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POxUnit and Moq do not support async - await keywords
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  1. POxUnit and Moq do not support async - await keywords
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    copied!<p>I am trying to discover how to apply the async and await keywords to my xUnit tests. I am using xUnit 1.9 and Async CTP 1.3. Here is my test case</p> <p>I have an interface which specifies one asynchronous method call</p> <pre><code>public interface IDoStuffAsync { Task AnAsyncMethod(string value); } </code></pre> <p>I have a class which consumes the interface and calls the async method</p> <pre><code>public class UseAnAsyncThing { private readonly IDoStuffAsync _doStuffAsync; public UseAnAsyncThing(IDoStuffAsync doStuffAsync) { _doStuffAsync = doStuffAsync; } public async Task DoThatAsyncOperation(string theValue) { await _doStuffAsync.AnAsyncMethod(theValue); } } </code></pre> <p>In my tests I wish to check that the method <code>DoThatAsyncOperation</code> is calling the method with the correct value so I mock the interface and use the Moq to verify the call</p> <pre><code> [Fact] public async void The_test_will_pass_even_though_it_should_fail() { var mock = new Mock&lt;IDoStuffAsync&gt;(); var sut = new UseAnAsyncThing(mock.Object); mock.Setup(x =&gt; x.AnAsyncMethod(It.IsAny&lt;string&gt;())); await sut.DoThatAsyncOperation("test"); // This won't throw a Moq.MockExcpetion so the test appears to pass // However it does not run mock.Verify(x =&gt; x.AnAsyncMethod("fail")); } </code></pre> <p>This test is using the <code>async</code> and <code>await</code> keywords. When it runs it erroneously passes as Moq should assert that the verify fails. Any code after the call to <code>sut.DoThatAsyncOperation("test");</code> does not run</p> <pre><code> [Fact] public void This_will_work_and_assert_the_reslt() { var mock = new Mock&lt;IDoStuffAsync&gt;(); var sut = new UseAnAsyncThing(mock.Object); mock.Setup(x =&gt; x.AnAsyncMethod(It.IsAny&lt;string&gt;())); sut.DoThatAsyncOperation("test").ContinueWith(y =&gt; { }); // This won't throw a Moq.MockExcpetion so the test appears to pass // However it does not run mock.Verify(x =&gt; x.AnAsyncMethod("fail")); } </code></pre> <p>This test is setup without the await and async keywords and passes fine.</p> <p>Is this expected behavior for xUnit and Moq? </p> <hr> <p><strong>Update</strong></p> <p>Thanks for Stephen's comment I managed to fix the first test by making two changes. The test now returns a Task instead of void and the Mock also returns a Task.</p> <pre><code> [Fact] public async Task The_test_will_pass_even_though_it_should_fail() { var mock = new Mock&lt;IDoStuffAsync&gt;(); var sut = new UseAnAsyncThing(mock.Object); mock.Setup(x =&gt; x.AnAsyncMethod(It.IsAny&lt;string&gt;())).ReturnAsync(true); await sut.DoThatAsyncOperation("test"); // This now fails as it should mock.Verify(x =&gt; x.AnAsyncMethod("fail")); } </code></pre>
 

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