I'm using FluentAssertions with NUnit and I realize that the method Throw() and other related methods is not listed for me to use. Do I have to install any other package to have access to this method?
I'm using the last release, 5.4.2, installed by NuGet.
The documentation doesn't make it very clear, but Should().Throw() has to be applied to an Action (or, as pointed out by @ArturKrajewski in a comment below, a Func and also async calls):
Action test = () => throw new InvalidOperationException();
test.Should().Throw<InvalidOperationException>();
So the tests could look like this:
public class AssertThrows_ExampleTests {
[Test]
public void Should_Throw_Action() {
var classToTest = new TestClass();
// Action for sync call
Action action = () => classToTest.MethodToTest();
action.Should().Throw<InvalidOperationException>();
}
[Test]
public void Should_Throw_Action_Async() {
var classToTest = new TestClass();
// Func<Task> required here for async call
Func<Task> func = async () => await classToTest.MethodToTestAsync();
func.Should().Throw<InvalidOperationException>();
}
private class TestClass {
public void MethodToTest() {
throw new InvalidOperationException();
}
public async Task MethodToTestAsync() {
throw new InvalidOperationException();
}
}
}
Or - in Fluent Assertions 5 or later - like this:
[Test]
public async Task Should_Throw_Async() {
var classToTest = new TestClass();
var test = async () => await classToTest.MethodToTestAsync();
await test.Should().ThrowAsync<InvalidOperationException>();
}
