New submission from Ezio Melotti: When a single positional argument is passed to subTest(), if the argument is false, its value won't be displayed in the output -- (<subtest>) will appear instead:
>>> import unittest >>> class NumbersTest(unittest.TestCase): ... def test_odd(self): ... for i in range(4): ... with self.subTest(i): # single positional arg ... self.assertNotEqual(i%2, 0) ... >>> unittest.main(exit=False) ====================================================================== FAIL: test_odd (__main__.NumbersTest) (<subtest>) ---------------------------------------------------------------------- Traceback (most recent call last): File "<stdin>", line 5, in test_odd AssertionError: 0 == 0 ====================================================================== FAIL: test_odd (__main__.NumbersTest) [2] ---------------------------------------------------------------------- Traceback (most recent call last): File "<stdin>", line 5, in test_odd AssertionError: 0 == 0 ---------------------------------------------------------------------- Ran 1 test in 0.001s FAILED (failures=2) This is because subTest() accepts a positional "msg" arg, passes it to _SubTest (Lib/unittest/case.py:515), and then _SubTest checks using "if self._message:" (Lib/unittest/case.py:1400). I think it would be better to check the message against a sentinel value instead. ---------- components: Library (Lib) keywords: easy messages: 254827 nosy: ezio.melotti, michael.foord, pitrou, rbcollins priority: normal severity: normal stage: test needed status: open title: Confusing output for TestCase.subTest(0) type: behavior versions: Python 3.4, Python 3.5, Python 3.6 _______________________________________ Python tracker <rep...@bugs.python.org> <http://bugs.python.org/issue25651> _______________________________________ _______________________________________________ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
