diff -r 514cb18945aa Lib/test/test_argparse.py
--- a/Lib/test/test_argparse.py	Fri Jul 12 20:17:00 2013 -0400
+++ b/Lib/test/test_argparse.py	Sun Jul 14 11:34:48 2013 +0800
@@ -4118,6 +4118,40 @@
     version = ''
 
 
+class TestHelpMetavarArgumentsInnerBracketSplitLines(HelpTestCase):
+    """"""
+
+    def custom_type(string):
+        return string
+
+    parser_signature = Sig(prog='PROG')
+    argument_signatures = [Sig('--a', metavar='a' * 76),
+                           Sig('--b', metavar='[innerpart]outerpart'),
+                           Sig('c', metavar='c' * 76),
+                           Sig('d', metavar='[innerpart2]outerpart2'),
+                           ]
+    argument_group_signatures = []
+    usage = '''\
+       usage: PROG [-h]
+                   [--a {0}]
+                   [--b [innerpart]outerpart]
+                   {1}
+                   [innerpart2]outerpart2
+       '''.format('a' * 76, 'c' * 76)
+    help = usage + '''\
+
+       positional arguments:
+         {0}
+         [innerpart2]outerpart2
+
+       optional arguments:
+         -h, --help            show this help message and exit
+         --a {1}
+         --b [innerpart]outerpart
+       '''.format('c' * 76, 'a' * 76)
+    version = ''
+
+
 # =====================================
 # Optional/Positional constructor tests
 # =====================================