From: Payton <72841140+paytonward6@users.noreply.github.com>
Date: Tue, 24 Sep 2024 14:14:35 +0000 (-0500)
Subject: gh-113008:  Correct argparse usage output for required, mutually exclusive groups... 
X-Git-Tag: v3.14.0a1~371
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=d21b0b5d36834d4d35aec3a01661597019594936;p=thirdparty%2FPython%2Fcpython.git

gh-113008:  Correct argparse usage output for required, mutually exclusive groups (GH-113085)
---

diff --git a/Lib/argparse.py b/Lib/argparse.py
index 66192fb92832..694c46db61d1 100644
--- a/Lib/argparse.py
+++ b/Lib/argparse.py
@@ -395,12 +395,12 @@ class HelpFormatter(object):
                 continue
 
             try:
-                start = actions.index(group._group_actions[0])
+                start = min(actions.index(item) for item in group._group_actions)
             except ValueError:
                 continue
             else:
                 end = start + len(group._group_actions)
-                if actions[start:end] == group._group_actions:
+                if set(actions[start:end]) == set(group._group_actions):
                     group_actions.update(group._group_actions)
                     inserts[start, end] = group
 
diff --git a/Lib/test/test_argparse.py b/Lib/test/test_argparse.py
index c6b769869409..ef05a6fefcff 100644
--- a/Lib/test/test_argparse.py
+++ b/Lib/test/test_argparse.py
@@ -2902,6 +2902,29 @@ class TestMutuallyExclusiveGroupErrors(TestCase):
               '''
         self.assertEqual(parser.format_help(), textwrap.dedent(expected))
 
+    def test_optional_order(self):
+        parser = ErrorRaisingArgumentParser(prog='PROG')
+        group = parser.add_mutually_exclusive_group(required=True)
+        group.add_argument('--foo')
+        group.add_argument('bar', nargs='?')
+        expected = '''\
+            usage: PROG [-h] (--foo FOO | bar)
+
+            positional arguments:
+              bar
+
+            options:
+              -h, --help  show this help message and exit
+              --foo FOO
+              '''
+        self.assertEqual(parser.format_help(), textwrap.dedent(expected))
+
+        parser = ErrorRaisingArgumentParser(prog='PROG')
+        group = parser.add_mutually_exclusive_group(required=True)
+        group.add_argument('bar', nargs='?')
+        group.add_argument('--foo')
+        self.assertEqual(parser.format_help(), textwrap.dedent(expected))
+
     def test_help_subparser_all_mutually_exclusive_group_members_suppressed(self):
         self.maxDiff = None
         parser = ErrorRaisingArgumentParser(prog='PROG')
diff --git a/Misc/NEWS.d/next/Library/2023-12-14-13-43-27.gh-issue-113008.jWYn8T.rst b/Misc/NEWS.d/next/Library/2023-12-14-13-43-27.gh-issue-113008.jWYn8T.rst
new file mode 100644
index 000000000000..0f2a44299717
--- /dev/null
+++ b/Misc/NEWS.d/next/Library/2023-12-14-13-43-27.gh-issue-113008.jWYn8T.rst
@@ -0,0 +1 @@
+Correct argparse usage output for required, mutually exclusive groups containing a positional argument