Merge pull request #4184 from mono/d15_6-fix581661monodevelop-7.4.1.48

[15.6] Fixes VSTS 581661: [Feedback] /* */ Comments slow or non responsive

4 files changed, 68 insertions, 13 deletions

diff --git a/main/src/addins/MonoDevelop.SourceEditor2/Mono.TextEditor/Gui/TextViewMargin.cs b/main/src/addins/MonoDevelop.SourceEditor2/Mono.TextEditor/Gui/TextViewMargin.cs
index f750fcd8b1..ca15510bb5 100644
--- a/main/src/addins/MonoDevelop.SourceEditor2/Mono.TextEditor/Gui/TextViewMargin.cs
+++ b/main/src/addins/MonoDevelop.SourceEditor2/Mono.TextEditor/Gui/TextViewMargin.cs
@@ -332,7 +332,6 @@ namespace Mono.TextEditor
 		{
 			for (int i = 0; i < e.TextChanges.Count; ++i) {
 				var change = e.TextChanges[i];
-				RemoveCachedLine (Document.OffsetToLineNumber (change.NewOffset));
 				if (mouseSelectionMode == MouseSelectionMode.Word && change.Offset < mouseWordStart) {
 					int delta = change.ChangeDelta;
 					mouseWordStart += delta;
@@ -1322,12 +1321,27 @@ namespace Mono.TextEditor
 			cacheSrc = new CancellationTokenSource ();
 			cachedLines.Clear ();
 		}
-
 		public void PurgeLayoutCache ()
 		{
 			DisposeLayoutDict ();
 		}
 
+		void PurgeLayoutCacheAfter (int lineNumber)
+		{
+			foreach (var descr in layoutDict.ToArray()) {
+				if (descr.Key >= lineNumber) {
+					descr.Value.Dispose ();
+					layoutDict.Remove (descr.Key);
+				}
+			}
+
+			foreach (var descr in cachedLines.ToArray()) {
+				if (descr.Key >= lineNumber) {
+					cachedLines.Remove (descr.Key);
+				}
+			}
+		}
+
 		class ChunkDescriptor : LineDescriptor
 		{
 			public List<MonoDevelop.Ide.Editor.Highlighting.ColoredSegment> Chunk {
@@ -1353,16 +1367,44 @@ namespace Mono.TextEditor
 			var token = cacheSrc.Token;
 			var task = doc.SyntaxMode.GetHighlightedLineAsync (line, token);
 			if (task.IsCompleted) {
-				cachedLines [lineNumber] = task.Result;
-				return Tuple.Create (TrimChunks (task.Result.Segments, offset - line.Offset, length), true);
+				if (task.Result != null) {
+					UpdateLineHighlight (lineNumber, result, task.Result);
+					return Tuple.Create (TrimChunks (task.Result.Segments, offset - line.Offset, length), true);
+				}
 			}
 			task.ContinueWith (t => {
-				cachedLines [lineNumber] = t.Result;
-				Document.CommitLineUpdate (lineNumber); // Required for highlighting updates
+				if (t.Result == null)
+					return;
+				if (UpdateLineHighlight (lineNumber, result, t.Result)) {
+					RemoveCachedLine (lineNumber);
+					Document.CommitLineUpdate (line);
+				}
 			}, token, TaskContinuationOptions.OnlyOnRanToCompletion, Runtime.MainTaskScheduler);
 			return Tuple.Create (new List<ColoredSegment> (new [] { new ColoredSegment (0, line.Length, ScopeStack.Empty) }), false);
 		}
 
+		bool UpdateLineHighlight (int lineNumber, HighlightedLine oldLine, HighlightedLine newLine)
+		{
+			if (oldLine != null && ShouldUpdateSpan (oldLine, newLine)) {
+				PurgeLayoutCacheAfter (lineNumber);
+				cachedLines [lineNumber] = newLine;
+				textEditor.QueueDraw ();
+				return false;
+			}
+			cachedLines [lineNumber] = newLine;
+			return true;
+		}
+
+		static bool ShouldUpdateSpan (HighlightedLine line1, HighlightedLine line2)
+		{
+			if (line1.IsContinuedBeyondLineEnd != line2.IsContinuedBeyondLineEnd)
+				return true;
+			if (line1.IsContinuedBeyondLineEnd == true) {
+				return line1.Segments.Last ().ScopeStack.Peek () != line2.Segments.Last ().ScopeStack.Peek ();
+			}
+			return false;
+		}
+
 		internal static List<ColoredSegment> TrimChunks (IReadOnlyList<ColoredSegment> segments, int offset, int length)
 		{
 			var result = new List<ColoredSegment> ();
diff --git a/main/src/core/Mono.TextEditor.Shared/Mono.TextEditor/Document/DocumentUpdateRequest.cs b/main/src/core/Mono.TextEditor.Shared/Mono.TextEditor/Document/DocumentUpdateRequest.cs
index 2cd7c20c7c..dded9bdb91 100644
--- a/main/src/core/Mono.TextEditor.Shared/Mono.TextEditor/Document/DocumentUpdateRequest.cs
+++ b/main/src/core/Mono.TextEditor.Shared/Mono.TextEditor/Document/DocumentUpdateRequest.cs
@@ -84,12 +84,8 @@ namespace Mono.TextEditor
 		public override void Update (MonoTextEditor editor)
 		{
 			if (start == end) {
-				editor.TextViewMargin.RemoveCachedLine (start);
 				editor.RedrawLine (start);
 			} else {
-				for (int i = start; i <= end; i++) {
-					editor.TextViewMargin.RemoveCachedLine (i);
-				}
 				editor.RedrawLines (start, end);
 			}
 		}
diff --git a/main/src/core/MonoDevelop.Ide/MonoDevelop.Ide.Editor.Highlighting/ISyntaxHighlighting.cs b/main/src/core/MonoDevelop.Ide/MonoDevelop.Ide.Editor.Highlighting/ISyntaxHighlighting.cs
index 34b6f7d4f3..215e49ba47 100644
--- a/main/src/core/MonoDevelop.Ide/MonoDevelop.Ide.Editor.Highlighting/ISyntaxHighlighting.cs
+++ b/main/src/core/MonoDevelop.Ide/MonoDevelop.Ide.Editor.Highlighting/ISyntaxHighlighting.cs
@@ -31,6 +31,7 @@ using MonoDevelop.Core.Text;
 using System.Collections.Immutable;
 using System.Threading.Tasks;
 using System.Threading;
+using System.Linq;
 
 namespace MonoDevelop.Ide.Editor.Highlighting
 {
@@ -41,6 +42,20 @@ namespace MonoDevelop.Ide.Editor.Highlighting
 		/// The segment offsets are 0 at line start regardless of where the line is inside the document.
 		/// </summary>
 		public IReadOnlyList<ColoredSegment> Segments { get; private set; }
+
+		bool? isContinuedBeyondLineEnd;
+		public bool? IsContinuedBeyondLineEnd {
+			get {
+				if (isContinuedBeyondLineEnd.HasValue)
+					return isContinuedBeyondLineEnd.Value;
+				var result = Segments.Count > 0 ? TextSegment.Length < Segments.Last ().EndOffset : false;
+				return isContinuedBeyondLineEnd = result;
+			}
+			set {
+				isContinuedBeyondLineEnd = value;
+			}
+		}
+
 		public HighlightedLine (ISegment textSegment, IReadOnlyList<ColoredSegment> segments)
 		{
 			TextSegment = textSegment;
@@ -89,4 +104,4 @@ namespace MonoDevelop.Ide.Editor.Highlighting
 		{

 		}
 	}
-}
\ No newline at end of file
+}
diff --git a/main/src/core/MonoDevelop.Ide/MonoDevelop.Ide.Editor.Highlighting/SyntaxHighlighting.cs b/main/src/core/MonoDevelop.Ide/MonoDevelop.Ide.Editor.Highlighting/SyntaxHighlighting.cs
index c8340e77e8..153a651a5a 100644
--- a/main/src/core/MonoDevelop.Ide/MonoDevelop.Ide.Editor.Highlighting/SyntaxHighlighting.cs
+++ b/main/src/core/MonoDevelop.Ide/MonoDevelop.Ide.Editor.Highlighting/SyntaxHighlighting.cs
@@ -188,7 +188,7 @@ namespace MonoDevelop.Ide.Editor.Highlighting
 				int lastMatch = -1;
 				var highlightedSegment = new TextSegment (startOffset, length);
 				string lineText = text.GetTextAt (startOffset, length);
-
+				var initialState = state.Clone ();
 				int timeoutOccursAt;
 				unchecked {
 					timeoutOccursAt = Environment.TickCount + (int)matchTimeout.TotalMilliseconds;
@@ -330,7 +330,9 @@ namespace MonoDevelop.Ide.Editor.Highlighting
 					segments.Add (new ColoredSegment (curSegmentOffset, endOffset - curSegmentOffset, ScopeStack));
 				}
 
-				return Task.FromResult (new HighlightedLine (highlightedSegment, segments));
+				return Task.FromResult (new HighlightedLine (highlightedSegment, segments) {
+					IsContinuedBeyondLineEnd = !initialState.Equals (state)
+				});
 			}
 
 			void PushStack (SyntaxMatch curMatch, IEnumerable<SyntaxContext> nextContexts)