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Version: v2.0

Result Assertion Patterns

Use fluent assertions to make success/failure expectations obvious.

Success Assertions​

[Fact]
public void Parse_ValidValue_ReturnsSuccess()
{
    var result = Parse("42");

    result.ShouldBe()
        .Success()
        .Where(value => value == 42);
}

Failure Assertions​

[Fact]
public void Parse_InvalidValue_ReturnsValidationFailure()
{
    var result = Parse("abc");

    result.ShouldBe()
        .Failure()
        .WhichIs<ValidationFailure>()
        .And(failure => Assert.Contains("integer", failure.Message));
}

Pattern Tips​

  • Use WhichIs<TFailure>() to assert failure type explicitly.
  • Use And(...) for focused assertions on failure details.
  • Keep one behavior assertion per test.

See Also​