Merge pull request #6699 from Troy-Ferrell/users/trferrel/eventhandler-try-catch

Don't crash on global listeners

Author: Troy-Ferrell

Assets/MixedRealityToolkit.Tests/PlayModeTests/Components/TestInputGlobalListener.cs

@@ -1,6 +1,7 @@
 // Copyright (c) Microsoft Corporation. All rights reserved.
 // Licensed under the MIT License. See LICENSE in the project root for license information.
 
+using System;
 using System.Collections.Generic;
 using Microsoft.MixedReality.Toolkit.Input;
 using Microsoft.MixedReality.Toolkit.Utilities;
@@ -93,7 +94,7 @@ public void OnPointerUp(MixedRealityPointerEventData eventData)
             pointerUpCount++;
         }
 
-        public void OnPointerClicked(MixedRealityPointerEventData eventData)
+        public virtual void OnPointerClicked(MixedRealityPointerEventData eventData)
         {
             pointerClickedCount++;
         }
@@ -104,6 +105,15 @@ public void OnSpeechKeywordRecognized(SpeechEventData eventData)
         }
     }
 
+    internal class TestInputGlobalListenerException : TestInputGlobalListener
+    {
+        public const string ExceptionMessage = "Test exception thrown during event fired for global listener";
+        public override void OnPointerClicked(MixedRealityPointerEventData eventData)
+        {
+            throw new Exception(ExceptionMessage);
+        }
+    }
+
     internal class TestInputGlobalListenerObjectBased : TestInputGlobalListener
     {
         TestInputGlobalListenerObjectBased()

Assets/MixedRealityToolkit.Tests/PlayModeTests/InputEventSystemTests.cs

@@ -344,6 +344,30 @@ public IEnumerator TestInputSystemGlobalHandlerListener()
             Object.Destroy(object1);
             yield return null;
         }
+
+        /// <summary>
+        /// Test input system catches exception thrown in global listener responding to input event and that
+        /// the input system does not crash accordingly as well
+        /// </summary>
+        [UnityTest]
+        public IEnumerator TestGlobalListenerExceptionThrown()
+        {
+            var inputSystem = CoreServices.InputSystem;
+
+            var object1 = new GameObject("Object");
+            var listener = object1.AddComponent<TestInputGlobalListenerException>();
+
+            yield return null;
+
+            // Emit pointer event, which should be received by global handler
+            inputSystem.RaisePointerClicked(inputSystem.GazeProvider.GazePointer, MixedRealityInputAction.None, 1);
+
+            LogAssert.Expect(LogType.Exception, $"Exception: {TestInputGlobalListenerException.ExceptionMessage}");
+
+            Object.Destroy(object1);
+
+            yield return null;
+        }
     }
 }
 #endif

Assets/MixedRealityToolkit/Services/BaseEventSystem.cs

@@ -94,7 +94,15 @@ public virtual void HandleEvent<T>(BaseEventData eventData, ExecuteEvents.EventF
                         continue;
                     }
 
-                    eventHandler.Invoke((T)handlerEntry.handler, eventData);
+                    try
+                    {
+                        // Ensure client code does not crash our input system
+                        eventHandler.Invoke((T)handlerEntry.handler, eventData);
+                    }
+                    catch (Exception ex)
+                    {
+                        Debug.LogException(ex);
+                    }
                 }
             }