Merge pull request #7069 from mono/master-vsts749965

Fixes VSTS Bug 749965: Fatal error on copy + paste in

2 files changed, 20 insertions, 10 deletions

diff --git a/main/src/core/Mono.TextEditor.Shared/Mono.TextEditor/CaretImpl.ITextCaret.cs b/main/src/core/Mono.TextEditor.Shared/Mono.TextEditor/CaretImpl.ITextCaret.cs
index 6f121254c2..113f6992ac 100644
--- a/main/src/core/Mono.TextEditor.Shared/Mono.TextEditor/CaretImpl.ITextCaret.cs
+++ b/main/src/core/Mono.TextEditor.Shared/Mono.TextEditor/CaretImpl.ITextCaret.cs
@@ -29,6 +29,7 @@ using Microsoft.VisualStudio.Text;
 using Microsoft.VisualStudio.Text.Editor;
 using Microsoft.VisualStudio.Text.Formatting;
 using MonoDevelop.Ide.Editor;
+using MonoDevelop.Core;
 
 namespace Mono.TextEditor
 {
@@ -116,8 +117,14 @@ namespace Mono.TextEditor
 			insertionPoint = vsp;
 			if (args.CaretChangeReason == CaretChangeReason.Movement) {
 				oldCaretLocation = args.Location;
-				var oldOffset = TextEditor.LocationToOffset (args.Location);
-				var snapshotPoint = new SnapshotPoint (TextEditor.TextSnapshot, oldOffset);
+				var snapShot = args.Snapshot;
+				var snapshotLine = snapShot.GetLineFromLineNumber (args.Location.Line - 1);
+				if (snapshotLine == null) {
+					LoggingService.LogError ("PositionChanged_ITextCaret line number : " + args.Location.Line + " is out of range.");
+					return;
+				}
+				var oldOffset = snapshotLine.Start.Position + Math.Min (snapshotLine.Length, args.Location.Column - 1);
+				var snapshotPoint = new SnapshotPoint (snapShot, oldOffset);
 				var mappingPoint = TextEditor.BufferGraph.CreateMappingPoint (snapshotPoint, PointTrackingMode.Positive);
 				var oldCaretPosition = new CaretPosition (vsp, mappingPoint, _caretAffinity);
 				var eventArgs = new CaretPositionChangedEventArgs (TextEditor, oldCaretPosition, ((ITextCaret)this).Position);
diff --git a/main/src/core/Mono.TextEditor.Shared/Mono.TextEditor/CaretImpl.cs b/main/src/core/Mono.TextEditor.Shared/Mono.TextEditor/CaretImpl.cs
index 798c42b28d..7ad29ede3d 100644
--- a/main/src/core/Mono.TextEditor.Shared/Mono.TextEditor/CaretImpl.cs
+++ b/main/src/core/Mono.TextEditor.Shared/Mono.TextEditor/CaretImpl.cs
@@ -39,7 +39,9 @@ namespace Mono.TextEditor
 		bool autoScrollToCaret = true;
 		
 		CaretMode mode;
-		
+
+		ITextSnapshot currentBuffer;
+
 		int line = DocumentLocation.MinLine;
 		public override int Line {
 			get {
@@ -54,7 +56,7 @@ namespace Mono.TextEditor
 					CheckLine ();
 					SetColumn ();
 					UpdateCaretOffset ();
-					OnPositionChanged (new CaretLocationEventArgs (old, CaretChangeReason.Movement));
+					OnPositionChanged (new CaretLocationEventArgs (old, currentBuffer ?? TextEditorData.Document.TextBuffer.CurrentSnapshot, CaretChangeReason.Movement));
 				}
 			}
 		}
@@ -73,7 +75,7 @@ namespace Mono.TextEditor
 					CheckColumn ();
 					SetDesiredColumn ();
 					UpdateCaretOffset ();
-					OnPositionChanged (new CaretLocationEventArgs (old, CaretChangeReason.Movement));
+					OnPositionChanged (new CaretLocationEventArgs (old, currentBuffer ?? TextEditorData.Document.TextBuffer.CurrentSnapshot, CaretChangeReason.Movement));
 				}
 			}
 		}
@@ -93,7 +95,7 @@ namespace Mono.TextEditor
 					CheckColumn ();
 					SetDesiredColumn ();
 					UpdateCaretOffset ();
-					OnPositionChanged (new CaretLocationEventArgs (old, CaretChangeReason.Movement));
+					OnPositionChanged (new CaretLocationEventArgs (old, currentBuffer ?? TextEditorData.Document.TextBuffer.CurrentSnapshot, CaretChangeReason.Movement));
 				}
 			}
 		}
@@ -119,7 +121,7 @@ namespace Mono.TextEditor
 				CheckLine ();
 				CheckColumn ();
 				SetDesiredColumn ();
-				OnPositionChanged (new CaretLocationEventArgs (old, CaretChangeReason.Movement));
+				OnPositionChanged (new CaretLocationEventArgs (old, currentBuffer ?? TextEditorData.Document.TextBuffer.CurrentSnapshot, CaretChangeReason.Movement));
 			}
 		}
 
@@ -270,7 +272,7 @@ namespace Mono.TextEditor
 			}
 
 			UpdateCaretOffset ();
-			OnPositionChanged (new CaretLocationEventArgs (old, CaretChangeReason.Movement));
+			OnPositionChanged (new CaretLocationEventArgs (old, currentBuffer ?? TextEditorData.Document.TextBuffer.CurrentSnapshot, CaretChangeReason.Movement));
 		}
 
 		void SetDesiredColumn ()
@@ -301,7 +303,7 @@ namespace Mono.TextEditor
 			var old = Location;
 			DesiredColumn = desiredColumn;
 			SetColumn ();
-			OnPositionChanged (new CaretLocationEventArgs (old, CaretChangeReason.Movement));
+			OnPositionChanged (new CaretLocationEventArgs (old, currentBuffer ?? TextEditorData.Document.TextBuffer.CurrentSnapshot, CaretChangeReason.Movement));
 		}
 		
 		public override string ToString ()
@@ -330,6 +332,7 @@ namespace Mono.TextEditor
 			TextEditorData.Document.EnsureOffsetIsUnfolded (Offset);
 			base.OnPositionChanged (args);
 			PositionChanged_ITextCaret (args);
+			currentBuffer = TextEditorData.Document.TextBuffer.CurrentSnapshot;
 		}
 		
 		protected virtual void OnModeChanged ()
@@ -386,7 +389,7 @@ namespace Mono.TextEditor
 
 			SetDesiredColumn ();
 			UpdateCaretOffset ();
-			OnPositionChanged (new CaretLocationEventArgs (old, CaretChangeReason.BufferChange));
+			OnPositionChanged (new CaretLocationEventArgs (old, currentBuffer ?? TextEditorData.Document.TextBuffer.CurrentSnapshot, CaretChangeReason.BufferChange));
 		}
 
 		public void SetDocument (TextDocument doc)