Support unittest.subTest context manager (Python 3.4+)

Summary

Python 3.4 added the unittest.subTest() context manager. It would be wonderful if Green elevated the information from subTest() up to the top level.

I think it’s best displayed with an example.

Example

Code (taken directly from the subTest() docs):

class NumbersTest(unittest.TestCase):

    def test_even(self):
        """
        Test that numbers between 0 and 5 are all even.
        """
        for i in range(0, 6):
            with self.subTest(i=i):
                self.assertEqual(i % 2, 0)

Green’s output:

Unittest’s output:

See how the standard unittest module will show you (i=1), (i=3), and (i=5) on the fail line?

Mockup:

Here’s a mockup of how Green might look when utilizing the subTest feature:

green project -vvv

I don’t think that the subTest items need to be displayed for lower verbosity levels. I also don’t think that each failed iteration needs the Traceback (like is done with unittest) unless verbosity is set to the highest level.

[lsh-0]

thanks guys, works a treat

[CleanCut]

Resolved in 2.11.0 (just released).