13.4.3

fix a small typo (at it heart -> at its heart)

INTERNALS.md

@@ -12,7 +12,7 @@ which aren't described in the paper. The most notable is that items have an
 `originRight` as well as an `origin` property, which improves performance when
 many concurrent inserts happen after the same character.
 
-At it heart, Yjs is a list CRDT. Everything is squeezed into a list in order to
+At its heart, Yjs is a list CRDT. Everything is squeezed into a list in order to
 reuse the CRDT resolution algorithm:
 
 - Arrays are easy - they're lists of arbitrary items.

package-lock.json

@@ -1,6 +1,6 @@
 {
   "name": "yjs",
-  "version": "13.4.1",
+  "version": "13.4.3",
   "lockfileVersion": 1,
   "requires": true,
   "dependencies": {

package.json

@@ -1,6 +1,6 @@
 {
   "name": "yjs",
-  "version": "13.4.1",
+  "version": "13.4.3",
   "description": "Shared Editing Library",
   "main": "./dist/yjs.cjs",
   "module": "./dist/yjs.mjs",

src/structs/ContentString.js

@@ -51,6 +51,17 @@ export class ContentString {
   splice (offset) {
     const right = new ContentString(this.str.slice(offset))
     this.str = this.str.slice(0, offset)
+
+    // Prevent encoding invalid documents because of splitting of surrogate pairs: https://github.com/yjs/yjs/issues/248
+    const firstCharCode = this.str.charCodeAt(offset - 1)
+    if (firstCharCode >= 0xD800 && firstCharCode <= 0xDBFF) {
+      // Last character of the left split is the start of a surrogate utf16/ucs2 pair.
+      // We don't support splitting of surrogate pairs because this may lead to invalid documents.
+      // Replace the invalid character with a unicode replacement character (<28> / U+FFFD)
+      this.str = this.str.slice(0, offset - 1) + '<27>'
+      // replace right as well
+      right.str = '<27>' + right.str.slice(1)
+    }
     return right
   }
 

src/structs/Item.js

@@ -26,8 +26,6 @@ import {
 } from '../internals.js'
 
 import * as error from 'lib0/error.js'
-import * as maplib from 'lib0/map.js'
-import * as set from 'lib0/set.js'
 import * as binary from 'lib0/binary.js'
 
 /**
@@ -594,7 +592,7 @@ export class Item extends AbstractStruct {
       }
       this.markDeleted()
       addToDeleteSet(transaction.deleteSet, this.id.client, this.id.clock, this.length)
-      maplib.setIfUndefined(transaction.changed, parent, set.create).add(this.parentSub)
+      addChangedTypeToTransaction(transaction, parent, this.parentSub)
       this.content.delete(transaction)
     }
   }

src/utils/EventHandler.js

@@ -51,7 +51,12 @@ export const addEventHandlerListener = (eventHandler, f) =>
  * @function
  */
 export const removeEventHandlerListener = (eventHandler, f) => {
-  eventHandler.l = eventHandler.l.filter(g => f !== g)
+  const l = eventHandler.l
+  const len = l.length
+  eventHandler.l = l.filter(g => f !== g)
+  if (len === eventHandler.l.length) {
+    console.error('[yjs] Tried to remove event handler that doesn\'t exist.')
+  }
 }
 
 /**

src/utils/Transaction.js

@@ -284,6 +284,9 @@ const cleanupTransactions = (transactionCleanups, i) => {
                 .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)

tests/y-array.tests.js

@@ -204,6 +204,34 @@ export const testInsertAndDeleteEventsForTypes = tc => {
   compare(users)
 }
 
+/**
+ * This issue has been reported in https://discuss.yjs.dev/t/order-in-which-events-yielded-by-observedeep-should-be-applied/261/2
+ *
+ * Deep observers generate multiple events. When an array added at item at, say, position 0,
+ * and item 1 changed then the array-add event should fire first so that the change event
+ * path is correct. A array binding might lead to an inconsistent state otherwise.
+ *
+ * @param {t.TestCase} tc
+ */
+export const testObserveDeepEventOrder = tc => {
+  const { array0, users } = init(tc, { users: 2 })
+  /**
+   * @type {Array<any>}
+   */
+  let events = []
+  array0.observeDeep(e => {
+    events = e
+  })
+  array0.insert(0, [new Y.Map()])
+  users[0].transact(() => {
+    array0.get(0).set('a', 'a')
+    array0.insert(0, [0])
+  })
+  for (let i = 1; i < events.length; i++) {
+    t.assert(events[i - 1].path.length <= events[i].path.length, 'path size increases, fire top-level events first')
+  }
+}
+
 /**
  * @param {t.TestCase} tc
  */

tests/y-text.tests.js

@@ -249,6 +249,8 @@ export const testAppendChars = tc => {
   t.assert(text0.length === N)
 }
 
+const largeDocumentSize = 100000
+
 const id = Y.createID(0, 0)
 const c = new Y.ContentString('a')
 
@@ -256,7 +258,7 @@ const c = new Y.ContentString('a')
  * @param {t.TestCase} tc
  */
 export const testBestCase = tc => {
-  const N = 2000000
+  const N = largeDocumentSize
   const items = new Array(N)
   t.measureTime('time to create two million items in the best case', () => {
     const parent = /** @type {any} */ ({})
@@ -293,7 +295,7 @@ const tryGc = () => {
  * @param {t.TestCase} tc
  */
 export const testLargeFragmentedDocument = tc => {
-  const itemsToInsert = 1000000
+  const itemsToInsert = largeDocumentSize
   let update = /** @type {any} */ (null)
   ;(() => {
     const doc1 = new Y.Doc()
@@ -321,6 +323,40 @@ export const testLargeFragmentedDocument = tc => {
   })()
 }
 
+/**
+ * Splitting surrogates can lead to invalid encoded documents.
+ *
+ * https://github.com/yjs/yjs/issues/248
+ *
+ * @param {t.TestCase} tc
+ */
+export const testSplitSurrogateCharacter = tc => {
+  {
+    const { users, text0 } = init(tc, { users: 2 })
+    users[1].disconnect() // disconnecting forces the user to encode the split surrogate
+    text0.insert(0, '👾') // insert surrogate character
+    // split surrogate, which should not lead to an encoding error
+    text0.insert(1, 'hi!')
+    compare(users)
+  }
+  {
+    const { users, text0 } = init(tc, { users: 2 })
+    users[1].disconnect() // disconnecting forces the user to encode the split surrogate
+    text0.insert(0, '👾👾') // insert surrogate character
+    // partially delete surrogate
+    text0.delete(1, 2)
+    compare(users)
+  }
+  {
+    const { users, text0 } = init(tc, { users: 2 })
+    users[1].disconnect() // disconnecting forces the user to encode the split surrogate
+    text0.insert(0, '👾👾') // insert surrogate character
+    // formatting will also split surrogates
+    text0.format(1, 2, { bold: true })
+    compare(users)
+  }
+}
+
 // RANDOM TESTS
 
 let charCounter = 0