/**
+ * This will be called by the transction once the event handlers are called to potentially cleanup
+ * formatting attributes.
+ *
+ * @param {Transaction} transaction
+ */
+export const cleanupYTextAfterTransaction = transaction => {
+  /**
+   * @type {Set<YText>}
+   */
+  const needFullCleanup = new Set()
+  // check if another formatting item was inserted
+  const doc = transaction.doc
+  for (const [client, afterClock] of transaction.afterState.entries()) {
+    const clock = transaction.beforeState.get(client) || 0
+    if (afterClock === clock) {
+      continue
+    }
+    iterateStructs(transaction, /** @type {Array<Item|GC>} */ (doc.store.clients.get(client)), clock, afterClock, item => {
+      if (
+        !item.deleted && /** @type {Item} */ (item).content.constructor === ContentFormat && item.constructor !== GC
+      ) {
+        needFullCleanup.add(/** @type {any} */ (item).parent)
+      }
+    })
+  }
+  // cleanup in a new transaction
+  transact(doc, (t) => {
+    iterateDeletedStructs(transaction, transaction.deleteSet, item => {
+      if (item instanceof GC || needFullCleanup.has(/** @type {YText} */ (item.parent))) {
+        return
+      }
+      const parent = /** @type {YText} */ (item.parent)
+      if (item.content.constructor === ContentFormat) {
+        needFullCleanup.add(parent)
+      } else {
+        // If no formatting attribute was inserted or deleted, we can make due with contextless
+        // formatting cleanups.
+        // Contextless: it is not necessary to compute currentAttributes for the affected position.
+        cleanupContextlessFormattingGap(t, item)
+      }
+    })
+    // If a formatting item was inserted, we simply clean the whole type.
+    // We need to compute currentAttributes for the current position anyway.
+    for (const yText of needFullCleanup) {
+      cleanupYTextFormatting(yText)
+    }
+  })
+}
+
 /**
  * @param {Transaction} transaction
  * @param {ItemTextListPosition} currPos
@@ -621,36 +681,39 @@ export class YTextEvent extends YEvent {
             /**
              * @type {any}
              */
-            let op
+            let op = null
             switch (action) {
               case 'delete':
-                op = { delete: deleteLen }
+                if (deleteLen > 0) {
+                  op = { delete: deleteLen }
+                }
                 deleteLen = 0
                 break
               case 'insert':
-                op = { insert }
-                if (currentAttributes.size > 0) {
-                  op.attributes = {}
-                  currentAttributes.forEach((value, key) => {
-                    if (value !== null) {
-                      op.attributes[key] = value
-                    }
-                  })
+                if (typeof insert === 'object' || insert.length > 0) {
+                  op = { insert }
+                  if (currentAttributes.size > 0) {
+                    op.attributes = {}
+                    currentAttributes.forEach((value, key) => {
+                      if (value !== null) {
+                        op.attributes[key] = value
+                      }
+                    })
+                  }
                 }
                 insert = ''
                 break
               case 'retain':
-                op = { retain }
-                if (Object.keys(attributes).length > 0) {
-                  op.attributes = {}
-                  for (const key in attributes) {
-                    op.attributes[key] = attributes[key]
+                if (retain > 0) {
+                  op = { retain }
+                  if (!object.isEmpty(attributes)) {
+                    op.attributes = object.assign({}, attributes)
                   }
                 }
                 retain = 0
                 break
             }
-            delta.push(op)
+            if (op) delta.push(op)
             action = null
           }
         }
@@ -846,55 +909,10 @@ export class YText extends AbstractType {
   _callObserver (transaction, parentSubs) {
     super._callObserver(transaction, parentSubs)
     const event = new YTextEvent(this, transaction, parentSubs)
-    const doc = transaction.doc
     callTypeObservers(this, transaction, event)
     // If a remote change happened, we try to cleanup potential formatting duplicates.
     if (!transaction.local) {
-      // check if another formatting item was inserted
-      let foundFormattingItem = false
-      for (const [client, afterClock] of transaction.afterState.entries()) {
-        const clock = transaction.beforeState.get(client) || 0
-        if (afterClock === clock) {
-          continue
-        }
-        iterateStructs(transaction, /** @type {Array<Item|GC>} */ (doc.store.clients.get(client)), clock, afterClock, item => {
-          if (!item.deleted && /** @type {Item} */ (item).content.constructor === ContentFormat) {
-            foundFormattingItem = true
-          }
-        })
-        if (foundFormattingItem) {
-          break
-        }
-      }
-      if (!foundFormattingItem) {
-        iterateDeletedStructs(transaction, transaction.deleteSet, item => {
-          if (item instanceof GC || foundFormattingItem) {
-            return
-          }
-          if (item.parent === this && item.content.constructor === ContentFormat) {
-            foundFormattingItem = true
-          }
-        })
-      }
-      transact(doc, (t) => {
-        if (foundFormattingItem) {
-          // If a formatting item was inserted, we simply clean the whole type.
-          // We need to compute currentAttributes for the current position anyway.
-          cleanupYTextFormatting(this)
-        } else {
-          // If no formatting attribute was inserted, we can make due with contextless
-          // formatting cleanups.
-          // Contextless: it is not necessary to compute currentAttributes for the affected position.
-          iterateDeletedStructs(t, t.deleteSet, item => {
-            if (item instanceof GC) {
-              return
-            }
-            if (item.parent === this) {
-              cleanupContextlessFormattingGap(t, item)
-            }
-          })
-        }
-      })
+      transaction._needFormattingCleanup = true
     }
   }
 
@@ -1008,15 +1026,7 @@ export class YText extends AbstractType {
         str = ''
       }
     }
-    // snapshots are merged again after the transaction, so we need to keep the
-    // transalive until we are done
-    transact(doc, transaction => {
-      if (snapshot) {
-        splitSnapshotAffectedStructs(transaction, snapshot)
-      }
-      if (prevSnapshot) {
-        splitSnapshotAffectedStructs(transaction, prevSnapshot)
-      }
+    const computeDelta = () => {
       while (n !== null) {
         if (isVisible(n, snapshot) || (prevSnapshot !== undefined && isVisible(n, prevSnapshot))) {
           switch (n.content.constructor) {
@@ -1069,7 +1079,22 @@ export class YText extends AbstractType {
         n = n.right
       }
       packStr()
-    }, 'cleanup')
+    }
+    if (snapshot || prevSnapshot) {
+      // snapshots are merged again after the transaction, so we need to keep the
+      // transaction alive until we are done
+      transact(doc, transaction => {
+        if (snapshot) {
+          splitSnapshotAffectedStructs(transaction, snapshot)
+        }
+        if (prevSnapshot) {
+          splitSnapshotAffectedStructs(transaction, prevSnapshot)
+        }
+        computeDelta()
+      }, 'cleanup')
+    } else {
+      computeDelta()
+    }
     return ops
   }
 

src/types/YXmlElement.js

@@ -1,3 +1,4 @@
+import * as object from 'lib0/object'
 
 import {
   YXmlFragment,
@@ -12,12 +13,18 @@ import {
   YXmlText, ContentType, AbstractType, UpdateDecoderV1, UpdateDecoderV2, UpdateEncoderV1, UpdateEncoderV2, Doc, Item // eslint-disable-line
 } from '../internals.js'
 
+/**
+ * @typedef {Object|number|null|Array<any>|string|Uint8Array|AbstractType<any>} ValueTypes
+ */
+
 /**
  * An YXmlElement imitates the behavior of a
  * {@link https://developer.mozilla.org/en-US/docs/Web/API/Element|Dom Element}.
  *
  * * An YXmlElement has attributes (key value pairs)
  * * An YXmlElement has childElements that must inherit from YXmlElement
+ *
+ * @template {{ [key: string]: ValueTypes }} [KV={ [key: string]: string }]
  */
 export class YXmlElement extends YXmlFragment {
   constructor (nodeName = 'UNDEFINED') {
@@ -73,14 +80,19 @@ export class YXmlElement extends YXmlFragment {
   }
 
   /**
-   * @return {YXmlElement}
+   * @return {YXmlElement<KV>}
    */
   clone () {
+    /**
+     * @type {YXmlElement<KV>}
+     */
     const el = new YXmlElement(this.nodeName)
     const attrs = this.getAttributes()
-    for (const key in attrs) {
-      el.setAttribute(key, attrs[key])
-    }
+    object.forEach(attrs, (value, key) => {
+      if (typeof value === 'string') {
+        el.setAttribute(key, value)
+      }
+    })
     // @ts-ignore
     el.insert(0, this.toArray().map(item => item instanceof AbstractType ? item.clone() : item))
     return el
@@ -116,7 +128,7 @@ export class YXmlElement extends YXmlFragment {
   /**
    * Removes an attribute from this YXmlElement.
    *
-   * @param {String} attributeName The attribute name that is to be removed.
+   * @param {string} attributeName The attribute name that is to be removed.
    *
    * @public
    */
@@ -133,8 +145,10 @@ export class YXmlElement extends YXmlFragment {
   /**
    * Sets or updates an attribute.
    *
-   * @param {String} attributeName The attribute name that is to be set.
-   * @param {String} attributeValue The attribute value that is to be set.
+   * @template {keyof KV & string} KEY
+   *
+   * @param {KEY} attributeName The attribute name that is to be set.
+   * @param {KV[KEY]} attributeValue The attribute value that is to be set.
    *
    * @public
    */
@@ -151,9 +165,11 @@ export class YXmlElement extends YXmlFragment {
   /**
    * Returns an attribute value that belongs to the attribute name.
    *
-   * @param {String} attributeName The attribute name that identifies the
+   * @template {keyof KV & string} KEY
+   *
+   * @param {KEY} attributeName The attribute name that identifies the
    *                               queried value.
-   * @return {String} The queried attribute value.
+   * @return {KV[KEY]|undefined} The queried attribute value.
    *
    * @public
    */
@@ -164,7 +180,7 @@ export class YXmlElement extends YXmlFragment {
   /**
    * Returns whether an attribute exists
    *
-   * @param {String} attributeName The attribute name to check for existence.
+   * @param {string} attributeName The attribute name to check for existence.
    * @return {boolean} whether the attribute exists.
    *
    * @public
@@ -176,12 +192,12 @@ export class YXmlElement extends YXmlFragment {
   /**
    * Returns all attribute name/value pairs in a JSON Object.
    *
-   * @return {Object<string, any>} A JSON Object that describes the attributes.
+   * @return {{ [Key in Extract<keyof KV,string>]?: KV[Key]}} A JSON Object that describes the attributes.
    *
    * @public
    */
   getAttributes () {
-    return typeMapGetAll(this)
+    return /** @type {any} */ (typeMapGetAll(this))
   }
 
   /**
@@ -203,7 +219,10 @@ export class YXmlElement extends YXmlFragment {
     const dom = _document.createElement(this.nodeName)
     const attrs = this.getAttributes()
     for (const key in attrs) {
-      dom.setAttribute(key, attrs[key])
+      const value = attrs[key]
+      if (typeof value === 'string') {
+        dom.setAttribute(key, value)
+      }
     }
     typeListForEach(this, yxml => {
       dom.appendChild(yxml.toDOM(_document, hooks, binding))

src/utils/DeleteSet.js

@@ -171,7 +171,7 @@ export const mergeDeleteSets = dss => {
  * @function
  */
 export const addToDeleteSet = (ds, client, clock, length) => {
-  map.setIfUndefined(ds.clients, client, () => []).push(new DeleteItem(clock, length))
+  map.setIfUndefined(ds.clients, client, () => /** @type {Array<DeleteItem>} */ ([])).push(new DeleteItem(clock, length))
 }
 
 export const createDeleteSet = () => new DeleteSet()
@@ -251,7 +251,7 @@ export const readDeleteSet = decoder => {
     const client = decoding.readVarUint(decoder.restDecoder)
     const numberOfDeletes = decoding.readVarUint(decoder.restDecoder)
     if (numberOfDeletes > 0) {
-      const dsField = map.setIfUndefined(ds.clients, client, () => [])
+      const dsField = map.setIfUndefined(ds.clients, client, () => /** @type {Array<DeleteItem>} */ ([]))
       for (let i = 0; i < numberOfDeletes; i++) {
         dsField.push(new DeleteItem(decoder.readDsClock(), decoder.readDsLen()))
       }
@@ -328,3 +328,23 @@ export const readAndApplyDeleteSet = (decoder, transaction, store) => {
   }
   return null
 }
+
+/**
+ * @param {DeleteSet} ds1
+ * @param {DeleteSet} ds2
+ */
+export const equalDeleteSets = (ds1, ds2) => {
+  if (ds1.clients.size !== ds2.clients.size) return false
+  for (const [client, deleteItems1] of ds1.clients.entries()) {
+    const deleteItems2 = /** @type {Array<import('../internals.js').DeleteItem>} */ (ds2.clients.get(client))
+    if (deleteItems2 === undefined || deleteItems1.length !== deleteItems2.length) return false
+    for (let i = 0; i < deleteItems1.length; i++) {
+      const di1 = deleteItems1[i]
+      const di2 = deleteItems2[i]
+      if (di1.clock !== di2.clock || di1.len !== di2.len) {
+        return false
+      }
+    }
+  }
+  return true
+}

src/utils/Doc.js

@@ -156,13 +156,15 @@ export class Doc extends Observable {
    * that happened inside of the transaction are sent as one message to the
    * other peers.
    *
-   * @param {function(Transaction):void} f The function that should be executed as a transaction
+   * @template T
+   * @param {function(Transaction):T} f The function that should be executed as a transaction
    * @param {any} [origin] Origin of who started the transaction. Will be stored on transaction.origin
+   * @return T
    *
    * @public
    */
   transact (f, origin = null) {
-    transact(this, f, origin)
+    return transact(this, f, origin)
   }
 
   /**

src/utils/Snapshot.js

@@ -15,7 +15,10 @@ import {
   findIndexSS,
   UpdateEncoderV2,
   applyUpdateV2,
-  DSEncoderV1, DSEncoderV2, DSDecoderV1, DSDecoderV2, Transaction, Doc, DeleteSet, Item // eslint-disable-line
+  LazyStructReader,
+  equalDeleteSets,
+  UpdateDecoderV1, UpdateDecoderV2, DSEncoderV1, DSEncoderV2, DSDecoderV1, DSDecoderV2, Transaction, Doc, DeleteSet, Item, // eslint-disable-line
+  mergeDeleteSets
 } from '../internals.js'
 
 import * as map from 'lib0/map'
@@ -147,12 +150,20 @@ export const splitSnapshotAffectedStructs = (transaction, snapshot) => {
         getItemCleanStart(transaction, createID(client, clock))
       }
     })
-    iterateDeletedStructs(transaction, snapshot.ds, item => {})
+    iterateDeletedStructs(transaction, snapshot.ds, _item => {})
     meta.add(snapshot)
   }
 }
 
 /**
+ * @example
+ *  const ydoc = new Y.Doc({ gc: false })
+ *  ydoc.getText().insert(0, 'world!')
+ *  const snapshot = Y.snapshot(ydoc)
+ *  ydoc.getText().insert(0, 'hello ')
+ *  const restored = Y.createDocFromSnapshot(ydoc, snapshot)
+ *  assert(restored.getText().toString() === 'world!')
+ *
  * @param {Doc} originDoc
  * @param {Snapshot} snapshot
  * @param {Doc} [newDoc] Optionally, you may define the Yjs document that receives the data from originDoc
@@ -161,7 +172,7 @@ export const splitSnapshotAffectedStructs = (transaction, snapshot) => {
 export const createDocFromSnapshot = (originDoc, snapshot, newDoc = new Doc()) => {
   if (originDoc.gc) {
     // we should not try to restore a GC-ed document, because some of the restored items might have their content deleted
-    throw new Error('originDoc must not be garbage collected')
+    throw new Error('Garbage-collection must be disabled in `originDoc`!')
   }
   const { sv, ds } = snapshot
 
@@ -199,3 +210,28 @@ export const createDocFromSnapshot = (originDoc, snapshot, newDoc = new Doc()) =
   applyUpdateV2(newDoc, encoder.toUint8Array(), 'snapshot')
   return newDoc
 }
+
+/**
+ * @param {Snapshot} snapshot
+ * @param {Uint8Array} update
+ * @param {typeof UpdateDecoderV2 | typeof UpdateDecoderV1} [YDecoder]
+ */
+export const snapshotContainsUpdateV2 = (snapshot, update, YDecoder = UpdateDecoderV2) => {
+  const structs = []
+  const updateDecoder = new YDecoder(decoding.createDecoder(update))
+  const lazyDecoder = new LazyStructReader(updateDecoder, false)
+  for (let curr = lazyDecoder.curr; curr !== null; curr = lazyDecoder.next()) {
+    structs.push(curr)
+    if ((snapshot.sv.get(curr.id.client) || 0) < curr.id.clock + curr.length) {
+      return false
+    }
+  }
+  const mergedDS = mergeDeleteSets([snapshot.ds, readDeleteSet(updateDecoder)])
+  return equalDeleteSets(snapshot.ds, mergedDS)
+}
+
+/**
+ * @param {Snapshot} snapshot
+ * @param {Uint8Array} update
+ */
+export const snapshotContainsUpdate = (snapshot, update) => snapshotContainsUpdateV2(snapshot, update, UpdateDecoderV1)

src/utils/Transaction.js

@@ -11,6 +11,7 @@ import {
   Item,
   generateNewClientId,
   createID,
+  cleanupYTextAfterTransaction,
   UpdateEncoderV1, UpdateEncoderV2, GC, StructStore, AbstractType, AbstractStruct, YEvent, Doc // eslint-disable-line
 } from '../internals.js'
 
@@ -114,6 +115,10 @@ export class Transaction {
      * @type {Set<Doc>}
      */
     this.subdocsLoaded = new Set()
+    /**
+     * @type {boolean}
+     */
+    this._needFormattingCleanup = false
   }
 }
 
@@ -270,31 +275,34 @@ const cleanupTransactions = (transactionCleanups, i) => {
       )
       fs.push(() => {
         // deep observe events
-        transaction.changedParentTypes.forEach((events, type) =>
-          fs.push(() => {
-            // We need to think about the possibility that the user transforms the
-            // Y.Doc in the event.
-            if (type._item === null || !type._item.deleted) {
-              events = events
-                .filter(event =>
-                  event.target._item === null || !event.target._item.deleted
-                )
-              events
-                .forEach(event => {
-                  event.currentTarget = type
-                })
-              // sort events by path length so that top-level events are fired first.
-              events
-                .sort((event1, event2) => event1.path.length - event2.path.length)
-              // We don't need to check for events.length
-              // because we know it has at least one element
-              callEventHandlerListeners(type._dEH, events, transaction)
-            }
-          })
-        )
-        fs.push(() => doc.emit('afterTransaction', [transaction, doc]))
+        transaction.changedParentTypes.forEach((events, type) => {
+          // We need to think about the possibility that the user transforms the
+          // Y.Doc in the event.
+          if (type._dEH.l.length > 0 && (type._item === null || !type._item.deleted)) {
+            events = events
+              .filter(event =>
+                event.target._item === null || !event.target._item.deleted
+              )
+            events
+              .forEach(event => {
+                event.currentTarget = type
+                // path is relative to the current target
+                event._path = null
+              })
+            // sort events by path length so that top-level events are fired first.
+            events
+              .sort((event1, event2) => event1.path.length - event2.path.length)
+            // We don't need to check for events.length
+            // because we know it has at least one element
+            callEventHandlerListeners(type._dEH, events, transaction)
+          }
+        })
       })
+      fs.push(() => doc.emit('afterTransaction', [transaction, doc]))
       callAll(fs, [])
+      if (transaction._needFormattingCleanup) {
+        cleanupYTextAfterTransaction(transaction)
+      }
     } finally {
       // Replace deleted items with ItemDeleted / GC.
       // This is where content is actually remove from the Yjs Doc.
@@ -376,15 +384,21 @@ 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
  */
 export const transact = (doc, f, origin = null, local = true) => {
   const transactionCleanups = doc._transactionCleanups
   let initialCall = false
+  /**
+   * @type {any}
+   */
+  let result = null
   if (doc._transaction === null) {
     initialCall = true
     doc._transaction = new Transaction(doc, origin, local)
@@ -395,7 +409,7 @@ export const transact = (doc, f, origin = null, local = true) => {
     doc.emit('beforeTransaction', [doc._transaction, doc])
   }
   try {
-    f(doc._transaction)
+    result = f(doc._transaction)
   } finally {
     if (initialCall) {
       const finishCleanup = doc._transaction === transactionCleanups[0]
@@ -413,4 +427,5 @@ export const transact = (doc, f, origin = null, local = true) => {
       }
     }
   }
+  return result
 }

src/utils/UndoManager.js

@@ -10,14 +10,14 @@ import {
   getItemCleanStart,
   isDeleted,
   addToDeleteSet,
-  Transaction, Doc, Item, GC, DeleteSet, AbstractType, YEvent // eslint-disable-line
+  Transaction, Doc, Item, GC, DeleteSet, AbstractType // eslint-disable-line
 } from '../internals.js'
 
 import * as time from 'lib0/time'
 import * as array from 'lib0/array'
 import { Observable } from 'lib0/observable'
 
-class StackItem {
+export class StackItem {
   /**
    * @param {DeleteSet} deletions
    * @param {DeleteSet} insertions
@@ -101,7 +101,7 @@ const popStackItem = (undoManager, stack, eventType) => {
         }
       })
       itemsToRedo.forEach(struct => {
-        performedChange = redoItem(transaction, struct, itemsToRedo, stackItem.insertions, undoManager.ignoreRemoteMapChanges) !== null || performedChange
+        performedChange = redoItem(transaction, struct, itemsToRedo, stackItem.insertions, undoManager.ignoreRemoteMapChanges, undoManager) !== 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.
@@ -158,7 +158,7 @@ export class UndoManager extends Observable {
    */
   constructor (typeScope, {
     captureTimeout = 500,
-    captureTransaction = tr => true,
+    captureTransaction = _tr => true,
     deleteFilter = () => true,
     trackedOrigins = new Set([null]),
     ignoreRemoteMapChanges = false,

src/utils/YEvent.js

@@ -44,6 +44,10 @@ export class YEvent {
      * @type {null | Array<{ insert?: string | Array<any> | object | AbstractType<any>, retain?: number, delete?: number, attributes?: Object<string, any> }>}
      */
     this._delta = null
+    /**
+     * @type {Array<string|number>|null}
+     */
+    this._path = null
   }
 
   /**
@@ -60,8 +64,7 @@ export class YEvent {
    *   type === event.target // => true
    */
   get path () {
-    // @ts-ignore _item is defined because target is integrated
-    return getPathTo(this.currentTarget, this.target)
+    return this._path || (this._path = getPathTo(this.currentTarget, this.target))
   }
 
   /**
@@ -130,6 +133,11 @@ export class YEvent {
   }
 
   /**
+   * This is a computed property. Note that this can only be safely computed during the
+   * event call. Computing this property after other changes happened might result in
+   * unexpected behavior (incorrect computation of deltas). A safe way to collect changes
+   * is to store the `changes` or the `delta` object. Avoid storing the `transaction` object.
+   *
    * @type {Array<{insert?: string | Array<any> | object | AbstractType<any>, retain?: number, delete?: number, attributes?: Object<string, any>}>}
    */
   get delta () {
@@ -149,6 +157,11 @@ export class YEvent {
   }
 
   /**
+   * This is a computed property. Note that this can only be safely computed during the
+   * event call. Computing this property after other changes happened might result in
+   * unexpected behavior (incorrect computation of deltas). A safe way to collect changes
+   * is to store the `changes` or the `delta` object. Avoid storing the `transaction` object.
+   *
    * @type {{added:Set<Item>,deleted:Set<Item>,keys:Map<string,{action:'add'|'update'|'delete',oldValue:any}>,delta:Array<{insert?:Array<any>|string, delete?:number, retain?:number}>}}
    */
   get changes () {

src/utils/encoding.js

@@ -88,7 +88,7 @@ export const writeClientsStructs = (encoder, store, _sm) => {
       sm.set(client, clock)
     }
   })
-  getStateVector(store).forEach((clock, client) => {
+  getStateVector(store).forEach((_clock, client) => {
     if (!_sm.has(client)) {
       sm.set(client, 0)
     }
@@ -98,8 +98,7 @@ export const writeClientsStructs = (encoder, store, _sm) => {
   // 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)
+    writeStructs(encoder, /** @type {Array<GC|Item>} */ (store.clients.get(client)), client, clock)
   })
 }
 

src/utils/updates.js

@@ -2,19 +2,40 @@
 import * as binary from 'lib0/binary'
 import * as decoding from 'lib0/decoding'
 import * as encoding from 'lib0/encoding'
+import * as error from 'lib0/error'
+import * as f from 'lib0/function'
 import * as logging from 'lib0/logging'
+import * as map from 'lib0/map'
 import * as math from 'lib0/math'
+import * as string from 'lib0/string'
+
 import {
+  ContentAny,
+  ContentBinary,
+  ContentDeleted,
+  ContentDoc,
+  ContentEmbed,
+  ContentFormat,
+  ContentJSON,
+  ContentString,
+  ContentType,
   createID,
-  readItemContent,
-  readDeleteSet,
-  writeDeleteSet,
-  Skip,
-  mergeDeleteSets,
+  decodeStateVector,
   DSEncoderV1,
   DSEncoderV2,
-  decodeStateVector,
-  Item, GC, UpdateDecoderV1, UpdateDecoderV2, UpdateEncoderV1, UpdateEncoderV2 // eslint-disable-line
+  GC,
+  Item,
+  mergeDeleteSets,
+  readDeleteSet,
+  readItemContent,
+  Skip,
+  UpdateDecoderV1,
+  UpdateDecoderV2,
+  UpdateEncoderV1,
+  UpdateEncoderV2,
+  writeDeleteSet,
+  YXmlElement,
+  YXmlHook
 } from '../internals.js'
 
 /**
@@ -552,17 +573,17 @@ const finishLazyStructWriting = (lazyWriter) => {
 
 /**
  * @param {Uint8Array} update
+ * @param {function(Item|GC|Skip):Item|GC|Skip} blockTransformer
  * @param {typeof UpdateDecoderV2 | typeof UpdateDecoderV1} YDecoder
  * @param {typeof UpdateEncoderV2 | typeof UpdateEncoderV1 } YEncoder
  */
-export const convertUpdateFormat = (update, YDecoder, YEncoder) => {
+export const convertUpdateFormat = (update, blockTransformer, YDecoder, YEncoder) => {
   const updateDecoder = new YDecoder(decoding.createDecoder(update))
   const lazyDecoder = new LazyStructReader(updateDecoder, false)
   const updateEncoder = new YEncoder()
   const lazyWriter = new LazyStructWriter(updateEncoder)
-
   for (let curr = lazyDecoder.curr; curr !== null; curr = lazyDecoder.next()) {
-    writeStructToLazyStructWriter(lazyWriter, curr, 0)
+    writeStructToLazyStructWriter(lazyWriter, blockTransformer(curr), 0)
   }
   finishLazyStructWriting(lazyWriter)
   const ds = readDeleteSet(updateDecoder)
@@ -571,11 +592,132 @@ export const convertUpdateFormat = (update, YDecoder, YEncoder) => {
 }
 
 /**
- * @param {Uint8Array} update
+ * @typedef {Object} ObfuscatorOptions
+ * @property {boolean} [ObfuscatorOptions.formatting=true]
+ * @property {boolean} [ObfuscatorOptions.subdocs=true]
+ * @property {boolean} [ObfuscatorOptions.yxml=true] Whether to obfuscate nodeName / hookName
  */
-export const convertUpdateFormatV1ToV2 = update => convertUpdateFormat(update, UpdateDecoderV1, UpdateEncoderV2)
+
+/**
+ * @param {ObfuscatorOptions} obfuscator
+ */
+const createObfuscator = ({ formatting = true, subdocs = true, yxml = true } = {}) => {
+  let i = 0
+  const mapKeyCache = map.create()
+  const nodeNameCache = map.create()
+  const formattingKeyCache = map.create()
+  const formattingValueCache = map.create()
+  formattingValueCache.set(null, null) // end of a formatting range should always be the end of a formatting range
+  /**
+   * @param {Item|GC|Skip} block
+   * @return {Item|GC|Skip}
+   */
+  return block => {
+    switch (block.constructor) {
+      case GC:
+      case Skip:
+        return block
+      case Item: {
+        const item = /** @type {Item} */ (block)
+        const content = item.content
+        switch (content.constructor) {
+          case ContentDeleted:
+            break
+          case ContentType: {
+            if (yxml) {
+              const type = /** @type {ContentType} */ (content).type
+              if (type instanceof YXmlElement) {
+                type.nodeName = map.setIfUndefined(nodeNameCache, type.nodeName, () => 'node-' + i)
+              }
+              if (type instanceof YXmlHook) {
+                type.hookName = map.setIfUndefined(nodeNameCache, type.hookName, () => 'hook-' + i)
+              }
+            }
+            break
+          }
+          case ContentAny: {
+            const c = /** @type {ContentAny} */ (content)
+            c.arr = c.arr.map(() => i)
+            break
+          }
+          case ContentBinary: {
+            const c = /** @type {ContentBinary} */ (content)
+            c.content = new Uint8Array([i])
+            break
+          }
+          case ContentDoc: {
+            const c = /** @type {ContentDoc} */ (content)
+            if (subdocs) {
+              c.opts = {}
+              c.doc.guid = i + ''
+            }
+            break
+          }
+          case ContentEmbed: {
+            const c = /** @type {ContentEmbed} */ (content)
+            c.embed = {}
+            break
+          }
+          case ContentFormat: {
+            const c = /** @type {ContentFormat} */ (content)
+            if (formatting) {
+              c.key = map.setIfUndefined(formattingKeyCache, c.key, () => i + '')
+              c.value = map.setIfUndefined(formattingValueCache, c.value, () => ({ i }))
+            }
+            break
+          }
+          case ContentJSON: {
+            const c = /** @type {ContentJSON} */ (content)
+            c.arr = c.arr.map(() => i)
+            break
+          }
+          case ContentString: {
+            const c = /** @type {ContentString} */ (content)
+            c.str = string.repeat((i % 10) + '', c.str.length)
+            break
+          }
+          default:
+            // unknown content type
+            error.unexpectedCase()
+        }
+        if (item.parentSub) {
+          item.parentSub = map.setIfUndefined(mapKeyCache, item.parentSub, () => i + '')
+        }
+        i++
+        return block
+      }
+      default:
+        // unknown block-type
+        error.unexpectedCase()
+    }
+  }
+}
+
+/**
+ * This function obfuscates the content of a Yjs update. This is useful to share
+ * buggy Yjs documents while significantly limiting the possibility that a
+ * developer can on the user. Note that it might still be possible to deduce
+ * some information by analyzing the "structure" of the document or by analyzing
+ * the typing behavior using the CRDT-related metadata that is still kept fully
+ * intact.
+ *
+ * @param {Uint8Array} update
+ * @param {ObfuscatorOptions} [opts]
+ */
+export const obfuscateUpdate = (update, opts) => convertUpdateFormat(update, createObfuscator(opts), UpdateDecoderV1, UpdateEncoderV1)
+
+/**
+ * @param {Uint8Array} update
+ * @param {ObfuscatorOptions} [opts]
+ */
+export const obfuscateUpdateV2 = (update, opts) => convertUpdateFormat(update, createObfuscator(opts), UpdateDecoderV2, UpdateEncoderV2)
 
 /**
  * @param {Uint8Array} update
  */
-export const convertUpdateFormatV2ToV1 = update => convertUpdateFormat(update, UpdateDecoderV2, UpdateEncoderV1)
+export const convertUpdateFormatV1ToV2 = update => convertUpdateFormat(update, f.id, UpdateDecoderV1, UpdateEncoderV2)
+
+/**
+ * @param {Uint8Array} update
+ */
+export const convertUpdateFormatV2ToV1 = update => convertUpdateFormat(update, f.id, UpdateDecoderV2, UpdateEncoderV1)

tests/doc.tests.js

@@ -2,6 +2,24 @@
 import * as Y from '../src/index.js'
 import * as t from 'lib0/testing'
 
+/**
+ * @param {t.TestCase} _tc
+ */
+export const testAfterTransactionRecursion = _tc => {
+  const ydoc = new Y.Doc()
+  const yxml = ydoc.getXmlFragment('')
+  ydoc.on('afterTransaction', tr => {
+    if (tr.origin === 'test') {
+      yxml.toJSON()
+    }
+  })
+  ydoc.transact(_tr => {
+    for (let i = 0; i < 15000; i++) {
+      yxml.push([new Y.XmlText('a')])
+    }
+  }, 'test')
+}
+
 /**
  * @param {t.TestCase} _tc
  */
@@ -15,7 +33,7 @@ export const testOriginInTransaction = _tc => {
   doc.on('afterTransaction', (tr) => {
     origins.push(tr.origin)
     if (origins.length <= 1) {
-      ytext.toDelta()
+      ytext.toDelta(Y.snapshot(doc)) // adding a snapshot forces toDelta to create a cleanup transaction
       doc.transact(() => {
         ytext.insert(0, 'a')
       }, 'nested')

tests/index.js

@@ -1,3 +1,4 @@
+/* eslint-env node */
 
 import * as map from './y-map.tests.js'
 import * as array from './y-array.tests.js'

tests/snapshot.tests.js

@@ -3,9 +3,21 @@ import * as t from 'lib0/testing'
 import { init } from './testHelper.js'
 
 /**
- * @param {t.TestCase} tc
+ * @param {t.TestCase} _tc
  */
-export const testBasicRestoreSnapshot = tc => {
+export const testBasic = _tc => {
+  const ydoc = new Y.Doc({ gc: false })
+  ydoc.getText().insert(0, 'world!')
+  const snapshot = Y.snapshot(ydoc)
+  ydoc.getText().insert(0, 'hello ')
+  const restored = Y.createDocFromSnapshot(ydoc, snapshot)
+  t.assert(restored.getText().toString() === 'world!')
+}
+
+/**
+ * @param {t.TestCase} _tc
+ */
+export const testBasicRestoreSnapshot = _tc => {
   const doc = new Y.Doc({ gc: false })
   doc.getArray('array').insert(0, ['hello'])
   const snap = Y.snapshot(doc)
@@ -18,9 +30,9 @@ export const testBasicRestoreSnapshot = tc => {
 }
 
 /**
- * @param {t.TestCase} tc
+ * @param {t.TestCase} _tc
  */
-export const testEmptyRestoreSnapshot = tc => {
+export const testEmptyRestoreSnapshot = _tc => {
   const doc = new Y.Doc({ gc: false })
   const snap = Y.snapshot(doc)
   snap.sv.set(9999, 0)
@@ -38,9 +50,9 @@ export const testEmptyRestoreSnapshot = tc => {
 }
 
 /**
- * @param {t.TestCase} tc
+ * @param {t.TestCase} _tc
  */
-export const testRestoreSnapshotWithSubType = tc => {
+export const testRestoreSnapshotWithSubType = _tc => {
   const doc = new Y.Doc({ gc: false })
   doc.getArray('array').insert(0, [new Y.Map()])
   const subMap = doc.getArray('array').get(0)
@@ -61,9 +73,9 @@ export const testRestoreSnapshotWithSubType = tc => {
 }
 
 /**
- * @param {t.TestCase} tc
+ * @param {t.TestCase} _tc
  */
-export const testRestoreDeletedItem1 = tc => {
+export const testRestoreDeletedItem1 = _tc => {
   const doc = new Y.Doc({ gc: false })
   doc.getArray('array').insert(0, ['item1', 'item2'])
 
@@ -77,9 +89,9 @@ export const testRestoreDeletedItem1 = tc => {
 }
 
 /**
- * @param {t.TestCase} tc
+ * @param {t.TestCase} _tc
  */
-export const testRestoreLeftItem = tc => {
+export const testRestoreLeftItem = _tc => {
   const doc = new Y.Doc({ gc: false })
   doc.getArray('array').insert(0, ['item1'])
   doc.getMap('map').set('test', 1)
@@ -95,9 +107,9 @@ export const testRestoreLeftItem = tc => {
 }
 
 /**
- * @param {t.TestCase} tc
+ * @param {t.TestCase} _tc
  */
-export const testDeletedItemsBase = tc => {
+export const testDeletedItemsBase = _tc => {
   const doc = new Y.Doc({ gc: false })
   doc.getArray('array').insert(0, ['item1'])
   doc.getArray('array').delete(0)
@@ -111,9 +123,9 @@ export const testDeletedItemsBase = tc => {
 }
 
 /**
- * @param {t.TestCase} tc
+ * @param {t.TestCase} _tc
  */
-export const testDeletedItems2 = tc => {
+export const testDeletedItems2 = _tc => {
   const doc = new Y.Doc({ gc: false })
   doc.getArray('array').insert(0, ['item1', 'item2', 'item3'])
   doc.getArray('array').delete(1)
@@ -169,3 +181,28 @@ export const testDependentChanges = tc => {
   const docRestored1 = Y.createDocFromSnapshot(array1.doc, snap)
   t.compare(docRestored1.getArray('array').toArray(), ['user1item1', 'user2item1'])
 }
+
+/**
+ * @param {t.TestCase} _tc
+ */
+export const testContainsUpdate = _tc => {
+  const ydoc = new Y.Doc()
+  /**
+   * @type {Array<Uint8Array>}
+   */
+  const updates = []
+  ydoc.on('update', update => {
+    updates.push(update)
+  })
+  const yarr = ydoc.getArray()
+  const snapshot1 = Y.snapshot(ydoc)
+  yarr.insert(0, [1])
+  const snapshot2 = Y.snapshot(ydoc)
+  yarr.delete(0, 1)
+  const snapshotFinal = Y.snapshot(ydoc)
+  t.assert(!Y.snapshotContainsUpdate(snapshot1, updates[0]))
+  t.assert(!Y.snapshotContainsUpdate(snapshot2, updates[1]))
+  t.assert(Y.snapshotContainsUpdate(snapshot2, updates[0]))
+  t.assert(Y.snapshotContainsUpdate(snapshotFinal, updates[0]))
+  t.assert(Y.snapshotContainsUpdate(snapshotFinal, updates[1]))
+}

tests/testHelper.js

@@ -134,7 +134,7 @@ export class TestYInstance extends Y.Doc {
    * @param {TestYInstance} remoteClient
    */
   _receive (message, remoteClient) {
-    map.setIfUndefined(this.receiving, remoteClient, () => []).push(message)
+    map.setIfUndefined(this.receiving, remoteClient, () => /** @type {Array<Uint8Array>} */ ([])).push(message)
   }
 }
 
@@ -347,7 +347,7 @@ export const compare = users => {
     t.compare(userMapValues[i], userMapValues[i + 1])
     t.compare(userXmlValues[i], userXmlValues[i + 1])
     t.compare(userTextValues[i].map(/** @param {any} a */ a => typeof a.insert === 'string' ? a.insert : ' ').join('').length, users[i].getText('text').length)
-    t.compare(userTextValues[i], userTextValues[i + 1], '', (constructor, a, b) => {
+    t.compare(userTextValues[i], userTextValues[i + 1], '', (_constructor, a, b) => {
       if (a instanceof Y.AbstractType) {
         t.compare(a.toJSON(), b.toJSON())
       } else if (a !== b) {
@@ -356,8 +356,9 @@ export const compare = users => {
       return true
     })
     t.compare(Y.encodeStateVector(users[i]), Y.encodeStateVector(users[i + 1]))
-    compareDS(Y.createDeleteSetFromStructStore(users[i].store), Y.createDeleteSetFromStructStore(users[i + 1].store))
+    Y.equalDeleteSets(Y.createDeleteSetFromStructStore(users[i].store), Y.createDeleteSetFromStructStore(users[i + 1].store))
     compareStructStores(users[i].store, users[i + 1].store)
+    t.compare(Y.encodeSnapshot(Y.snapshot(users[i])), Y.encodeSnapshot(Y.snapshot(users[i + 1])))
   }
   users.map(u => u.destroy())
 }
@@ -370,8 +371,8 @@ export const compare = users => {
 export const compareItemIDs = (a, b) => a === b || (a !== null && b != null && Y.compareIDs(a.id, b.id))
 
 /**
- * @param {import('../src/internals').StructStore} ss1
- * @param {import('../src/internals').StructStore} ss2
+ * @param {import('../src/internals.js').StructStore} ss1
+ * @param {import('../src/internals.js').StructStore} ss2
  */
 export const compareStructStores = (ss1, ss2) => {
   t.assert(ss1.clients.size === ss2.clients.size)
@@ -412,25 +413,6 @@ export const compareStructStores = (ss1, ss2) => {
   }
 }
 
-/**
- * @param {import('../src/internals').DeleteSet} ds1
- * @param {import('../src/internals').DeleteSet} ds2
- */
-export const compareDS = (ds1, ds2) => {
-  t.assert(ds1.clients.size === ds2.clients.size)
-  ds1.clients.forEach((deleteItems1, client) => {
-    const deleteItems2 = /** @type {Array<import('../src/internals').DeleteItem>} */ (ds2.clients.get(client))
-    t.assert(deleteItems2 !== undefined && deleteItems1.length === deleteItems2.length)
-    for (let i = 0; i < deleteItems1.length; i++) {
-      const di1 = deleteItems1[i]
-      const di2 = deleteItems2[i]
-      if (di1.clock !== di2.clock || di1.len !== di2.len) {
-        t.fail('DeleteSets dont match')
-      }
-    }
-  })
-}
-
 /**
  * @template T
  * @callback InitTestObjectCallback

tests/undo-redo.tests.js

@@ -1,4 +1,4 @@
-import { init, compare, applyRandomTests, Doc } from './testHelper.js' // eslint-disable-line
+import { init } from './testHelper.js' // eslint-disable-line
 
 import * as Y from '../src/index.js'
 import * as t from 'lib0/testing'
@@ -64,9 +64,9 @@ export const testUndoText = tc => {
 
 /**
  * Test case to fix #241
- * @param {t.TestCase} tc
+ * @param {t.TestCase} _tc
  */
-export const testEmptyTypeScope = tc => {
+export const testEmptyTypeScope = _tc => {
   const ydoc = new Y.Doc()
   const um = new Y.UndoManager([], { doc: ydoc })
   const yarray = ydoc.getArray()
@@ -78,9 +78,9 @@ export const testEmptyTypeScope = tc => {
 
 /**
  * Test case to fix #241
- * @param {t.TestCase} tc
+ * @param {t.TestCase} _tc
  */
-export const testDoubleUndo = tc => {
+export const testDoubleUndo = _tc => {
   const doc = new Y.Doc()
   const text = doc.getText()
   text.insert(0, '1221')
@@ -316,9 +316,9 @@ export const testUndoDeleteFilter = tc => {
 
 /**
  * This issue has been reported in https://discuss.yjs.dev/t/undomanager-with-external-updates/454/6
- * @param {t.TestCase} tc
+ * @param {t.TestCase} _tc
  */
-export const testUndoUntilChangePerformed = tc => {
+export const testUndoUntilChangePerformed = _tc => {
   const doc = new Y.Doc()
   const doc2 = new Y.Doc()
   doc.on('update', update => Y.applyUpdate(doc2, update))
@@ -347,9 +347,9 @@ export const testUndoUntilChangePerformed = tc => {
 
 /**
  * This issue has been reported in https://github.com/yjs/yjs/issues/317
- * @param {t.TestCase} tc
+ * @param {t.TestCase} _tc
  */
-export const testUndoNestedUndoIssue = tc => {
+export const testUndoNestedUndoIssue = _tc => {
   const doc = new Y.Doc({ gc: false })
   const design = doc.getMap()
   const undoManager = new Y.UndoManager(design, { captureTimeout: 0 })
@@ -403,9 +403,9 @@ export const testUndoNestedUndoIssue = tc => {
 /**
  * This issue has been reported in https://github.com/yjs/yjs/issues/355
  *
- * @param {t.TestCase} tc
+ * @param {t.TestCase} _tc
  */
-export const testConsecutiveRedoBug = tc => {
+export const testConsecutiveRedoBug = _tc => {
   const doc = new Y.Doc()
   const yRoot = doc.getMap()
   const undoMgr = new Y.UndoManager(yRoot)
@@ -454,9 +454,9 @@ export const testConsecutiveRedoBug = tc => {
 /**
  * This issue has been reported in https://github.com/yjs/yjs/issues/304
  *
- * @param {t.TestCase} tc
+ * @param {t.TestCase} _tc
  */
-export const testUndoXmlBug = tc => {
+export const testUndoXmlBug = _tc => {
   const origin = 'origin'
   const doc = new Y.Doc()
   const fragment = doc.getXmlFragment('t')
@@ -499,9 +499,9 @@ export const testUndoXmlBug = tc => {
 /**
  * This issue has been reported in https://github.com/yjs/yjs/issues/343
  *
- * @param {t.TestCase} tc
+ * @param {t.TestCase} _tc
  */
-export const testUndoBlockBug = tc => {
+export const testUndoBlockBug = _tc => {
   const doc = new Y.Doc({ gc: false })
   const design = doc.getMap()
 
@@ -559,9 +559,9 @@ export const testUndoBlockBug = tc => {
  * Undo text formatting delete should not corrupt peer state.
  *
  * @see https://github.com/yjs/yjs/issues/392
- * @param {t.TestCase} tc
+ * @param {t.TestCase} _tc
  */
-export const testUndoDeleteTextFormat = 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.')
@@ -597,9 +597,9 @@ export const testUndoDeleteTextFormat = tc => {
  * Undo text formatting delete should not corrupt peer state.
  *
  * @see https://github.com/yjs/yjs/issues/392
- * @param {t.TestCase} tc
+ * @param {t.TestCase} _tc
  */
-export const testBehaviorOfIgnoreremotemapchangesProperty = tc => {
+export const testBehaviorOfIgnoreremotemapchangesProperty = _tc => {
   const doc = new Y.Doc()
   const doc2 = new Y.Doc()
   doc.on('update', update => Y.applyUpdate(doc2, update, doc))
@@ -620,9 +620,9 @@ export const testBehaviorOfIgnoreremotemapchangesProperty = tc => {
  * Special deletion case.
  *
  * @see https://github.com/yjs/yjs/issues/447
- * @param {t.TestCase} tc
+ * @param {t.TestCase} _tc
  */
-export const testSpecialDeletionCase = tc => {
+export const testSpecialDeletionCase = _tc => {
   const origin = 'undoable'
   const doc = new Y.Doc()
   const fragment = doc.getXmlFragment()
@@ -644,3 +644,34 @@ export const testSpecialDeletionCase = tc => {
   undoManager.undo()
   t.compareStrings(fragment.toString(), '<test a="1" b="2"></test>')
 }
+
+/**
+ * Deleted entries in a map should be restored on undo.
+ *
+ * @see https://github.com/yjs/yjs/issues/500
+ * @param {t.TestCase} tc
+ */
+export const testUndoDeleteInMap = (tc) => {
+  const { map0 } = init(tc, { users: 3 })
+  const undoManager = new Y.UndoManager(map0, { captureTimeout: 0 })
+  map0.set('a', 'a')
+  map0.delete('a')
+  map0.set('a', 'b')
+  map0.delete('a')
+  map0.set('a', 'c')
+  map0.delete('a')
+  map0.set('a', 'd')
+  t.compare(map0.toJSON(), { a: 'd' })
+  undoManager.undo()
+  t.compare(map0.toJSON(), {})
+  undoManager.undo()
+  t.compare(map0.toJSON(), { a: 'c' })
+  undoManager.undo()
+  t.compare(map0.toJSON(), {})
+  undoManager.undo()
+  t.compare(map0.toJSON(), { a: 'b' })
+  undoManager.undo()
+  t.compare(map0.toJSON(), {})
+  undoManager.undo()
+  t.compare(map0.toJSON(), { a: 'a' })
+}

tests/updates.tests.js

@@ -4,6 +4,7 @@ import * as Y from '../src/index.js'
 import { readClientsStructRefs, readDeleteSet, UpdateDecoderV2, UpdateEncoderV2, writeDeleteSet } from '../src/internals.js'
 import * as encoding from 'lib0/encoding'
 import * as decoding from 'lib0/decoding'
+import * as object from 'lib0/object'
 
 /**
  * @typedef {Object} Enc
@@ -138,7 +139,6 @@ export const testKeyEncoding = tc => {
  */
 const checkUpdateCases = (ydoc, updates, enc, hasDeletes) => {
   const cases = []
-
   // Case 1: Simple case, simply merge everything
   cases.push(enc.mergeUpdates(updates))
 
@@ -304,3 +304,54 @@ export const testMergePendingUpdates = tc => {
   const yText5 = yDoc5.getText('textBlock')
   t.compareStrings(yText5.toString(), 'nenor')
 }
+
+/**
+ * @param {t.TestCase} tc
+ */
+export const testObfuscateUpdates = tc => {
+  const ydoc = new Y.Doc()
+  const ytext = ydoc.getText('text')
+  const ymap = ydoc.getMap('map')
+  const yarray = ydoc.getArray('array')
+  // test ytext
+  ytext.applyDelta([{ insert: 'text', attributes: { bold: true } }, { insert: { href: 'supersecreturl' } }])
+  // test ymap
+  ymap.set('key', 'secret1')
+  ymap.set('key', 'secret2')
+  // test yarray with subtype & subdoc
+  const subtype = new Y.XmlElement('secretnodename')
+  const subdoc = new Y.Doc({ guid: 'secret' })
+  subtype.setAttribute('attr', 'val')
+  yarray.insert(0, ['teststring', 42, subtype, subdoc])
+  // obfuscate the content and put it into a new document
+  const obfuscatedUpdate = Y.obfuscateUpdate(Y.encodeStateAsUpdate(ydoc))
+  const odoc = new Y.Doc()
+  Y.applyUpdate(odoc, obfuscatedUpdate)
+  const otext = odoc.getText('text')
+  const omap = odoc.getMap('map')
+  const oarray = odoc.getArray('array')
+  // test ytext
+  const delta = otext.toDelta()
+  t.assert(delta.length === 2)
+  t.assert(delta[0].insert !== 'text' && delta[0].insert.length === 4)
+  t.assert(object.length(delta[0].attributes) === 1)
+  t.assert(!object.hasProperty(delta[0].attributes, 'bold'))
+  t.assert(object.length(delta[1]) === 1)
+  t.assert(object.hasProperty(delta[1], 'insert'))
+  // test ymap
+  t.assert(omap.size === 1)
+  t.assert(!omap.has('key'))
+  // test yarray with subtype & subdoc
+  const result = oarray.toArray()
+  t.assert(result.length === 4)
+  t.assert(result[0] !== 'teststring')
+  t.assert(result[1] !== 42)
+  const osubtype = /** @type {Y.XmlElement} */ (result[2])
+  const osubdoc = result[3]
+  // test subtype
+  t.assert(osubtype.nodeName !== subtype.nodeName)
+  t.assert(object.length(osubtype.getAttributes()) === 1)
+  t.assert(osubtype.getAttribute('attr') === undefined)
+  // test subdoc
+  t.assert(osubdoc.guid !== subdoc.guid)
+}

tests/y-map.tests.js

@@ -337,6 +337,34 @@ export const testObserversUsingObservedeep = tc => {
   compare(users)
 }
 
+/**
+ * @param {t.TestCase} tc
+ */
+export const testPathsOfSiblingEvents = tc => {
+  const { users, map0 } = init(tc, { users: 2 })
+  /**
+   * @type {Array<Array<string|number>>}
+   */
+  const pathes = []
+  let calls = 0
+  const doc = users[0]
+  map0.set('map', new Y.Map())
+  map0.get('map').set('text1', new Y.Text('initial'))
+  map0.observeDeep(events => {
+    events.forEach(event => {
+      pathes.push(event.path)
+    })
+    calls++
+  })
+  doc.transact(() => {
+    map0.get('map').get('text1').insert(0, 'post-')
+    map0.get('map').set('text2', new Y.Text('new'))
+  })
+  t.assert(calls === 1)
+  t.compare(pathes, [['map'], ['map', 'text1']])
+  compare(users)
+}
+
 // TODO: Test events in Y.Map
 /**
  * @param {Object<string,any>} is

tests/y-xml.tests.js

@@ -3,6 +3,33 @@ import * as Y from '../src/index.js'
 
 import * as t from 'lib0/testing'
 
+export const testCustomTypings = () => {
+  const ydoc = new Y.Doc()
+  const ymap = ydoc.getMap()
+  /**
+   * @type {Y.XmlElement<{ num: number, str: string, [k:string]: object|number|string }>}
+   */
+  const yxml = ymap.set('yxml', new Y.XmlElement('test'))
+  /**
+   * @type {number|undefined}
+   */
+  const num = yxml.getAttribute('num')
+  /**
+   * @type {string|undefined}
+   */
+  const str = yxml.getAttribute('str')
+  /**
+   * @type {object|number|string|undefined}
+   */
+  const dtrn = yxml.getAttribute('dtrn')
+  const attrs = yxml.getAttributes()
+  /**
+   * @type {object|number|string|undefined}
+   */
+  const any = attrs.shouldBeAny
+  console.log({ num, str, dtrn, attrs, any })
+}
+
 /**
  * @param {t.TestCase} tc
  */
@@ -92,9 +119,9 @@ export const testTreewalker = tc => {
 }
 
 /**
- * @param {t.TestCase} tc
+ * @param {t.TestCase} _tc
  */
-export const testYtextAttributes = tc => {
+export const testYtextAttributes = _tc => {
   const ydoc = new Y.Doc()
   const ytext = /** @type {Y.XmlText} */ (ydoc.get('', Y.XmlText))
   ytext.observe(event => {
@@ -106,9 +133,9 @@ export const testYtextAttributes = tc => {
 }
 
 /**
- * @param {t.TestCase} tc
+ * @param {t.TestCase} _tc
  */
-export const testSiblings = tc => {
+export const testSiblings = _tc => {
   const ydoc = new Y.Doc()
   const yxml = ydoc.getXmlFragment()
   const first = new Y.XmlText()
@@ -122,9 +149,9 @@ export const testSiblings = tc => {
 }
 
 /**
- * @param {t.TestCase} tc
+ * @param {t.TestCase} _tc
  */
-export const testInsertafter = tc => {
+export const testInsertafter = _tc => {
   const ydoc = new Y.Doc()
   const yxml = ydoc.getXmlFragment()
   const first = new Y.XmlText()
@@ -152,9 +179,9 @@ export const testInsertafter = tc => {
 }
 
 /**
- * @param {t.TestCase} tc
+ * @param {t.TestCase} _tc
  */
-export const testClone = tc => {
+export const testClone = _tc => {
   const ydoc = new Y.Doc()
   const yxml = ydoc.getXmlFragment()
   const first = new Y.XmlText('text')
@@ -170,9 +197,9 @@ export const testClone = tc => {
 }
 
 /**
- * @param {t.TestCase} tc
+ * @param {t.TestCase} _tc
  */
-export const testFormattingBug = tc => {
+export const testFormattingBug = _tc => {
   const ydoc = new Y.Doc()
   const yxml = /** @type {Y.XmlText} */ (ydoc.get('', Y.XmlText))
   const delta = [

tsconfig.json

@@ -1,64 +1,21 @@
 {
   "compilerOptions": {
-    /* Basic Options */
-    "target": "es2018",
-    "lib": ["es2018", "dom"],                             /* Specify library files to be included in the compilation. */
-    "allowJs": true,                       /* Allow javascript files to be compiled. */
-    "checkJs": true,                       /* Report errors in .js files. */
-    // "jsx": "preserve",                     /* Specify JSX code generation: 'preserve', 'react-native', or 'react'. */
-    "declaration": true,                   /* Generates corresponding '.d.ts' file. */
-    // "declarationMap": true,                /* Generates a sourcemap for each corresponding '.d.ts' file. */
-    // "sourceMap": true,                     /* Generates corresponding '.map' file. */
-    // "outFile": "./dist/yjs.js",                       /* Concatenate and emit output to single file. */
-    "outDir": "./dist",                        /* Redirect output structure to the directory. */
-    "rootDir": "./",                       /* Specify the root directory of input files. Use to control the output directory structure with --outDir. */
-    // "composite": true,                     /* Enable project compilation */
-    // "removeComments": true,                /* Do not emit comments to output. */
-    // "noEmit": true,                        /* Do not emit outputs. */
-    // "importHelpers": true,                 /* Import emit helpers from 'tslib'. */
-    // "downlevelIteration": true,            /* Provide full support for iterables in 'for-of', spread, and destructuring when targeting 'ES5' or 'ES3'. */
-    // "isolatedModules": true,               /* Transpile each file as a separate module (similar to 'ts.transpileModule'). */
-
-    /* Strict Type-Checking Options */
-    "strict": true,                           /* Enable all strict type-checking options. */
-    "noImplicitAny": true,                 /* Raise error on expressions and declarations with an implied 'any' type. */
+    "target": "ES2021",
+    "lib": ["ES2021", "dom"],
+    "module": "node16",
+    "allowJs": true,
+    "checkJs": true,
+    "declaration": true,
+    "declarationMap": true,
+    "outDir": "./dist",
+    "baseUrl": "./",
     "emitDeclarationOnly": true,
-    // "strictNullChecks": true,              /* Enable strict null checks. */
-    // "strictFunctionTypes": true,           /* Enable strict checking of function types. */
-    // "strictPropertyInitialization": true,  /* Enable strict checking of property initialization in classes. */
-    // "noImplicitThis": true,                /* Raise error on 'this' expressions with an implied 'any' type. */
-    // "alwaysStrict": true,                  /* Parse in strict mode and emit "use strict" for each source file. */
-
-    /* Additional Checks */
-    // "noUnusedLocals": true,                /* Report errors on unused locals. */
-    // "noUnusedParameters": true,            /* Report errors on unused parameters. */
-    // "noImplicitReturns": true,             /* Report error when not all code paths in function return a value. */
-    // "noFallthroughCasesInSwitch": true,    /* Report errors for fallthrough cases in switch statement. */
-
-    /* Module Resolution Options */
-    "moduleResolution": "node",            /* Specify module resolution strategy: 'node' (Node.js) or 'classic' (TypeScript pre-1.6). */
-    "baseUrl": "./",                       /* Base directory to resolve non-absolute module names. */
+    "strict": true,
+    "noImplicitAny": true,
+    "moduleResolution": "nodenext",
     "paths": {
       "yjs": ["./src/index.js"]
-    },                           /* A series of entries which re-map imports to lookup locations relative to the 'baseUrl'. */
-    // "rootDirs": [],                        /* List of root folders whose combined content represents the structure of the project at runtime. */
-    // "typeRoots": [],                       /* List of folders to include type definitions from. */
-    // "types": [],                           /* Type declaration files to be included in compilation. */
-    // "allowSyntheticDefaultImports": true,  /* Allow default imports from modules with no default export. This does not affect code emit, just typechecking. */
-    "esModuleInterop": true,                   /* Enables emit interoperability between CommonJS and ES Modules via creation of namespace objects for all imports. Implies 'allowSyntheticDefaultImports'. */
-    // "preserveSymlinks": true,              /* Do not resolve the real path of symlinks. */
-
-    /* Source Map Options */
-    // "sourceRoot": "",                      /* Specify the location where debugger should locate TypeScript files instead of source locations. */
-    // "mapRoot": "",                         /* Specify the location where debugger should locate map files instead of generated locations. */
-    // "inlineSourceMap": true,               /* Emit a single file with source maps instead of having a separate file. */
-    // "inlineSources": true,                 /* Emit the source alongside the sourcemaps within a single file; requires '--inlineSourceMap' or '--sourceMap' to be set. */
-
-    /* Experimental Options */
-    // "experimentalDecorators": true,        /* Enables experimental support for ES7 decorators. */
-    // "emitDecoratorMetadata": true,         /* Enables experimental support for emitting type metadata for decorators. */
-    // "maxNodeModuleJsDepth": 0,
-    // "types": ["./src/utils/typedefs.js"]
+    }
   },
   "include": ["./src/**/*.js", "./tests/**/*.js"]
 }