Updated InvalidHandleEventException Logic

Author: TheCodeTraveler

Src/AsyncAwaitBestPractices.UnitTests/WeakEventManager/Tests_WeakEventManager_EventHandler.cs

@@ -116,7 +116,7 @@ void HandleTestEvent(object? sender, EventArgs e)
         }
 
         [Test]
-        public void WeakEventManager_HandleEvent_InvalidHandleEvent()
+        public void WeakEventManager_HandleEvent_InvalidHandleEventName()
         {
             //Arrange
             TestEvent += HandleTestEvent;
@@ -270,5 +270,22 @@ public void WeakEventManager_RemoveventHandler_WhiteSpaceEventName()
             Assert.Throws<ArgumentNullException>(() => TestWeakEventManager.RemoveEventHandler(null, " "), "Value cannot be null.\nParameter name: eventName");
 #pragma warning enable CS8625
         }
+
+        [Test]
+        public void WeakEventManager_HandleEvent_InvalidHandleEvent()
+        {
+            //Arrange
+            TestEvent += HandleTestEvent;
+            bool didEventFire = false;
+
+            void HandleTestEvent(object sender, EventArgs e) => didEventFire = true;
+
+            //Act
+
+            //Assert
+            Assert.Throws<InvalidHandleEventException>(() => TestWeakEventManager.HandleEvent(nameof(TestEvent)));
+            Assert.IsFalse(didEventFire);
+            TestEvent -= HandleTestEvent;
+        }
     }
 }

Src/AsyncAwaitBestPractices.UnitTests/WeakEventManager/Tests_WeakEventManager_EventHandlerT.cs

@@ -259,5 +259,22 @@ public void WeakEventManagerT_RemoveventHandler_WhiteSpaceEventName()
             //Assert
             Assert.Throws<ArgumentNullException>(() => TestStringWeakEventManager.AddEventHandler(s => { var temp = s; }, string.Empty), "Value cannot be null.\nParameter name: eventName");
         }
+
+        [Test]
+        public void WeakEventManagerT_HandleEvent_InvalidHandleEvent()
+        {
+            //Arrange
+            TestStringEvent += HandleTestStringEvent;
+            bool didEventFire = false;
+
+            void HandleTestStringEvent(object sender, string e) => didEventFire = true;
+
+            //Act
+
+            //Assert
+            Assert.Throws<InvalidHandleEventException>(() => TestStringWeakEventManager.HandleEvent("", nameof(TestStringEvent)));
+            Assert.IsFalse(didEventFire);
+            TestStringEvent -= HandleTestStringEvent;
+        }
     }
 }

Src/AsyncAwaitBestPractices/WeakEventManager/EventManagerService.cs

@@ -53,13 +53,14 @@ internal static void HandleEvent(in string eventName, in object? sender, in obje
                     Tuple<object?, MethodInfo> tuple = toRaise[i];
                     tuple.Item2.Invoke(tuple.Item1, new[] { sender, eventArgs });
                 }
-                catch (TargetParameterCountException e) when (e.Message.Contains("Parameter count mismatch"))
+                catch (TargetParameterCountException e)
                 {
                     throw new InvalidHandleEventException("Parameter count mismatch. If invoking an `event Action` use `HandleEvent(string eventName)` or if invoking an `event Action<T>` use `HandleEvent(object eventArgs, string eventName)`instead.", e);
                 }
             }
         }
 
+        //From ViewModel
         internal static void HandleEvent(in string eventName, in object? actionEventArgs, in Dictionary<string, List<Subscription>> eventHandlers)
         {
             AddRemoveEvents(eventName, eventHandlers, out var toRaise);
@@ -71,7 +72,7 @@ internal static void HandleEvent(in string eventName, in object? actionEventArgs
                     var tuple = toRaise[i];
                     tuple.Item2.Invoke(tuple.Item1, new[] { actionEventArgs });
                 }
-                catch (TargetParameterCountException e) when (e.Message.Contains("Parameter count mismatch"))
+                catch (TargetParameterCountException e)
                 {
                     throw new InvalidHandleEventException("Parameter count mismatch. If invoking an `event EventHandler` use `HandleEvent(object sender, TEventArgs eventArgs, string eventName)` or if invoking an `event Action` use `HandleEvent(string eventName)`instead.", e);
                 }
@@ -89,7 +90,7 @@ internal static void HandleEvent(in string eventName, in Dictionary<string, List
                     var tuple = toRaise[i];
                     tuple.Item2.Invoke(tuple.Item1, null);
                 }
-                catch (TargetParameterCountException e) when (e.Message.Contains("Parameter count mismatch"))
+                catch (TargetParameterCountException e)
                 {
                     throw new InvalidHandleEventException("Parameter count mismatch. If invoking an `event EventHandler` use `HandleEvent(object sender, TEventArgs eventArgs, string eventName)` or if invoking an `event Action<T>` use `HandleEvent(object eventArgs, string eventName)`instead.", e);
                 }

Src/HackerNews/ViewModels/NewsViewModel_GoodAsyncAwaitPractices.cs

@@ -44,7 +44,7 @@ public bool IsListRefreshing
             get => _isListRefreshing;
             set => SetProperty(ref _isListRefreshing, value);
         }
- 
+
         async Task ExecuteRefreshCommand()
         {
             IsListRefreshing = true;
@@ -87,7 +87,7 @@ async Task<List<string>> GetTopStoryIDs()
             catch (Exception e)
             {
                 OnErrorOccurred(e.Message);
-                return new List<string>();
+                return Enumerable.Empty<string>().ToList();
             }
         }