Filtering on individual tests

[Tillaert]

I am always frustrated that I cannot filter on individual tests, in components, projects and bases. I alwasy have to run the entire test suite.

As a solution I would like to have filter options such as --fail-fast and --focus

I have considered using the REPL, but:

• It is basically using a debugger, and we had many instances where a test passed in a REPL, but not in the pipe line, of was not even executed in the pipeline.
• Using Debuggers for development is considered an anti-pattern. It should only be used for diagnosing. Mutating the state of the system under test yields unrelyble results.

[tengstrand]

I think the right way to go is to support tagging of tests in combination with with, see how the external test runner handles this.

Then we can do things like poly test with:slow to run the slow tests.