Ticket #3372: 3372_7.patch

_source/plugins/undo/plugin.js

@@ -82 +82 @@
                                                                 {
                                                                         // Do not capture CTRL hotkeys.
                                                                         if ( !event.data.$.ctrlKey && !event.data.$.metaKey )
-                                                                                undoManager.type();
+                                                                                undoManager.type( event );
                                                                 });
 
                                                         // Being this the first call, let's get an undo snapshot.
@@ -167 +167 @@
         function UndoManager( editor )
         {
                 this.typesCount = 0;
+                this.modifiersCount = 0;
 
                 this.editor = editor;
 
@@ -182 +183 @@
                 this.index = -1;
 
                 this.limit = editor.config.undoStackSize;
+
+                /**
+                 * Remember last pressed key.
+                 */
+                this.lastKeystroke = 0;
         }
 
         UndoManager.prototype =
         {
-                type : function()
+                /**
+                 * Process undo system regard keystrikes.
+                 * @param {CKEDITOR.dom.event} event
+                 */
+                type : function( event )
                 {
-                        if ( !this.typing )
+                        var keystroke = event && event.data.getKeystroke(),
+
+                                // Backspace, Delete
+                                modifierCodes = { 8:1, 46:1 },
+                                // Keystrokes which will modify the contents.
+                                isModifier = keystroke in modifierCodes,
+                                wasModifier = this.lastKeystroke in modifierCodes,
+                                lastWasSameModifier = isModifier && keystroke == this.lastKeystroke,
+
+                                // Arrows: L, T, R, B
+                                resetTypingCodes = { 37:1, 38:1, 39:1, 40:1 },
+                                // Keystrokes which navigation through contents.
+                                isReset = keystroke in resetTypingCodes,
+                                wasReset = this.lastKeystroke in resetTypingCodes,
+
+                                // Keystrokes which just introduce new contents.
+                                isContent = ( !isModifier && !isReset ),
+
+                                // Create undo snap for every different modifier key.
+                                modifierSnapshot = ( isModifier && !lastWasSameModifier ),
+                                // Create undo snap on the following cases:
+                                // 1. Just start to type.
+                                // 2. Typing some content after a modifier.
+                                // 3. Typing some content after make a visible selection.
+                                startedTyping = !this.typing
+                                        || ( isContent && ( wasModifier || wasReset ) );
+
+                        if ( startedTyping || modifierSnapshot )
                         {
                                 var beforeTypeImage = new Image( this.editor );
 
@@ -204 +241 @@
 
                                                 if ( beforeTypeImage.contents != currentSnapshot )
                                                 {
-                                                        if ( !this.save( false, beforeTypeImage ) )
-                                                        {
+                                                        // This's a special save, with specified snapshot
+                                                        // and without auto 'fireChange'.
+                                                        if ( !this.save( false, beforeTypeImage, false ) )
                                                                 // Drop future snapshots.
                                                                 this.snapshots.splice( this.index + 1, this.snapshots.length - this.index - 1 );
-                                                        }
 
                                                         this.hasUndo = true;
                                                         this.hasRedo = false;
 
                                                         this.typesCount = 1;
-                                                        this.typing = true;
+                                                        this.modifiersCount = 1;
 
                                                         this.onChange();
                                                 }
                                         },
-                                        0, this );
-
-                                return;
+                                        0, this
+                                );
                         }
 
-                        this.typesCount++;
+                        this.lastKeystroke = keystroke;
+                        // Create undo snap after typed too much (over 25 times).
+                        if ( isModifier )
+                        {
+                                this.typesCount = 0;
+                                this.modifiersCount++;
+
+                                if ( this.modifiersCount > 25 )
+                                {
+                                        this.save();
+                                        this.modifiersCount = 1;
+                                }
+                        }
+                        else if ( !isReset )
+                        {
+                                this.modifiersCount = 0;
+                                this.typesCount++;
 
-                        if ( this.typesCount > 25 )
-                        {
-                                this.save();
-                                this.typesCount = 1;
-                        }
+                                if ( this.typesCount > 25 )
+                                {
+                                        this.save();
+                                        this.typesCount = 1;
+                                }
+                        }
 
                         this.typing = true;
                 },
 
+                /**
+                 * Reset all states about typing.
+                 * @see  UndoManager.type
+                 */
+                resetType : function()
+                {
+                        this.typing = false;
+                        delete this.lastKeystroke;
+                        this.typesCount = 0;
+                        this.modifiersCount = 0;
+                },
                 fireChange : function()
                 {
                         this.hasUndo = !!this.getNextImage( true );
                         this.hasRedo = !!this.getNextImage( false );
-
-                        this.typing = false;
-                        this.typesCount = 0;
-
+                        // Reset typing
+                        this.resetType();
                         this.onChange();
                 },
 
                 /**
                  * Save a snapshot of document image for later retrieve.
                  */
-                save : function( onContentOnly, image )
+                save : function( onContentOnly, image, autoFireChange )
                 {
                         var snapshots = this.snapshots;
 
@@ -273 +335 @@
 
                         this.currentImage = image;
 
-                        this.fireChange();
-
+                        if ( autoFireChange !== false )
+                                this.fireChange();
                         return true;
                 },