I have a unit test that tests if an Exception is throw, but this Exception is only throw in Debug mode (via the [Conditional("DEBUG")] Attribute). If I run this test in Release mode, it fails. I tried to apply the same Attribute on the test but it's no taken into account.
How can I exclude a test in Release mode? Does it even make sense to run unit tests in Release mode or should I stick to Debug mode?
As for most of your question, it depends somewhat on what unit testing tool your using. However, in general what you want are preprocessor directives
//C#
#ifndef DEBUG
//Unit test
#endif
Perhaps for your situation
//C# - for NUnit
#if !DEBUG
[Ignore("This test runs only in debug")]
#endif
But as to whether to leave unit tests in the release version? I'd give a resounding NO. I'd suggest moving all your unit tests into it's own project and NOT including this in your releases.
Try this:
#if DEBUG
// here is your test
#endif