[hugovk]

Use the existing _colorize module already used for tracebacks and doctest so output can be controlled with the PYTHON_COLORS, NO_COLOR and FORCE_COLOR environment variables.

This PR does a couple of things to add colour:

• Enable colour for tracebacks by passing in colorize to msgLines = list(tb_e.format(colorize=can_colorize()))
• Add colour for pass/fail/errors, using pytest as a guide
• Plus some unrelated tidy-up (use more specific test methods, new-style objects, underscore variables)

Tested with some small demo scripts:

No tests ran

run-unittests-none.py

import unittest

if __name__ == "__main__":
    unittest.main()

Before	After	pytest

Passed

run-unittests-pass.py

Mode	Before	After	pytest
Regular
Verbose

Failing

run-unittests.py

import unittest


class TestThings(unittest.TestCase):
    def test_pass(self):
        self.assertTrue(True)

    def test_fail(self):
        self.assertTrue(False)

    def test_error(self):
        raise Exception("Manually raised exception")

    def test_pass2(self):
        self.assertEqual(1, 1)

    @unittest.skip("demonstrating skipping")
    def test_skip(self):
        self.fail("shouldn't happen")


class ExpectedFailureTestCase(unittest.TestCase):
    @unittest.expectedFailure
    def test_fail(self):
        self.assertEqual(1, 0, "broken")

    @unittest.expectedFailure
    def test_pass(self):
        self.assertEqual(1, 1, "not broken")


if __name__ == "__main__":
    unittest.main()

Mode	Before	After	pytest
Regular
Verbose

Subtests

run-unittests-subtests.py

import unittest


class DoSubTest(unittest.TestCase):
    def test_subtest(self):
        """Test with subtest"""
        for i in range(0, 4):
            with self.subTest(i=i):
                if i == 2:
                    raise Exception("Manually raised exception")
                self.assertEqual(i % 2, 0)


if __name__ == "__main__":
    unittest.main()

Mode	Before	After	pytest
Regular
Verbose

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📚 Documentation preview 📚: https://cpython-previews--127223.org.readthedocs.build/

• Issue: Add colour to unittest output #127221