Cancel currently running search when a new search is started.

src/AddIns/BackendBindings/CSharpBinding/Project/Src/Parser/CSharpSymbolSearch.cs

@@ -78,7 +78,13 @@ namespace CSharpBinding
 								CancellationToken = cancellationToken
 							},
 							delegate (string fileName) {
+								try {
 									FindReferencesInFile(args, searchScope, FileName.Create(fileName), callback, cancellationToken);
+								} catch (OperationCanceledException) {
+									throw;
+								} catch (Exception ex) {
+									throw new ApplicationException("Error searching in file '" + fileName + "'", ex);
+								}
 								lock (progressLock)
 									args.ProgressMonitor.Progress += workAmountInverse;
 							});

src/AddIns/Misc/SearchAndReplace/Project/Gui/DefaultSearchResult.cs

@@ -54,7 +54,11 @@ namespace SearchAndReplace
 			return resultsTreeViewInstance;
 		}
 		
-		static IList toolbarItems;
+		public virtual void OnDeactivate()
+		{
+		}
+		
+		static IList<object> toolbarItems;
 		
 		public virtual IList GetToolbarItems()
 		{
@@ -122,7 +126,8 @@ namespace SearchAndReplace
 				collapseAll.Click += delegate { ExpandCollapseAll(false); };
 				toolbarItems.Add(collapseAll);
 			}
-			return toolbarItems;
+			// Copy the list to avoid modifications to the static list
+			return new List<object>(toolbarItems);
 		}
 		
 		static void SetCheckedItem(MenuItem newTarget, ContextMenu menu)

src/AddIns/Misc/SearchAndReplace/Project/Gui/ObserverSearchResult.cs

@@ -37,6 +37,13 @@ namespace SearchAndReplace
 			return resultsTreeViewInstance;
 		}
 		
+		public override void OnDeactivate()
+		{
+			if (!finished)
+				StopButtonClick(null, null);
+			base.OnDeactivate();
+		}
+		
 		public override IList GetToolbarItems()
 		{
 			var items = base.GetToolbarItems();

src/AddIns/Misc/SearchAndReplace/Project/Gui/SearchRootNode.cs

@@ -19,9 +19,19 @@ namespace SearchAndReplace
 		ObservableCollection<SearchFileNode> fileNodes;
 		ObservableCollection<SearchProjectNode> projectNodes;
 		ObservableCollection<SearchProjectNode> projectAndFileNodes;
+		bool wasCancelled;
 		
 		public string Title { get; private set; }
-		public bool WasCancelled { get; set; }
+		
+		public bool WasCancelled {
+			get {
+				return wasCancelled;
+			}
+			set {
+				wasCancelled = value;
+				InvalidateText();
+			}
+		}
 		
 		public SearchRootNode(string title, IList<SearchResultMatch> results)
 		{

src/Main/Base/Project/Editor/Search/ISearchResult.cs

@@ -26,6 +26,12 @@ namespace ICSharpCode.SharpDevelop.Editor.Search
 		/// </summary>
 		object GetControl();
 		
+		/// <summary>
+		/// Notifies the search that it is no longer active (another search result will be activated in the search results pad).
+		/// GetControl() will be called if the search result is activated again.
+		/// </summary>
+		void OnDeactivate();
+		
 		/// <summary>
 		/// Gets the items for the toolbar that are visible only for this search result.
 		/// </summary>

src/Main/Base/Project/Editor/Search/SearchResultsPad.cs

@@ -66,6 +66,7 @@ namespace ICSharpCode.SharpDevelop.Editor.Search
 			}
 		}
 		
+		ISearchResult activeSearchResult;
 		List<ISearchResult> lastSearches = new List<ISearchResult>();
 		
 		public IEnumerable<ISearchResult> LastSearches {
@@ -75,6 +76,10 @@ namespace ICSharpCode.SharpDevelop.Editor.Search
 		public void ClearLastSearchesList()
 		{
 			lastSearches.Clear();
+			if (activeSearchResult != null) {
+				activeSearchResult.OnDeactivate();
+				activeSearchResult = null;
+			}
 			SD.WinForms.SetContent(contentPlaceholder, null);
 		}
 		
@@ -95,6 +100,12 @@ namespace ICSharpCode.SharpDevelop.Editor.Search
 			while (lastSearches.Count > 15)
 				lastSearches.RemoveAt(15);
 			
+			if (activeSearchResult != result) {
+				if (activeSearchResult != null) {
+					activeSearchResult.OnDeactivate();
+				}
+				activeSearchResult = result;
+			}
 			SD.WinForms.SetContent(contentPlaceholder, result.GetControl());
 			
 			toolBar.Items.Clear();
@@ -206,6 +217,10 @@ namespace ICSharpCode.SharpDevelop.Editor.Search
 			{
 				return null;
 			}
+			
+			public void OnDeactivate()
+			{
+			}
 		}
 	}
 }