Skip to content

Commit 013a092

Browse files
authored
gh-121151: argparse: Fix wrapping of long usage text of arguments inside a mutually exclusive groups (GH-121159)
1 parent 9e551f9 commit 013a092

File tree

3 files changed

+36
-7
lines changed

3 files changed

+36
-7
lines changed

Lib/argparse.py

+12-3
Original file line numberDiff line numberDiff line change
@@ -447,15 +447,24 @@ def _get_actions_usage_parts(self, actions, groups):
447447
parts.append(part)
448448

449449
# group mutually exclusive actions
450+
inserted_separators_indices = set()
450451
for start, end in sorted(inserts, reverse=True):
451452
group = inserts[start, end]
452453
group_parts = [item for item in parts[start:end] if item is not None]
454+
group_size = len(group_parts)
453455
if group.required:
454-
open, close = "()" if len(group_parts) > 1 else ("", "")
456+
open, close = "()" if group_size > 1 else ("", "")
455457
else:
456458
open, close = "[]"
457-
parts[start] = open + " | ".join(group_parts) + close
458-
for i in range(start + 1, end):
459+
group_parts[0] = open + group_parts[0]
460+
group_parts[-1] = group_parts[-1] + close
461+
for i, part in enumerate(group_parts[:-1], start=start):
462+
# insert a separator if not already done in a nested group
463+
if i not in inserted_separators_indices:
464+
parts[i] = part + ' |'
465+
inserted_separators_indices.add(i)
466+
parts[start + group_size - 1] = group_parts[-1]
467+
for i in range(start + group_size, end):
459468
parts[i] = None
460469

461470
# return the usage parts

Lib/test/test_argparse.py

+22-4
Original file line numberDiff line numberDiff line change
@@ -2959,12 +2959,12 @@ def get_parser(self, required=None):
29592959
]
29602960

29612961
usage_when_not_required = '''\
2962-
usage: PROG [-h] [--abcde ABCDE] [--fghij FGHIJ]
2963-
[--klmno KLMNO | --pqrst PQRST]
2962+
usage: PROG [-h] [--abcde ABCDE] [--fghij FGHIJ] [--klmno KLMNO |
2963+
--pqrst PQRST]
29642964
'''
29652965
usage_when_required = '''\
2966-
usage: PROG [-h] [--abcde ABCDE] [--fghij FGHIJ]
2967-
(--klmno KLMNO | --pqrst PQRST)
2966+
usage: PROG [-h] [--abcde ABCDE] [--fghij FGHIJ] (--klmno KLMNO |
2967+
--pqrst PQRST)
29682968
'''
29692969
help = '''\
29702970
@@ -4347,6 +4347,24 @@ def test_nested_mutex_groups(self):
43474347
''')
43484348
self.assertEqual(parser.format_usage(), usage)
43494349

4350+
def test_long_mutex_groups_wrap(self):
4351+
parser = argparse.ArgumentParser(prog='PROG')
4352+
g = parser.add_mutually_exclusive_group()
4353+
g.add_argument('--op1', metavar='MET', nargs='?')
4354+
g.add_argument('--op2', metavar=('MET1', 'MET2'), nargs='*')
4355+
g.add_argument('--op3', nargs='*')
4356+
g.add_argument('--op4', metavar=('MET1', 'MET2'), nargs='+')
4357+
g.add_argument('--op5', nargs='+')
4358+
g.add_argument('--op6', nargs=3)
4359+
g.add_argument('--op7', metavar=('MET1', 'MET2', 'MET3'), nargs=3)
4360+
4361+
usage = textwrap.dedent('''\
4362+
usage: PROG [-h] [--op1 [MET] | --op2 [MET1 [MET2 ...]] | --op3 [OP3 ...] |
4363+
--op4 MET1 [MET2 ...] | --op5 OP5 [OP5 ...] | --op6 OP6 OP6 OP6 |
4364+
--op7 MET1 MET2 MET3]
4365+
''')
4366+
self.assertEqual(parser.format_usage(), usage)
4367+
43504368

43514369
class TestHelpVariableExpansion(HelpTestCase):
43524370
"""Test that variables are expanded properly in help messages"""
Original file line numberDiff line numberDiff line change
@@ -0,0 +1,2 @@
1+
Fix wrapping of long usage text of arguments inside a mutually exclusive
2+
group in :mod:`argparse`.

0 commit comments

Comments
 (0)