diff --git a/Doc/library/argparse.rst b/Doc/library/argparse.rst index 60411b0a0c9748..5058290878d358 100644 --- a/Doc/library/argparse.rst +++ b/Doc/library/argparse.rst @@ -137,6 +137,9 @@ ArgumentParser objects .. versionchanged:: 3.15 *suggest_on_error* default changed to ``True``. + .. versionchanged:: next + :class:`~argparse.ArgumentParser` objects are now :mod:`pickleable `. + The following sections describe how each of these are used. diff --git a/Lib/argparse.py b/Lib/argparse.py index 0494b545f2f1d3..296a210ad832da 100644 --- a/Lib/argparse.py +++ b/Lib/argparse.py @@ -148,6 +148,10 @@ def _copy_items(items): return copy.copy(items) +def _identity(value): + return value + + # =============== # Formatting Help # =============== @@ -199,7 +203,7 @@ def _set_color(self, color, *, file=None): self._decolor = decolor else: self._theme = get_theme(force_no_color=True).argparse - self._decolor = lambda text: text + self._decolor = _identity # =============================== # Section and indentation methods @@ -1981,9 +1985,7 @@ def __init__(self, self._subparsers = None # register types - def identity(string): - return string - self.register('type', None, identity) + self.register('type', None, _identity) # add help argument if necessary # (using explicit default to override global argument_default) diff --git a/Lib/test/test_argparse.py b/Lib/test/test_argparse.py index 78f02f70b9f0fc..4526efe4b80ef4 100644 --- a/Lib/test/test_argparse.py +++ b/Lib/test/test_argparse.py @@ -80,6 +80,27 @@ def test_skip_invalid_stdout(self): self.assertRegex(mocked_stderr.getvalue(), r'usage:') +class TestArgumentParserPickleable(unittest.TestCase): + + @force_not_colorized + def test_pickle_roundtrip(self): + import pickle + parser = argparse.ArgumentParser(exit_on_error=False) + parser.add_argument('--foo', type=int, default=42) + parser.add_argument('bar', nargs='?', default='baz') + for proto in range(pickle.HIGHEST_PROTOCOL + 1): + with self.subTest(protocol=proto): + # Try to pickle and unpickle the parser + parser2 = pickle.loads(pickle.dumps(parser, protocol=proto)) + # Check that the round-tripped parser still works + ns = parser2.parse_args(['--foo', '123', 'quux']) + self.assertEqual(ns.foo, 123) + self.assertEqual(ns.bar, 'quux') + ns2 = parser2.parse_args([]) + self.assertEqual(ns2.foo, 42) + self.assertEqual(ns2.bar, 'baz') + + class TestCase(unittest.TestCase): def setUp(self): diff --git a/Misc/NEWS.d/next/Library/2026-02-13-14-20-10.gh-issue-144782.0Y8TKj.rst b/Misc/NEWS.d/next/Library/2026-02-13-14-20-10.gh-issue-144782.0Y8TKj.rst new file mode 100644 index 00000000000000..95f047474b7ee9 --- /dev/null +++ b/Misc/NEWS.d/next/Library/2026-02-13-14-20-10.gh-issue-144782.0Y8TKj.rst @@ -0,0 +1 @@ +Make :class:`argparse.ArgumentParser` :mod:`pickleable `.