Merge remote-tracking branch 'origin/master' into macgtk

Conflicts:
	extras/GtkSourceViewEditor/MonoDevelop.SourceEditor.addin.xml
	main/src/addins/MonoDevelop.AssemblyBrowser/MonoDevelop.AssemblyBrowser/AssemblyBrowserWidget.cs
	main/src/core/Mono.Texteditor/Mono.TextEditor/GtkWorkarounds.cs

5 files changed, 185 insertions, 187 deletions

diff --git a/main/src/addins/MonoDevelop.SourceEditor2/MonoDevelop.SourceEditor.addin.xml b/main/src/addins/MonoDevelop.SourceEditor2/MonoDevelop.SourceEditor.addin.xml
index e06dec5121..62dbe8c026 100644
--- a/main/src/addins/MonoDevelop.SourceEditor2/MonoDevelop.SourceEditor.addin.xml
+++ b/main/src/addins/MonoDevelop.SourceEditor2/MonoDevelop.SourceEditor.addin.xml
@@ -7,16 +7,16 @@
        description = "Provides a text editor for the MonoDevelop based on Mono.TextEditor"
        category    = "MonoDevelop Core"
        flags       = "Hidden"
-       version     = "2.8.1">
+       version     = "2.8.2">
 	
 	<Runtime>
 		<Import assembly="MonoDevelop.SourceEditor2.dll"/>
 	</Runtime>
 	
 	<Dependencies>
-	    <Addin id="Core" version="2.8.1"/>
-		<Addin id="Ide" version="2.8.1"/>
-		<Addin id="Debugger" version="2.8.1"/>
+	    <Addin id="Core" version="2.8.2"/>
+		<Addin id="Ide" version="2.8.2"/>
+		<Addin id="Debugger" version="2.8.2"/>
 	</Dependencies>
 
 	<!-- Extension points -->
diff --git a/main/src/addins/MonoDevelop.SourceEditor2/MonoDevelop.SourceEditor/ExtensibleTextEditor.cs b/main/src/addins/MonoDevelop.SourceEditor2/MonoDevelop.SourceEditor/ExtensibleTextEditor.cs
index e9890837dd..19a72e118c 100644
--- a/main/src/addins/MonoDevelop.SourceEditor2/MonoDevelop.SourceEditor/ExtensibleTextEditor.cs
+++ b/main/src/addins/MonoDevelop.SourceEditor2/MonoDevelop.SourceEditor/ExtensibleTextEditor.cs
@@ -353,6 +353,7 @@ namespace MonoDevelop.SourceEditor
 					skipChar = null;
 			}
 			char insertionChar = '\0';
+			IDisposable undoGroup = null;
 			if (skipChar == null && Options.AutoInsertMatchingBracket && braceIndex >= 0) {
 				if (!inStringOrComment) {
 					char closingBrace = closingBrackets [braceIndex];
@@ -369,7 +370,7 @@ namespace MonoDevelop.SourceEditor
 
 					if (count >= 0) {
 						startedAtomicOperation = true;
-						Document.BeginAtomicUndo ();
+						undoGroup = Document.OpenUndoGroup ();
 						GetTextEditorData ().EnsureCaretIsNotVirtual ();
 						
 						int offset = Caret.Offset;
@@ -382,7 +383,7 @@ namespace MonoDevelop.SourceEditor
 					char charBefore = Document.GetCharAt (Caret.Offset - 1);
 					if (!inString && !inComment && !inChar && ch == '"' && charBefore != '\\') {
 						startedAtomicOperation = true;
-						Document.BeginAtomicUndo ();
+						undoGroup = Document.OpenUndoGroup ();
 						GetTextEditorData ().EnsureCaretIsNotVirtual ();
 						insertionChar = '"';
 						int offset = Caret.Offset;
@@ -409,8 +410,8 @@ namespace MonoDevelop.SourceEditor
 						HitReturn ();
 				}
 			}
-			if (startedAtomicOperation)
-				Document.EndAtomicUndo ();
+			if (undoGroup != null)
+				undoGroup.Dispose ();
 			return templateInserted || result;
 		}
 		
@@ -615,17 +616,17 @@ namespace MonoDevelop.SourceEditor
 			return false;
 		}
 		
-		void HandleTextPaste (int insertionOffset, string text)
+		void HandleTextPaste (int insertionOffset, string text, int insertedChars)
 		{
 			if (PropertyService.Get ("OnTheFlyFormatting", false)) {
 				var prettyPrinter = CodeFormatterService.GetFormatter (Document.MimeType);
 				if (prettyPrinter != null && ProjectDom != null && text != null) {
 					try {
 						var policies = ProjectDom != null && ProjectDom.Project != null ? ProjectDom.Project.Policies : null;
-						string newText = prettyPrinter.FormatText (policies, Document.Text, insertionOffset, insertionOffset + text.Length);
+						string newText = prettyPrinter.FormatText (policies, Document.Text, insertionOffset, insertionOffset + insertedChars);
 						if (!string.IsNullOrEmpty (newText)) {
-							Replace (insertionOffset, text.Length, newText);
-							Caret.Offset = insertionOffset + newText.Length;
+							int replaceResult = Replace (insertionOffset, insertedChars, newText);
+							Caret.Offset = insertionOffset + replaceResult;
 						}
 					} catch (Exception e) {
 						LoggingService.LogError ("Error formatting pasted text", e);
@@ -636,39 +637,39 @@ namespace MonoDevelop.SourceEditor
 		
 		internal void InsertTemplate (CodeTemplate template, MonoDevelop.Ide.Gui.Document document)
 		{
-			Document.BeginAtomicUndo ();
-			var result = template.InsertTemplateContents (document);
-			var tle = new TextLinkEditMode (this, result.InsertPosition, result.TextLinks);
-			
-			if (PropertyService.Get ("OnTheFlyFormatting", false)) {
-				var prettyPrinter = CodeFormatterService.GetFormatter (Document.MimeType);
-				if (prettyPrinter != null) {
-					int endOffset = result.InsertPosition + result.Code.Length;
-					string oldText = Document.GetTextAt (result.InsertPosition, result.Code.Length);
-					var policies = document.Project != null ? document.Project.Policies : null;
-					string text = prettyPrinter.FormatText (policies, Document.Text, result.InsertPosition, endOffset);
-					
-					if (text != null)
-						Replace (result.InsertPosition, result.Code.Length, text);
-					else
-						//if formatting failed, just use the unformatted text
-						text = oldText;
-					
-					Caret.Offset = result.InsertPosition + TranslateOffset (oldText, text, Caret.Offset - result.InsertPosition);
-					foreach (TextLink textLink in tle.Links) {
-						foreach (ISegment segment in textLink.Links) {
-							segment.Offset = TranslateOffset (oldText, text, segment.Offset);
+			using (var undo = Document.OpenUndoGroup ()) {
+				var result = template.InsertTemplateContents (document);
+				var tle = new TextLinkEditMode (this, result.InsertPosition, result.TextLinks);
+				
+				if (PropertyService.Get ("OnTheFlyFormatting", false)) {
+					var prettyPrinter = CodeFormatterService.GetFormatter (Document.MimeType);
+					if (prettyPrinter != null) {
+						int endOffset = result.InsertPosition + result.Code.Length;
+						string oldText = Document.GetTextAt (result.InsertPosition, result.Code.Length);
+						var policies = document.Project != null ? document.Project.Policies : null;
+						string text = prettyPrinter.FormatText (policies, Document.Text, result.InsertPosition, endOffset);
+						
+						if (text != null)
+							Replace (result.InsertPosition, result.Code.Length, text);
+						else
+							//if formatting failed, just use the unformatted text
+							text = oldText;
+						
+						Caret.Offset = result.InsertPosition + TranslateOffset (oldText, text, Caret.Offset - result.InsertPosition);
+						foreach (TextLink textLink in tle.Links) {
+							foreach (ISegment segment in textLink.Links) {
+								segment.Offset = TranslateOffset (oldText, text, segment.Offset);
+							}
 						}
 					}
 				}
+				
+				if (tle.ShouldStartTextLinkMode) {
+					tle.OldMode = CurrentMode;
+					tle.StartMode ();
+					CurrentMode = tle;
+				}
 			}
-			
-			if (tle.ShouldStartTextLinkMode) {
-				tle.OldMode = CurrentMode;
-				tle.StartMode ();
-				CurrentMode = tle;
-			}
-			Document.EndAtomicUndo ();
 		}
 		
 		static int TranslateOffset (string baseInput, string formattedInput, int offset)
@@ -1035,11 +1036,8 @@ namespace MonoDevelop.SourceEditor
 		[CommandHandler (MonoDevelop.Ide.Commands.EditCommands.JoinWithNextLine)]
 		internal void JoinLines ()
 		{
-			try {
-				Document.BeginAtomicUndo ();
+			using (var undo = Document.OpenUndoGroup ()) {
 				RunAction (Mono.TextEditor.Vi.ViActions.Join);
-			} finally {
-				Document.EndAtomicUndo ();
 			}
 		}
 		
diff --git a/main/src/addins/MonoDevelop.SourceEditor2/MonoDevelop.SourceEditor/MessageBubbleHighlightPopupWindow.cs b/main/src/addins/MonoDevelop.SourceEditor2/MonoDevelop.SourceEditor/MessageBubbleHighlightPopupWindow.cs
index 8f3534417a..48bb35ccd6 100644
--- a/main/src/addins/MonoDevelop.SourceEditor2/MonoDevelop.SourceEditor/MessageBubbleHighlightPopupWindow.cs
+++ b/main/src/addins/MonoDevelop.SourceEditor2/MonoDevelop.SourceEditor/MessageBubbleHighlightPopupWindow.cs
@@ -103,6 +103,8 @@ namespace MonoDevelop.SourceEditor
 				cr.Stroke ();
 				int errorCounterWidth = 0;
 				
+				marker.EnsureLayoutCreated (base.Editor);
+				
 				if (marker.Errors.Count > 1) {
 					double rY = y + Editor.LineHeight / 6;
 					int ew, eh;
@@ -127,7 +129,6 @@ namespace MonoDevelop.SourceEditor
 				}
 				
 				cr.Color = new Cairo.Color (0, 0, 0);
-				marker.EnsureLayoutCreated (base.Editor);
 				
 				int layoutWidth, layoutHeight;
 				marker.Layouts [0].Layout.GetPixelSize (out layoutWidth, out layoutHeight);
diff --git a/main/src/addins/MonoDevelop.SourceEditor2/MonoDevelop.SourceEditor/SourceEditorView.cs b/main/src/addins/MonoDevelop.SourceEditor2/MonoDevelop.SourceEditor/SourceEditorView.cs
index 03aeb05ac3..1f90b6915d 100644
--- a/main/src/addins/MonoDevelop.SourceEditor2/MonoDevelop.SourceEditor/SourceEditorView.cs
+++ b/main/src/addins/MonoDevelop.SourceEditor2/MonoDevelop.SourceEditor/SourceEditorView.cs
@@ -257,20 +257,20 @@ namespace MonoDevelop.SourceEditor
 
 		void HandleTaskServiceJumpedToTask (object sender, TaskEventArgs e)
 		{
-			Task task = e.Tasks.FirstOrDefault ();
+			var task = e.Tasks != null ? e.Tasks.FirstOrDefault () : null;
 			var doc = Document;
 			if (task == null || doc == null || task.FileName != doc.FileName || this.TextEditor == null)
 				return;
-			LineSegment lineSegment = doc.GetLine (task.Line);
+			var lineSegment = doc.GetLine (task.Line);
 			if (lineSegment == null)
 				return;
-			MessageBubbleTextMarker marker = (MessageBubbleTextMarker)lineSegment.Markers.FirstOrDefault (m => m is MessageBubbleTextMarker);
+			var marker = (MessageBubbleTextMarker)lineSegment.Markers.FirstOrDefault (m => m is MessageBubbleTextMarker);
 			if (marker == null)
 				return;
 			
 			marker.SetPrimaryError (task.Description);
 			
-			if (TextEditor.IsComposited) {
+			if (TextEditor != null && TextEditor.IsComposited) {
 				if (messageBubbleHighlightPopupWindow != null)
 					messageBubbleHighlightPopupWindow.Destroy ();
 				messageBubbleHighlightPopupWindow = new MessageBubbleHighlightPopupWindow (this, marker);
@@ -307,31 +307,31 @@ namespace MonoDevelop.SourceEditor
 			DisposeErrorMarkers (); // disposes messageBubbleCache as well.
 			if (IdeApp.Preferences.ShowMessageBubbles == ShowMessageBubbles.Never)
 				return;
-			widget.Document.BeginAtomicUndo ();
-			if (messageBubbleCache != null)
-				messageBubbleCache.Dispose ();
-			messageBubbleCache = new MessageBubbleCache (widget.TextEditor);
-			
-			foreach (Task task in tasks) {
-				if (task.Severity == TaskSeverity.Error || task.Severity == TaskSeverity.Warning) {
-					if (IdeApp.Preferences.ShowMessageBubbles == ShowMessageBubbles.ForErrors && task.Severity == TaskSeverity.Warning)
-						continue;
-					LineSegment lineSegment = widget.Document.GetLine (task.Line);
-					if (lineSegment == null)
-						continue;
-					var marker = currentErrorMarkers.FirstOrDefault (m => m.LineSegment == lineSegment);
-					if (marker != null) {
-						marker.AddError (task.Severity == TaskSeverity.Error, task.Description);
-						continue;
+			using (var undo = Document.OpenUndoGroup ()) {
+				if (messageBubbleCache != null)
+					messageBubbleCache.Dispose ();
+				messageBubbleCache = new MessageBubbleCache (widget.TextEditor);
+				
+				foreach (Task task in tasks) {
+					if (task.Severity == TaskSeverity.Error || task.Severity == TaskSeverity.Warning) {
+						if (IdeApp.Preferences.ShowMessageBubbles == ShowMessageBubbles.ForErrors && task.Severity == TaskSeverity.Warning)
+							continue;
+						LineSegment lineSegment = widget.Document.GetLine (task.Line);
+						if (lineSegment == null)
+							continue;
+						var marker = currentErrorMarkers.FirstOrDefault (m => m.LineSegment == lineSegment);
+						if (marker != null) {
+							marker.AddError (task.Severity == TaskSeverity.Error, task.Description);
+							continue;
+						}
+						MessageBubbleTextMarker errorTextMarker = new MessageBubbleTextMarker (messageBubbleCache, task, lineSegment, task.Severity == TaskSeverity.Error, task.Description);
+						currentErrorMarkers.Add (errorTextMarker);
+						
+						errorTextMarker.IsVisible =  !IdeApp.Preferences.DefaultHideMessageBubbles;
+						widget.Document.AddMarker (lineSegment, errorTextMarker, false);
 					}
-					MessageBubbleTextMarker errorTextMarker = new MessageBubbleTextMarker (messageBubbleCache, task, lineSegment, task.Severity == TaskSeverity.Error, task.Description);
-					currentErrorMarkers.Add (errorTextMarker);
-					
-					errorTextMarker.IsVisible =  !IdeApp.Preferences.DefaultHideMessageBubbles;
-					widget.Document.AddMarker (lineSegment, errorTextMarker, false);
 				}
 			}
-			widget.Document.EndAtomicUndo ();
 			widget.TextEditor.QueueDraw ();
 		}
 		
@@ -386,10 +386,10 @@ namespace MonoDevelop.SourceEditor
 			if (PropertyService.Get ("AutoFormatDocumentOnSave", false)) {
 				var formatter = CodeFormatterService.GetFormatter (Document.MimeType);
 				if (formatter != null && formatter.SupportsOnTheFlyFormatting) {
-					TextEditor.Document.BeginAtomicUndo ();
-					var policies = Project != null ? Project.Policies : null;
-					formatter.OnTheFlyFormat (policies, TextEditor.GetTextEditorData (), 0, Document.Length);
-					TextEditor.Document.EndAtomicUndo ();
+					using (var undo = TextEditor.OpenUndoGroup ()) {
+						var policies = Project != null ? Project.Policies : null;
+						formatter.OnTheFlyFormat (policies, TextEditor.GetTextEditorData (), 0, Document.Length);
+					}
 				}
 			}
 
@@ -1131,15 +1131,12 @@ namespace MonoDevelop.SourceEditor
 			this.Document.Redo ();
 		}
 		
-		public void BeginAtomicUndo ()
-		{
-			this.Document.BeginAtomicUndo ();
-		}
-		public void EndAtomicUndo ()
+		
+		public IDisposable OpenUndoGroup ()
 		{
-			this.Document.EndAtomicUndo ();
+			return Document.OpenUndoGroup ();
 		}
-			
+		
 		public string SelectedText { 
 			get {
 				return TextEditor.IsSomethingSelected ? Document.GetTextAt (TextEditor.SelectionRange) : "";
@@ -1490,26 +1487,26 @@ namespace MonoDevelop.SourceEditor
 			
 			triggerOffset += data.EnsureCaretIsNotVirtual ();
 			if (blockMode) {
-				data.Document.BeginAtomicUndo ();
+				using (var undo = data.OpenUndoGroup ()) {
 
-				int minLine = data.MainSelection.MinLine;
-				int maxLine = data.MainSelection.MaxLine;
-				int column = triggerOffset - data.Document.GetLineByOffset (triggerOffset).Offset;
-				for (int lineNumber = minLine; lineNumber <= maxLine; lineNumber++) {
-					LineSegment lineSegment = data.Document.GetLine (lineNumber);
-					if (lineSegment == null)
-						continue;
-					int offset = lineSegment.Offset + column;
-					data.Replace (offset, length, complete_word);
+					int minLine = data.MainSelection.MinLine;
+					int maxLine = data.MainSelection.MaxLine;
+					int column = triggerOffset - data.Document.GetLineByOffset (triggerOffset).Offset;
+					for (int lineNumber = minLine; lineNumber <= maxLine; lineNumber++) {
+						LineSegment lineSegment = data.Document.GetLine (lineNumber);
+						if (lineSegment == null)
+							continue;
+						int offset = lineSegment.Offset + column;
+						data.Replace (offset, length, complete_word);
+					}
+					data.Caret.Offset = triggerOffset + idx;
+					int minColumn = System.Math.Min (data.MainSelection.Anchor.Column, data.MainSelection.Lead.Column);
+					data.MainSelection.Anchor = new DocumentLocation (data.Caret.Line == minLine ? maxLine : minLine, minColumn);
+					data.MainSelection.Lead = new DocumentLocation (data.Caret.Line, TextEditor.Caret.Column);
+					
+					data.Document.CommitMultipleLineUpdate (data.MainSelection.MinLine, data.MainSelection.MaxLine);
+					data.Caret.PreserveSelection = false;
 				}
-				data.Caret.Offset = triggerOffset + idx;
-				int minColumn = System.Math.Min (data.MainSelection.Anchor.Column, data.MainSelection.Lead.Column);
-				data.MainSelection.Anchor = new DocumentLocation (data.Caret.Line == minLine ? maxLine : minLine, minColumn);
-				data.MainSelection.Lead = new DocumentLocation (data.Caret.Line, TextEditor.Caret.Column);
-				
-				data.Document.CommitMultipleLineUpdate (data.MainSelection.MinLine, data.MainSelection.MaxLine);
-				data.Caret.PreserveSelection = false;
-				data.Document.EndAtomicUndo ();
 			} else {
 				data.Replace (triggerOffset, length, complete_word);
 				data.Caret.Offset = triggerOffset + idx;
@@ -1909,12 +1906,12 @@ namespace MonoDevelop.SourceEditor
 			var policies = Project != null ? Project.Policies : null;
 			var editorData = TextEditor.GetTextEditorData ();
 			if (TextEditor.IsSomethingSelected) {
-				TextEditor.Document.BeginAtomicUndo ();
-				int max = TextEditor.MainSelection.MaxLine;
-				for (int i = TextEditor.MainSelection.MinLine; i <= max; i++) {
-					formatter.CorrectIndenting (policies, editorData, i);
+				using (var undo = TextEditor.OpenUndoGroup ()) {
+					int max = TextEditor.MainSelection.MaxLine;
+					for (int i = TextEditor.MainSelection.MinLine; i <= max; i++) {
+						formatter.CorrectIndenting (policies, editorData, i);
+					}
 				}
-				TextEditor.Document.EndAtomicUndo ();
 			} else {
 				formatter.CorrectIndenting (policies, editorData, TextEditor.Caret.Line);
 			}
@@ -1923,15 +1920,19 @@ namespace MonoDevelop.SourceEditor
 		[CommandHandler (TextEditorCommands.MoveBlockUp)]
 		protected void OnMoveBlockUp ()
 		{
-			TextEditor.RunAction (MiscActions.MoveBlockUp);
-			CorrectIndenting ();
+			using (var undo = TextEditor.OpenUndoGroup ()) {
+				TextEditor.RunAction (MiscActions.MoveBlockUp);
+				CorrectIndenting ();
+			}
 		}
 		
 		[CommandHandler (TextEditorCommands.MoveBlockDown)]
 		protected void OnMoveBlockDown ()
 		{
-			TextEditor.RunAction (MiscActions.MoveBlockDown);
-			CorrectIndenting ();
+			using (var undo = TextEditor.OpenUndoGroup ()) {
+				TextEditor.RunAction (MiscActions.MoveBlockDown);
+				CorrectIndenting ();
+			}
 		}
 		
 		[CommandUpdateHandler (TextEditorCommands.ToggleBlockSelectionMode)]
diff --git a/main/src/addins/MonoDevelop.SourceEditor2/MonoDevelop.SourceEditor/SourceEditorWidget.cs b/main/src/addins/MonoDevelop.SourceEditor2/MonoDevelop.SourceEditor/SourceEditorWidget.cs
index a24146f893..3882d1c556 100644
--- a/main/src/addins/MonoDevelop.SourceEditor2/MonoDevelop.SourceEditor/SourceEditorWidget.cs
+++ b/main/src/addins/MonoDevelop.SourceEditor2/MonoDevelop.SourceEditor/SourceEditorWidget.cs
@@ -1380,34 +1380,33 @@ namespace MonoDevelop.SourceEditor
 			string blockStart = blockStarts[0];
 			string blockEnd = blockEnds[0];
 
-			Document.BeginAtomicUndo ();
-			LineSegment startLine;
-			LineSegment endLine;
-
-			if (TextEditor.IsSomethingSelected) {
-				startLine = Document.GetLineByOffset (textEditor.SelectionRange.Offset);
-				endLine = Document.GetLineByOffset (textEditor.SelectionRange.EndOffset);
-			} else {
-				startLine = endLine = Document.GetLine (textEditor.Caret.Line);
-			}
-			string startLineText = Document.GetTextAt (startLine.Offset, startLine.EditableLength);
-			string endLineText = Document.GetTextAt (endLine.Offset, endLine.EditableLength);
-			if (startLineText.StartsWith (blockStart) && endLineText.EndsWith (blockEnd)) {
-				textEditor.Remove (endLine.Offset + endLine.EditableLength - blockEnd.Length, blockEnd.Length);
-				textEditor.Remove (startLine.Offset, blockStart.Length);
+			using (var undo = Document.OpenUndoGroup ()) {
+				LineSegment startLine;
+				LineSegment endLine;
+	
 				if (TextEditor.IsSomethingSelected) {
-					TextEditor.SelectionAnchor -= blockEnd.Length;
+					startLine = Document.GetLineByOffset (textEditor.SelectionRange.Offset);
+					endLine = Document.GetLineByOffset (textEditor.SelectionRange.EndOffset);
+				} else {
+					startLine = endLine = Document.GetLine (textEditor.Caret.Line);
 				}
-			} else {
-				textEditor.Insert (endLine.Offset + endLine.EditableLength, blockEnd);
-				textEditor.Insert (startLine.Offset, blockStart);
-				if (TextEditor.IsSomethingSelected) {
-					TextEditor.SelectionAnchor += blockEnd.Length;
+				string startLineText = Document.GetTextAt (startLine.Offset, startLine.EditableLength);
+				string endLineText = Document.GetTextAt (endLine.Offset, endLine.EditableLength);
+				if (startLineText.StartsWith (blockStart) && endLineText.EndsWith (blockEnd)) {
+					textEditor.Remove (endLine.Offset + endLine.EditableLength - blockEnd.Length, blockEnd.Length);
+					textEditor.Remove (startLine.Offset, blockStart.Length);
+					if (TextEditor.IsSomethingSelected) {
+						TextEditor.SelectionAnchor -= blockEnd.Length;
+					}
+				} else {
+					textEditor.Insert (endLine.Offset + endLine.EditableLength, blockEnd);
+					textEditor.Insert (startLine.Offset, blockStart);
+					if (TextEditor.IsSomethingSelected) {
+						TextEditor.SelectionAnchor += blockEnd.Length;
+					}
+					
 				}
-				
 			}
-			
-			Document.EndAtomicUndo ();
 		}
 		
 		public void ToggleCodeComment ()
@@ -1470,32 +1469,32 @@ namespace MonoDevelop.SourceEditor
 			LineSegment anchorLine   = TextEditor.IsSomethingSelected ? TextEditor.Document.GetLineByOffset (TextEditor.SelectionAnchor) : null;
 			int         anchorColumn = TextEditor.IsSomethingSelected ? TextEditor.SelectionAnchor - anchorLine.Offset : -1;
 			
-			Document.BeginAtomicUndo ();
-			foreach (LineSegment line in TextEditor.SelectedLines) {
-				TextEditor.Insert (line.Offset, commentTag);
-			}
-			if (TextEditor.IsSomethingSelected) {
-				if (TextEditor.SelectionAnchor < TextEditor.Caret.Offset) {
-					if (anchorColumn != 0) 
-						TextEditor.SelectionAnchor = System.Math.Min (anchorLine.Offset + anchorLine.EditableLength, System.Math.Max (anchorLine.Offset, TextEditor.SelectionAnchor + commentTag.Length));
-				} else {
-					if (anchorColumn != 0) {
-						TextEditor.SelectionAnchor = System.Math.Min (anchorLine.Offset + anchorLine.EditableLength, System.Math.Max (anchorLine.Offset, anchorLine.Offset + anchorColumn + commentTag.Length));
+			using (var undo = Document.OpenUndoGroup ()) {
+				foreach (LineSegment line in TextEditor.SelectedLines) {
+					TextEditor.Insert (line.Offset, commentTag);
+				}
+				if (TextEditor.IsSomethingSelected) {
+					if (TextEditor.SelectionAnchor < TextEditor.Caret.Offset) {
+						if (anchorColumn != 0) 
+							TextEditor.SelectionAnchor = System.Math.Min (anchorLine.Offset + anchorLine.EditableLength, System.Math.Max (anchorLine.Offset, TextEditor.SelectionAnchor + commentTag.Length));
 					} else {
-//						TextEditor.SelectionAnchor = anchorLine.Offset;
+						if (anchorColumn != 0) {
+							TextEditor.SelectionAnchor = System.Math.Min (anchorLine.Offset + anchorLine.EditableLength, System.Math.Max (anchorLine.Offset, anchorLine.Offset + anchorColumn + commentTag.Length));
+						} else {
+	//						TextEditor.SelectionAnchor = anchorLine.Offset;
+						}
 					}
 				}
+				
+				if (TextEditor.Caret.Column != 0) {
+					TextEditor.Caret.PreserveSelection = true;
+					TextEditor.Caret.Column += commentTag.Length;
+					TextEditor.Caret.PreserveSelection = false;
+				}
+				
+				if (TextEditor.IsSomethingSelected) 
+					TextEditor.ExtendSelectionTo (TextEditor.Caret.Offset);
 			}
-			
-			if (TextEditor.Caret.Column != 0) {
-				TextEditor.Caret.PreserveSelection = true;
-				TextEditor.Caret.Column += commentTag.Length;
-				TextEditor.Caret.PreserveSelection = false;
-			}
-			
-			if (TextEditor.IsSomethingSelected) 
-				TextEditor.ExtendSelectionTo (TextEditor.Caret.Offset);
-			Document.EndAtomicUndo ();
 			Document.CommitMultipleLineUpdate (startLineNr, endLineNr);
 		}
 		
@@ -1508,40 +1507,39 @@ namespace MonoDevelop.SourceEditor
 			LineSegment anchorLine   = TextEditor.IsSomethingSelected ? TextEditor.Document.GetLineByOffset (TextEditor.SelectionAnchor) : null;
 			int         anchorColumn = TextEditor.IsSomethingSelected ? TextEditor.SelectionAnchor - anchorLine.Offset : -1;
 			
-			Document.BeginAtomicUndo ();
-			int first = -1;
-			int last  = 0;
-			foreach (LineSegment line in TextEditor.SelectedLines) {
-				string text = Document.GetTextAt (line);
-				string trimmedText = text.TrimStart ();
-				int length = 0;
-				if (trimmedText.StartsWith (commentTag)) {
-					TextEditor.Remove (line.Offset + (text.Length - trimmedText.Length), commentTag.Length);
-					length = commentTag.Length;
+			using (var undo = Document.OpenUndoGroup ()) {
+				int first = -1;
+				int last  = 0;
+				foreach (LineSegment line in TextEditor.SelectedLines) {
+					string text = Document.GetTextAt (line);
+					string trimmedText = text.TrimStart ();
+					int length = 0;
+					if (trimmedText.StartsWith (commentTag)) {
+						TextEditor.Remove (line.Offset + (text.Length - trimmedText.Length), commentTag.Length);
+						length = commentTag.Length;
+					}
+					last = length;
+					if (first < 0)
+						first = last;
 				}
-				last = length;
-				if (first < 0)
-					first = last;
-			}
-			
-			if (TextEditor.IsSomethingSelected) {
-				if (TextEditor.SelectionAnchor < TextEditor.Caret.Offset) {
-					TextEditor.SelectionAnchor = System.Math.Min (anchorLine.Offset + anchorLine.EditableLength, System.Math.Max (anchorLine.Offset, TextEditor.SelectionAnchor - first));
-				} else {
-					TextEditor.SelectionAnchor = System.Math.Min (anchorLine.Offset + anchorLine.EditableLength, System.Math.Max (anchorLine.Offset, anchorLine.Offset + anchorColumn - last));
+				
+				if (TextEditor.IsSomethingSelected) {
+					if (TextEditor.SelectionAnchor < TextEditor.Caret.Offset) {
+						TextEditor.SelectionAnchor = System.Math.Min (anchorLine.Offset + anchorLine.EditableLength, System.Math.Max (anchorLine.Offset, TextEditor.SelectionAnchor - first));
+					} else {
+						TextEditor.SelectionAnchor = System.Math.Min (anchorLine.Offset + anchorLine.EditableLength, System.Math.Max (anchorLine.Offset, anchorLine.Offset + anchorColumn - last));
+					}
 				}
+				
+				if (TextEditor.Caret.Column != DocumentLocation.MinColumn) {
+					TextEditor.Caret.PreserveSelection = true;
+					TextEditor.Caret.Column = System.Math.Max (DocumentLocation.MinColumn, TextEditor.Caret.Column - last);
+					TextEditor.Caret.PreserveSelection = false;
+				}
+				
+				if (TextEditor.IsSomethingSelected) 
+					TextEditor.ExtendSelectionTo (TextEditor.Caret.Offset);
 			}
-			
-			if (TextEditor.Caret.Column != DocumentLocation.MinColumn) {
-				TextEditor.Caret.PreserveSelection = true;
-				TextEditor.Caret.Column = System.Math.Max (DocumentLocation.MinColumn, TextEditor.Caret.Column - last);
-				TextEditor.Caret.PreserveSelection = false;
-			}
-			
-			if (TextEditor.IsSomethingSelected) 
-				TextEditor.ExtendSelectionTo (TextEditor.Caret.Offset);
-		
-			Document.EndAtomicUndo ();
 			Document.CommitMultipleLineUpdate (startLineNr, endLineNr);
 		}