How to test for exceptions thrown using xUnit, SubSpec and FakeItEasy
I've not heard of FakeItEasy or SubSpec (your tests look pretty funky, so I might check these out :)). However, I do use xUnit so this may be helpful:
I use Record.Exception with Assert.ThrowsDelegate
So something like:
[Fact]
public void Test()
{
// Arange
// Act
Exception ex = Record.Exception(new Assert.ThrowsDelegate(() => { service.DoStuff(); }));
// Assert
Assert.IsType(typeof(<whatever exception type you are looking for>), ex);
Assert.Equal("<whatever message text you are looking for>", ex.Message);
}
Hope that helps.
I would do it like this:
"Given a Options presenter"
.Context(() =>
presenter = new OptionsPresenter(view,
(IOptionsModel)null,
service));
"with the Save method called to save the option values"
.Do(() =>
exception = Record.Exception(() => presenter.Save()));
"expect an ValidationException to be thrown"
.Observation(() =>
Assert.IsType<ValidationException>(exception)
);
"expect an service.SaveOptions method not to be called"
.Observation(() =>
A.CallTo(() => service.SaveOptions(A<IOptionsModel>.Ignored)).MustNotHaveHappened()
);
Or better still, switching SubSpec for xBehave.net and introducing FluentAssertions:-
"Given an options presenter"
.x(() => presenter = new OptionsPresenter(view, (IOptionsModel)null, service));
"When saving the options presenter"
.x(() => exception = Record.Exception(() => presenter.Save()));
"Then a validation exception is thrown"
.x(() => exception.Should().BeOfType<ValiationException>());
"And the options model must not be saved"
.x(() => A.CallTo(() =>
service.SaveOptions(A<IOptionsModel>.Ignored)).MustNotHaveHappened());