test/test_black.py

   1 from glob import glob
   2 from pkg_resources import get_distribution, DistributionNotFound
   3 from re import match
   4 from subprocess import run
   5 from shutil import which
   6 from unittest import TestCase, skipUnless
   7
   8 black_version = 0.0
   9 try:
  10     vermatch = match("[\.\d]*", get_distribution("black").version)
  11     if vermatch is not None:
  12         black_version = float(vermatch.group())
  13 except DistributionNotFound:
  14     pass
  15
  16
  17 class BlackFormatter(TestCase):
  18     @skipUnless(black_version >= 21.1, "Do not trust earlier black versions")
  19     def test_black(self) -> None:
  20         if not which("black"):
  21             self.fail(f"black not installed.")
  22         cmd = (
  23             ["black", "--check", "--diff", "-l", "79"]
  24             + glob("gps303/**/*.py", recursive=True)
  25             + glob("test/**/*.py", recursive=True)
  26         )
  27         output = run(cmd, capture_output=True)
  28         if output.returncode == 1:
  29             self.fail(
  30                 f"black found code that needs reformatting:\n{output.stdout.decode()}"
  31             )
  32         if output.returncode != 0:
  33             self.fail(
  34                 f"black exited with code {output.returncode}:\n{output.stderr.decode()}"
  35             )