NUnit3: Assert.Throws with async Task

c# asynchronous nunit nunit-3.0
tikinoa picture tikinoa · Nov 19, 2014 · Viewed 12.9k times · Source

I am trying to port a test to NUnit3 and am getting a System.ArgumentException : 'async void' methods are not supported, please use 'async Task' instead.

[Test]
public void InvalidUsername()
{
...
var exception = Assert.Throws<HttpResponseException>(async () => await client.LoginAsync("[email protected]", testpassword));
exception.HttpResponseMessage.StatusCode.ShouldEqual(HttpStatusCode.BadRequest); // according to http://tools.ietf.org/html/rfc6749#section-5.2
...
}

Assert.Throws appears to take a TestDelegate, defined as:

public delegate void TestDelegate();

hence the ArgumentException. What is the best way to port this code?

Answer

Zabbu picture Zabbu · Mar 18, 2016

This was resolved by Nunit. You can now use Assert.ThrowsAsync<>()

https://github.com/nunit/nunit/issues/1190

Example:

Assert.ThrowsAsync<Exception>(() => YourAsyncMethod());

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