changeset:   93121:b35a811d4420
parent:      93119:5beb1ea76f36
parent:      93120:e9cb45ccf42b
user:        R David Murray <rdmurray@bitdance.com>
date:        Fri Oct 17 19:58:03 2014 -0400
files:       Lib/test/test_argparse.py Misc/NEWS
description:
Merge: #9351: set_defaults on subparser is no longer ignored if set on parent.


diff -r 5beb1ea76f36 -r b35a811d4420 Lib/argparse.py
--- a/Lib/argparse.py	Fri Oct 17 19:32:08 2014 -0400
+++ b/Lib/argparse.py	Fri Oct 17 19:58:03 2014 -0400
@@ -1122,7 +1122,14 @@
         # parse all the remaining options into the namespace
         # store any unrecognized options on the object, so that the top
         # level parser can decide what to do with them
-        namespace, arg_strings = parser.parse_known_args(arg_strings, namespace)
+
+        # In case this subparser defines new defaults, we parse them
+        # in a new namespace object and then update the original
+        # namespace for the relevant parts.
+        subnamespace, arg_strings = parser.parse_known_args(arg_strings, None)
+        for key, value in vars(subnamespace).items():
+            setattr(namespace, key, value)
+
         if arg_strings:
             vars(namespace).setdefault(_UNRECOGNIZED_ARGS_ATTR, [])
             getattr(namespace, _UNRECOGNIZED_ARGS_ATTR).extend(arg_strings)
diff -r 5beb1ea76f36 -r b35a811d4420 Lib/test/test_argparse.py
--- a/Lib/test/test_argparse.py	Fri Oct 17 19:32:08 2014 -0400
+++ b/Lib/test/test_argparse.py	Fri Oct 17 19:58:03 2014 -0400
@@ -2781,6 +2781,13 @@
         parser = ErrorRaisingArgumentParser(parents=[parent])
         self.assertEqual(NS(x='foo'), parser.parse_args([]))
 
+    def test_set_defaults_on_parent_and_subparser(self):
+        parser = argparse.ArgumentParser()
+        xparser = parser.add_subparsers().add_parser('X')
+        parser.set_defaults(foo=1)
+        xparser.set_defaults(foo=2)
+        self.assertEqual(NS(foo=2), parser.parse_args(['X']))
+
     def test_set_defaults_same_as_add_argument(self):
         parser = ErrorRaisingArgumentParser()
         parser.set_defaults(w='W', x='X', y='Y', z='Z')
diff -r 5beb1ea76f36 -r b35a811d4420 Misc/NEWS
--- a/Misc/NEWS	Fri Oct 17 19:32:08 2014 -0400
+++ b/Misc/NEWS	Fri Oct 17 19:58:03 2014 -0400
@@ -181,6 +181,9 @@
 Library
 -------
 
+- Issue #9351: Defaults set with set_defaults on an argparse subparser
+  are no longer ignored when also set on the parent parser.
+
 - Issue #21991: Make email.headerregistry's header 'params' attributes
   be read-only (MappingProxyType).  Previously the dictionary was modifiable
   but a new one was created on each access of the attribute.