Enabled exception propagation from WinRT callbacks

Author: Sergio0694

CommunityToolkit.WinUI/Extensions/DispatcherQueueExtensions{T}.cs

@@ -112,13 +112,13 @@ public static unsafe bool TryEnqueue<T1, T2>(this DispatcherQueue dispatcherQueu
         /// <exception cref="Exception">Thrown when the enqueue operation fails.</exception>
         private static unsafe bool TryEnqueue(DispatcherQueue dispatcherQueue, IDispatcherQueueHandler* dispatcherQueueHandler)
         {
-            IDispatcherQueue* dispatcherQueuePtr = (IDispatcherQueue*)((IWinRTObject)dispatcherQueue).NativeObject.ThisPtr;
-
             bool success;
             int hResult;
 
             try
             {
+                IDispatcherQueue* dispatcherQueuePtr = (IDispatcherQueue*)((IWinRTObject)dispatcherQueue).NativeObject.ThisPtr;
+
                 hResult = dispatcherQueuePtr->TryEnqueue(dispatcherQueueHandler, (byte*)&success);
 
                 GC.KeepAlive(dispatcherQueue);
@@ -146,13 +146,13 @@ private static unsafe bool TryEnqueue(DispatcherQueue dispatcherQueue, IDispatch
         /// <exception cref="Exception">Thrown when the enqueue operation fails.</exception>
         private static unsafe bool TryEnqueue(DispatcherQueue dispatcherQueue, DispatcherQueuePriority priority, IDispatcherQueueHandler* dispatcherQueueHandler)
         {
-            IDispatcherQueue* dispatcherQueuePtr = (IDispatcherQueue*)((IWinRTObject)dispatcherQueue).NativeObject.ThisPtr;
-
             bool success;
             int hResult;
 
             try
             {
+                IDispatcherQueue* dispatcherQueuePtr = (IDispatcherQueue*)((IWinRTObject)dispatcherQueue).NativeObject.ThisPtr;
+
                 hResult = dispatcherQueuePtr->TryEnqueueWithPriority(priority, dispatcherQueueHandler, (byte*)&success);
 
                 GC.KeepAlive(dispatcherQueue);

CommunityToolkit.WinUI/Extensions/Interop/DispatcherQueueProxyHandler1.cs

@@ -6,6 +6,7 @@
 using System.Runtime.CompilerServices;
 using System.Runtime.InteropServices;
 using System.Threading;
+using WinRT;
 using static CommunityToolkit.WinUI.Interop.Windows;
 
 #nullable enable
@@ -179,8 +180,11 @@ public static int Invoke(DispatcherQueueProxyHandler1* @this)
                     // need to make the proxy type itself generic, so without knowing the actual type argument.
                     Unsafe.As<DispatcherQueueHandler<object>>(callback)(state);
                 }
-                catch
+                catch (Exception e)
                 {
+                    ExceptionHelpers.SetErrorInfo(e);
+
+                    return ExceptionHelpers.GetHRForException(e);
                 }
 
                 return S_OK;

CommunityToolkit.WinUI/Extensions/Interop/DispatcherQueueProxyHandler2.cs

@@ -6,6 +6,7 @@
 using System.Runtime.CompilerServices;
 using System.Runtime.InteropServices;
 using System.Threading;
+using WinRT;
 using static CommunityToolkit.WinUI.Interop.Windows;
 
 #nullable enable
@@ -184,8 +185,11 @@ public static int Invoke(DispatcherQueueProxyHandler2* @this)
                     // Same optimization as in DispatcherQueueProxyHandler1
                     Unsafe.As<DispatcherQueueHandler<object, object>>(callback)(state1, state2);
                 }
-                catch
+                catch (Exception e)
                 {
+                    ExceptionHelpers.SetErrorInfo(e);
+
+                    return ExceptionHelpers.GetHRForException(e);
                 }
 
                 return S_OK;