Fix #511: Automatic code formatting grabs closing curly brackets when adding properties

src/AddIns/BackendBindings/CSharpBinding/Project/Src/FormattingStrategy/CSharpFormatter.cs

@@ -31,11 +31,17 @@ namespace CSharpBinding.FormattingStrategy
 		/// </summary>
 		public static void Format(ITextEditor editor, int offset, int length, CSharpFormattingOptionsContainer optionsContainer)
 		{
+			SyntaxTree syntaxTree = SyntaxTree.Parse(editor.Document);
+			if (syntaxTree.Errors.Count > 0) {
+				// Don't format files containing syntax errors!
+				return;
+			}
+			
 			TextEditorOptions editorOptions = editor.ToEditorOptions();
 			optionsContainer.CustomizeEditorOptions(editorOptions);
 			var formatter = new CSharpFormatter(optionsContainer.GetEffectiveOptions(), editorOptions);
 			formatter.AddFormattingRegion(new DomRegion(editor.Document.GetLocation(offset), editor.Document.GetLocation(offset + length)));
-			var changes = formatter.AnalyzeFormatting(editor.Document, SyntaxTree.Parse(editor.Document));
+			var changes = formatter.AnalyzeFormatting(editor.Document, syntaxTree);
 			changes.ApplyChanges(offset, length);
 		}
 	}