问题
We are currently converting some code that was using Assert.IsTrue()
, Assert.AreEqual()
, Assert.IsNotNull()
, etc. The basic unit test assert Library for C#
We want to use FluentAssertions, like value.Should().BeNull().
I'm stuck on a few tests using Assert.Fail()
in some locations. What should I use to efficiently replace those, since we want to do away with every single "Assert.*", and I can't find an equivalent in FluentAssertions?
Here is an example
[TestMethod, TestCategory("ImportantTest")]
public void MethodToTest_Circumstances_ExpectedResult()
{
// Arrange
var variable1 = new Type1() { Value = "hello" };
var variable2 = new Type2() { Name = "Bob" };
// Act
try
{
MethodToTest(variable1, variable2);
// This method should have thrown an exception
Assert.Fail();
}
catch (Exception ex)
{
ex.Should().BeOfType<DataException>();
ex.Message.Should().Be(Constants.DataMessageForMethod);
}
// Assert
// test that variable1 was changed by the method
variable1.Should().NotBeNull();
variable1.Value.Should().Be("Hello!");
// test that variable2 is unchanged because the method threw an exception before changing it
variable2.Should().NotBeNull();
variable2.Name.Should().Be("Bob");
}
回答1:
Restructure the test to utilize the .ShouldThrow<>
assertion extension.
[TestMethod, TestCategory("ImportantTest")]
public void MethodToTest_Circumstances_ExpectedResult() {
// Arrange
var variable1 = new Type1() { Value = "hello" };
var variable2 = new Type2() { Name = "Bob" };
// Act
Action act = () => MethodToTest(variable1, variable2);
// Assert
// This method should have thrown an exception
act.ShouldThrow<DataException>()
.WithMessage(Constants.DataMessageForMethod);
// test that variable1 was changed by the method
variable1.Should().NotBeNull();
variable1.Value.Should().Be("Hello!");
// test that variable2 is unchanged because the method threw an exception before changing it
variable2.Should().NotBeNull();
variable2.Name.Should().Be("Bob");
}
In the above example, if the expected exception is not thrown the the assertion would fail, stopping the test case.
You should review the documentation on asserting exceptions to get a better understanding of how to use the library.
回答2:
Following the example in here, he just dealt away with the Assert.Fail -- and use action and .ShouldThrow http://www.continuousimprover.com/2011/07/why-i-created-fluent-assertions-in.html
来源:https://stackoverflow.com/questions/45035649/how-to-replace-assert-fail-with-fluentassertions