Issue #29290: Merge 3.5.

2 files changed, 18 insertions, 1 deletions

diff --git a/Lib/argparse.py b/Lib/argparse.py
index 209b4e9..b69c5ad 100644
--- a/Lib/argparse.py
+++ b/Lib/argparse.py
@@ -182,7 +182,7 @@ class HelpFormatter(object):
         self._root_section = self._Section(self, None)
         self._current_section = self._root_section
 
-        self._whitespace_matcher = _re.compile(r'\s+')
+        self._whitespace_matcher = _re.compile(r'\s+', _re.ASCII)
         self._long_break_matcher = _re.compile(r'\n\n\n+')
 
     # ===============================
diff --git a/Lib/test/test_argparse.py b/Lib/test/test_argparse.py
index bc83161..a5c4a8e 100644
--- a/Lib/test/test_argparse.py
+++ b/Lib/test/test_argparse.py
@@ -1943,6 +1943,23 @@ class TestAddSubparsers(TestCase):
               ++foo       foo help
             '''))
 
+    def test_help_non_breaking_spaces(self):
+        parser = ErrorRaisingArgumentParser(
+            prog='PROG', description='main description')
+        parser.add_argument(
+            "--non-breaking", action='store_false',
+            help='help message containing non-breaking spaces shall not '
+            'wrap\N{NO-BREAK SPACE}at non-breaking spaces')
+        self.assertEqual(parser.format_help(), textwrap.dedent('''\
+            usage: PROG [-h] [--non-breaking]
+
+            main description
+
+            optional arguments:
+              -h, --help      show this help message and exit
+              --non-breaking  help message containing non-breaking spaces shall not
+                              wrap\N{NO-BREAK SPACE}at non-breaking spaces
+        '''))
 
     def test_help_alternate_prefix_chars(self):
         parser = self._get_parser(prefix_chars='+:/')