public void When_formatting_reason_arguments_it_should_ignore_culture() { // Arrange var scope = new AssertionScope(); // Act scope.BecauseOf("{0}", 1.234) .FailWith("{reason}"); // Assert scope.Invoking(e => e.Dispose()).Should().Throw <XunitException>() .WithMessage("*1.234*", "it should always use . as decimal separator"); }