[Python-checkins] cpython (merge 3.4 -> default): Merge: #9351: set_defaults on subparser is no longer ignored if set on parent.

[r.david.murray]

https://hg.python.org/cpython/rev/b35a811d4420
changeset: 93121:b35a811d4420
parent: 93119:5beb1ea76f36
parent: 93120:e9cb45ccf42b
user: R David Murray <rdmurray at bitdance.com>
date: Fri Oct 17 19:58:03 2014 -0400
summary:
Merge: #9351: set_defaults on subparser is no longer ignored if set on parent.

files:
Lib/argparse.py | 9 ++++++++-
Lib/test/test_argparse.py | 7 +++++++
Misc/NEWS | 3 +++
3 files changed, 18 insertions(+), 1 deletions(-)


diff --git a/Lib/argparse.py b/Lib/argparse.py
--- a/Lib/argparse.py
+++ b/Lib/argparse.py
@@ -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 --git a/Lib/test/test_argparse.py b/Lib/test/test_argparse.py
--- a/Lib/test/test_argparse.py
+++ b/Lib/test/test_argparse.py
@@ -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 --git a/Misc/NEWS b/Misc/NEWS
--- a/Misc/NEWS
+++ b/Misc/NEWS
@@ -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.