Add ThrowsAsync for non-generic ValueTask (#1235)

CHANGELOG.md

@@ -11,6 +11,7 @@ The format is loosely based on [Keep a Changelog](http://keepachangelog.com/en/1
 
 * `Mock<T>.RaiseAsync` method for raising "async" events, i.e. events that use a `Func<..., Task>` or `Func<..., ValueTask>` delegate. (@stakx, #1313)
 * `setup.Verifiable(Times times, [string failMessage])` method to specify the expected number of calls upfront. `mock.Verify[All]` can then be used to check whether the setup was called that many times. The upper bound (maximum allowed number of calls) will be checked right away, i.e. whenever a setup gets called. (@stakx, #1319)
+* Add `ThrowsAsync` methods for non-generic `ValueTask` (@johnthcall, #1235)
 
 ## 4.18.4 (2022-12-30)
 

src/Moq/ReturnsExtensions.cs

@@ -90,6 +90,22 @@ public static partial class ReturnsExtensions
 				return tcs.Task;
 			});
 		}
+
+		/// <summary>
+		/// Specifies the exception to throw when the asynchronous method is invoked.
+		/// </summary>
+		/// <typeparam name="TMock">Mocked type.</typeparam>
+		/// <param name="mock">Returns verb which represents the mocked type and the valuetask return type</param>
+		/// <param name="exception">Exception instance to throw.</param>
+		public static IReturnsResult<TMock> ThrowsAsync<TMock>(this IReturns<TMock, ValueTask> mock, Exception exception) where TMock : class
+		{
+			return mock.Returns(() =>
+			{
+				var tcs = new TaskCompletionSource<bool>();
+				tcs.SetException(exception);
+				return new ValueTask(tcs.Task);
+			});
+		}
 
 		/// <summary>
 		/// Specifies the exception to throw when the asynchronous method is invoked.

tests/Moq.Tests/ReturnsExtensionsFixture.cs

@@ -37,6 +37,8 @@ public interface IAsyncInterface
 
 		public interface IValueTaskAsyncInterface
 		{
+			ValueTask NoParametersNonGenericValueTaskReturnType();
+
 			ValueTask<string> NoParametersRefReturnType();
 
 			ValueTask<int> NoParametersValueReturnType();
@@ -674,6 +676,20 @@ public void ValueTaskReturnsAsyncFunc_onEachInvocation_RefReturnTypeLazyEvaluati
 			Assert.NotSame(firstTask.Result, secondTask.Result);
 		}
 
+		[Fact]
+		public void ValueTaskThrowsAsync_on_NoParametersNonGenericValueTaskReturnType()
+		{
+			var mock = new Mock<IValueTaskAsyncInterface>();
+			var exception = new InvalidOperationException();
+			mock.Setup(x => x.NoParametersNonGenericValueTaskReturnType()).ThrowsAsync(exception);
+
+			var task = mock.Object.NoParametersNonGenericValueTaskReturnType();
+
+			Assert.IsType<ValueTask>(task);
+			Assert.True(task.IsFaulted);
+			Assert.Equal(exception, task.AsTask().Exception.InnerException);
+		}
+
 		[Fact]
 		public void ValueTaskThrowsAsync_on_NoParametersRefReturnType()
 		{