Fixes VSTS Bug 944655: [FATAL] System.ArgumentException exception in

System.Threading.Tasks.Task.WhenAll[PEFile]()

https://devdiv.visualstudio.com/DevDiv/_workitems/edit/944655

That exact crash shouldn't happen anymore in the current version
(definitions is now an ImmutableList and never null) but a crash at
that point should not crash the IDE in any case.

1 files changed, 28 insertions, 23 deletions

diff --git a/main/src/addins/MonoDevelop.AssemblyBrowser/MonoDevelop.AssemblyBrowser/AssemblyBrowserWidget.cs b/main/src/addins/MonoDevelop.AssemblyBrowser/MonoDevelop.AssemblyBrowser/AssemblyBrowserWidget.cs
index a4b6937b34..b34a637c1f 100644
--- a/main/src/addins/MonoDevelop.AssemblyBrowser/MonoDevelop.AssemblyBrowser/AssemblyBrowserWidget.cs
+++ b/main/src/addins/MonoDevelop.AssemblyBrowser/MonoDevelop.AssemblyBrowser/AssemblyBrowserWidget.cs
@@ -917,31 +917,36 @@ namespace MonoDevelop.AssemblyBrowser
 		
 		internal void Open (string url, AssemblyLoader currentAssembly = null, bool expandNode = true)
 		{
-			Task.WhenAll (this.definitions.Select (d => d.LoadingTask)).ContinueWith (d => {
-				// At least one of them failed.
-				if (d.IsFaulted) {
-					LoggingService.LogError ("Failed to load assemblies", d.Exception);
-
-					// It's possible the assembly in which the type we're looking for exists
-					// so try probing for it regardless.
-				}
+			try {
+				Task.WhenAll (this.definitions.Select (d => d.LoadingTask)).ContinueWith (d => {
+					// At least one of them failed.
+					if (d.IsFaulted) {
+						LoggingService.LogError ("Failed to load assemblies", d.Exception);
+
+						// It's possible the assembly in which the type we're looking for exists
+						// so try probing for it regardless.
+					}
 
-				suspendNavigation = false;
-				ITreeNavigator nav = SearchMember (url, expandNode);
-				if (definitions.Count == 0) // we've been disposed
-					return;
-				if (nav != null)
-					return;
-				try {
-					if (currentAssembly != null) {
-						OpenFromAssembly (url, currentAssembly);
-					} else {
-						OpenFromAssemblyNames (url);
+					suspendNavigation = false;
+					ITreeNavigator nav = SearchMember (url, expandNode);
+					if (definitions.Count == 0) // we've been disposed
+						return;
+					if (nav != null)
+						return;
+					try {
+						if (currentAssembly != null) {
+							OpenFromAssembly (url, currentAssembly);
+						} else {
+							OpenFromAssemblyNames (url);
+						}
+					} catch (Exception e) {
+						LoggingService.LogError ("Error while opening the assembly browser with id:" + url, e);
 					}
-				} catch (Exception e) {
-					LoggingService.LogError ("Error while opening the assembly browser with id:" + url, e);
-				}
-			}, Runtime.MainTaskScheduler).Ignore ();
+				}, Runtime.MainTaskScheduler).Ignore ();
+			} catch (Exception e) {
+				LoggingService.LogError ("Error while opening assembly :" + url);
+				MessageService.ShowError (GettextCatalog.GetString ("Error while opening assembly {0}.", url), e);
+			}
 		}
 
 		void OpenFromAssembly (string url, AssemblyLoader currentAssembly, bool expandNode = true)