tests/test_fixtures: set NOCOLOR=1 allowing plain assertions in pytest --help

argparse [1] enables colors by default since Python 3.14. This breaks
asserting that the help text contains
"--lg-coordinator=COORDINATOR_ADDRESS" due to escape codes and a
different output format.

Fix that by passing NO_COLOR=1 in the test's environment.

[1] https://docs.python.org/3.14/library/argparse.html#color

Signed-off-by: Bastian Krause <bst@pengutronix.de>

Author: Bastian-Krause

tests/test_fixtures.py

@@ -62,7 +62,11 @@ def test_env_with_junit(short_env, short_test, tmpdir):
         spawn.close()
         assert spawn.exitstatus == 0
 
-def test_help(short_test):
+def test_help(short_test, monkeypatch):
+    # argparse in Python >= 3.14 enables colored output by default,
+    # disable that to allow argument assertions below
+    monkeypatch.setenv("NO_COLOR", "1")
+
     with pexpect.spawn(f'pytest --help {short_test}') as spawn:
         spawn.expect(pexpect.EOF)
         assert b'--lg-coordinator=COORDINATOR_ADDRESS' in spawn.before