fixed undo/redo issues and implemented ability to manually flush the UndoManager

src/Bindings/DomBinding/DomBinding.js

@@ -1,8 +1,9 @@
-/* global MutationObserver */
+/* global MutationObserver, getSelection */
 
+import { fromRelativePosition } from '../../Util/relativePosition.js'
 import Binding from '../Binding.js'
 import { createAssociation, removeAssociation } from './util.js'
-import { beforeTransactionSelectionFixer, afterTransactionSelectionFixer } from './selection.js'
+import { beforeTransactionSelectionFixer, afterTransactionSelectionFixer, getCurrentRelativeSelection } from './selection.js'
 import { defaultFilter, applyFilterOnType } from './filter.js'
 import typeObserver from './typeObserver.js'
 import domObserver from './domObserver.js'
@@ -67,16 +68,25 @@ export default class DomBinding extends Binding {
       characterData: true,
       subtree: true
     })
+    this._currentSel = null
+    document.addEventListener('selectionchange', () => {
+      this._currentSel = getCurrentRelativeSelection(this)
+    })
     const y = type._y
+    this.y = y
     // Force flush dom changes before Type changes are applied (they might
     // modify the dom)
     this._beforeTransactionHandler = (y, transaction, remote) => {
       this._domObserver(this._mutationObserver.takeRecords())
-      beforeTransactionSelectionFixer(y, this, transaction, remote)
+      this._mutualExclude(() => {
+        beforeTransactionSelectionFixer(this, remote)
+      })
     }
     y.on('beforeTransaction', this._beforeTransactionHandler)
     this._afterTransactionHandler = (y, transaction, remote) => {
-      afterTransactionSelectionFixer(y, this, transaction, remote)
+      this._mutualExclude(() => {
+        afterTransactionSelectionFixer(this, remote)
+      })
       // remove associations
       // TODO: this could be done more efficiently
       // e.g. Always delete using the following approach, or removeAssociation
@@ -115,6 +125,67 @@ export default class DomBinding extends Binding {
     // TODO: apply filter to all elements
   }
 
+  _getUndoStackInfo () {
+    return this.getSelection()
+  }
+
+  _restoreUndoStackInfo (info) {
+    this.restoreSelection(info)
+  }
+
+  getSelection () {
+    return this._currentSel
+  }
+
+  restoreSelection (selection) {
+    if (selection !== null) {
+      const { to, from } = selection
+      let shouldUpdate = false
+      /**
+       * There is little information on the difference between anchor/focus and base/extent.
+       * MDN doesn't even mention base/extent anymore.. though you still have to call
+       * setBaseAndExtent to change the selection..
+       * I can observe that base/extend refer to notes higher up in the xml hierachy.
+       * Espesially for undo/redo this is preferred. If this becomes a problem in the future,
+       * we should probably go back to anchor/focus.
+       */
+      const browserSelection = getSelection()
+      let { baseNode, baseOffset, extentNode, extentOffset } = browserSelection
+      if (from !== null) {
+        let sel = fromRelativePosition(this.y, from)
+        if (sel !== null) {
+          let node = this.typeToDom.get(sel.type)
+          let offset = sel.offset
+          if (node !== baseNode || offset !== baseOffset) {
+            baseNode = node
+            baseOffset = offset
+            shouldUpdate = true
+          }
+        }
+      }
+      if (to !== null) {
+        let sel = fromRelativePosition(this.y, to)
+        if (sel !== null) {
+          let node = this.typeToDom.get(sel.type)
+          let offset = sel.offset
+          if (node !== extentNode || offset !== extentOffset) {
+            extentNode = node
+            extentOffset = offset
+            shouldUpdate = true
+          }
+        }
+      }
+      if (shouldUpdate) {
+        browserSelection.setBaseAndExtent(
+          baseNode,
+          baseOffset,
+          extentNode,
+          extentOffset
+        )
+      }
+    }
+  }
+
   /**
    * Remove all properties that are handled by this class.
    */
@@ -130,7 +201,6 @@ export default class DomBinding extends Binding {
     super.destroy()
   }
 }
-
 /**
  * A filter defines which elements and attributes to share.
  * Return null if the node should be filtered. Otherwise return the Map of

src/Bindings/DomBinding/selection.js

@@ -1,84 +1,35 @@
 /* globals getSelection */
 
-import { getRelativePosition, fromRelativePosition } from '../../Util/relativePosition.js'
+import { getRelativePosition } from '../../Util/relativePosition.js'
 
-let browserSelection = null
 let relativeSelection = null
 
-/**
+function _getCurrentRelativeSelection (domBinding) {
- * @private
+  const { baseNode, baseOffset, extentNode, extentOffset } = getSelection()
- */
+  const baseNodeType = domBinding.domToType.get(baseNode)
-export let beforeTransactionSelectionFixer
+  const extentNodeType = domBinding.domToType.get(extentNode)
-if (typeof getSelection !== 'undefined') {
+  if (baseNodeType !== undefined && extentNodeType !== undefined) {
-  beforeTransactionSelectionFixer = function _beforeTransactionSelectionFixer (y, domBinding, transaction, remote) {
+    return {
-    if (!remote) {
+      from: getRelativePosition(baseNodeType, baseOffset),
-      return
+      to: getRelativePosition(extentNodeType, extentOffset)
-    }
-    relativeSelection = { from: null, to: null, fromY: null, toY: null }
-    browserSelection = getSelection()
-    const anchorNode = browserSelection.anchorNode
-    const anchorNodeType = domBinding.domToType.get(anchorNode)
-    if (anchorNode !== null && anchorNodeType !== undefined) {
-      relativeSelection.from = getRelativePosition(anchorNodeType, browserSelection.anchorOffset)
-      relativeSelection.fromY = anchorNodeType._y
-    }
-    const focusNode = browserSelection.focusNode
-    const focusNodeType = domBinding.domToType.get(focusNode)
-    if (focusNode !== null && focusNodeType !== undefined) {
-      relativeSelection.to = getRelativePosition(focusNodeType, browserSelection.focusOffset)
-      relativeSelection.toY = focusNodeType._y
     }
   }
-} else {
+  return null
-  beforeTransactionSelectionFixer = function _fakeBeforeTransactionSelectionFixer () {}
+}
+
+export const getCurrentRelativeSelection = typeof getSelection !== 'undefined' ? _getCurrentRelativeSelection : () => null
+
+export function beforeTransactionSelectionFixer (domBinding, remote) {
+  if (remote) {
+    relativeSelection = getCurrentRelativeSelection(domBinding)
+  }
 }
 
 /**
  * @private
  */
-export function afterTransactionSelectionFixer (y, domBinding, transaction, remote) {
+export function afterTransactionSelectionFixer (domBinding, remote) {
-  if (relativeSelection === null || !remote) {
+  if (relativeSelection !== null && remote) {
-    return
+    domBinding.restoreSelection(relativeSelection)
-  }
-  const to = relativeSelection.to
-  const from = relativeSelection.from
-  const fromY = relativeSelection.fromY
-  const toY = relativeSelection.toY
-  let shouldUpdate = false
-  let anchorNode = browserSelection.anchorNode
-  let anchorOffset = browserSelection.anchorOffset
-  let focusNode = browserSelection.focusNode
-  let focusOffset = browserSelection.focusOffset
-  if (from !== null) {
-    let sel = fromRelativePosition(fromY, from)
-    if (sel !== null) {
-      let node = domBinding.typeToDom.get(sel.type)
-      let offset = sel.offset
-      if (node !== anchorNode || offset !== anchorOffset) {
-        anchorNode = node
-        anchorOffset = offset
-        shouldUpdate = true
-      }
-    }
-  }
-  if (to !== null) {
-    let sel = fromRelativePosition(toY, to)
-    if (sel !== null) {
-      let node = domBinding.typeToDom.get(sel.type)
-      let offset = sel.offset
-      if (node !== focusNode || offset !== focusOffset) {
-        focusNode = node
-        focusOffset = offset
-        shouldUpdate = true
-      }
-    }
-  }
-  if (shouldUpdate) {
-    browserSelection.setBaseAndExtent(
-      anchorNode,
-      anchorOffset,
-      focusNode,
-      focusOffset
-    )
   }
 }

src/Struct/Item.js

@@ -120,7 +120,7 @@ export default class Item {
    *
    * @private
    */
-  _redo (y) {
+  _redo (y, redoitems) {
     if (this._redone !== null) {
       return this._redone
     }
@@ -130,7 +130,10 @@ export default class Item {
     let parent = this._parent
     // make sure that parent is redone
     if (parent._deleted === true && parent._redone === null) {
-      parent._redo(y)
+      // try to undo parent if it will be undone anyway
+      if (!redoitems.has(parent) || !parent._redo(y, redoitems)) {
+        return false
+      }
     }
     if (parent._redone !== null) {
       parent = parent._redone
@@ -157,7 +160,7 @@ export default class Item {
     struct._parentSub = this._parentSub
     struct._integrate(y)
     this._redone = struct
-    return struct
+    return true
   }
 
   /**

src/Util/UndoManager.js

@@ -2,7 +2,7 @@ import ID from './ID/ID.js'
 import isParentOf from './isParentOf.js'
 
 class ReverseOperation {
-  constructor (y, transaction) {
+  constructor (y, transaction, bindingInfos) {
     this.created = new Date()
     const beforeState = transaction.beforeState
     if (beforeState.has(y.userID)) {
@@ -12,15 +12,26 @@ class ReverseOperation {
       this.toState = null
       this.fromState = null
     }
-    this.deletedStructs = transaction.deletedStructs
+    this.deletedStructs = new Set()
+    transaction.deletedStructs.forEach(struct => {
+      this.deletedStructs.add({
+        from: struct._id,
+        len: struct._length
+      })
+    })
+    /**
+     * Maps from binding to binding information (e.g. cursor information)
+     */
+    this.bindingInfos = bindingInfos
   }
 }
 
 function applyReverseOperation (y, scope, reverseBuffer) {
   let performedUndo = false
+  let undoOp
   y.transact(() => {
     while (!performedUndo && reverseBuffer.length > 0) {
-      let undoOp = reverseBuffer.pop()
+      undoOp = reverseBuffer.pop()
       // make sure that it is possible to iterate {from}-{to}
       if (undoOp.fromState !== null) {
         y.os.getItemCleanStart(undoOp.fromState)
@@ -35,7 +46,13 @@ function applyReverseOperation (y, scope, reverseBuffer) {
           }
         })
       }
-      for (let op of undoOp.deletedStructs) {
+      const redoitems = new Set()
+      for (let del of undoOp.deletedStructs) {
+        const fromState = del.from
+        const toState = new ID(fromState.user, fromState.clock + del.len - 1)
+        y.os.getItemCleanStart(fromState)
+        y.os.getItemCleanEnd(toState)
+        y.os.iterate(fromState, toState, op => {
           if (
             isParentOf(scope, op) &&
             op._parent !== y &&
@@ -46,12 +63,22 @@ function applyReverseOperation (y, scope, reverseBuffer) {
               op._id.clock > undoOp.toState.clock
             )
           ) {
-          performedUndo = true
+            redoitems.add(op)
-          op._redo(y)
-        }
-      }
           }
         })
+      }
+      redoitems.forEach(op => {
+        const opUndone = op._redo(y, redoitems)
+        performedUndo = performedUndo || opUndone
+      })
+    }
+  })
+  if (performedUndo) {
+    // should be performed after the undo transaction
+    undoOp.bindingInfos.forEach((info, binding) => {
+      binding._restoreUndoStackInfo(info)
+    })
+  }
   return performedUndo
 }
 
@@ -66,6 +93,7 @@ export default class UndoManager {
    */
   constructor (scope, options = {}) {
     this.options = options
+    this._bindings = new Set(options.bindings)
     options.captureTimeout = options.captureTimeout == null ? 500 : options.captureTimeout
     this._undoBuffer = []
     this._redoBuffer = []
@@ -76,16 +104,28 @@ export default class UndoManager {
     const y = scope._y
     this.y = y
     y._hasUndoManager = true
+    let bindingInfos
+    y.on('beforeTransaction', (y, transaction, remote) => {
+      if (!remote) {
+        // Store binding information before transaction is executed
+        // By restoring the binding information, we can make sure that the state
+        // before the transaction can be recovered
+        bindingInfos = new Map()
+        this._bindings.forEach(binding => {
+          bindingInfos.set(binding, binding._getUndoStackInfo())
+        })
+      }
+    })
     y.on('afterTransaction', (y, transaction, remote) => {
       if (!remote && transaction.changedParentTypes.has(scope)) {
-        let reverseOperation = new ReverseOperation(y, transaction)
+        let reverseOperation = new ReverseOperation(y, transaction, bindingInfos)
         if (!this._undoing) {
           let lastUndoOp = this._undoBuffer.length > 0 ? this._undoBuffer[this._undoBuffer.length - 1] : null
           if (
             this._redoing === false &&
             this._lastTransactionWasUndo === false &&
             lastUndoOp !== null &&
-            reverseOperation.created - lastUndoOp.created <= options.captureTimeout
+            (options.captureTimeout < 0 || reverseOperation.created - lastUndoOp.created <= options.captureTimeout)
           ) {
             lastUndoOp.created = reverseOperation.created
             if (reverseOperation.toState !== null) {
@@ -110,6 +150,13 @@ export default class UndoManager {
     })
   }
 
+  /**
+   * Enforce that the next change is created as a separate item in the undo stack
+   */
+  flushChanges () {
+    this._lastTransactionWasUndo = true
+  }
+
   /**
    * Undo the last locally created change.
    */

src/Util/relativePosition.js

@@ -76,7 +76,10 @@ export function fromRelativePosition (y, rpos) {
     } else {
       id = new RootID(rpos[3], rpos[4])
     }
-    const type = y.os.get(id)
+    let type = y.os.get(id)
+    while (type._redone !== null) {
+      type = type._redone
+    }
     if (type === null || type.constructor === GC) {
       return null
     }
@@ -87,12 +90,16 @@ export function fromRelativePosition (y, rpos) {
   } else {
     let offset = 0
     let struct = y.os.findNodeWithUpperBound(new ID(rpos[0], rpos[1])).val
+    const diff = rpos[1] - struct._id.clock
+    while (struct._redone !== null) {
+      struct = struct._redone
+    }
     const parent = struct._parent
     if (struct.constructor === GC || parent._deleted) {
       return null
     }
     if (!struct._deleted) {
-      offset = rpos[1] - struct._id.clock
+      offset = diff
     }
     struct = struct._left
     while (struct !== null) {