changeset:   78229:ac53876d1cc8
branch:      3.2
parent:      78226:e7f205ce080e
user:        R David Murray <rdmurray@bitdance.com>
date:        Sat Jul 21 22:20:11 2012 -0400
files:       Lib/argparse.py Lib/test/test_argparse.py Misc/NEWS
description:
#12353: argparse now correctly handles null argument values.

Patch by Torsten Landschoff.


diff -r e7f205ce080e -r ac53876d1cc8 Lib/argparse.py
--- a/Lib/argparse.py	Sat Jul 21 17:04:25 2012 -0400
+++ b/Lib/argparse.py	Sat Jul 21 22:20:11 2012 -0400
@@ -1976,7 +1976,7 @@
         for arg_string in arg_strings:
 
             # for regular arguments, just add them back into the list
-            if arg_string[0] not in self.fromfile_prefix_chars:
+            if not arg_string or arg_string[0] not in self.fromfile_prefix_chars:
                 new_arg_strings.append(arg_string)
 
             # replace arguments referencing files with the file content
diff -r e7f205ce080e -r ac53876d1cc8 Lib/test/test_argparse.py
--- a/Lib/test/test_argparse.py	Sat Jul 21 17:04:25 2012 -0400
+++ b/Lib/test/test_argparse.py	Sat Jul 21 22:20:11 2012 -0400
@@ -1371,6 +1371,7 @@
         ('X @hello', NS(a=None, x='X', y=['hello world!'])),
         ('-a B @recursive Y Z', NS(a='A', x='hello world!', y=['Y', 'Z'])),
         ('X @recursive Z -a B', NS(a='B', x='X', y=['hello world!', 'Z'])),
+        (["-a", "", "X", "Y"], NS(a='', x='X', y=['Y'])),
     ]
 
 
diff -r e7f205ce080e -r ac53876d1cc8 Misc/NEWS
--- a/Misc/NEWS	Sat Jul 21 17:04:25 2012 -0400
+++ b/Misc/NEWS	Sat Jul 21 22:20:11 2012 -0400
@@ -98,6 +98,8 @@
 Library
 -------
 
+- Issue #12353: argparse now correctly handles null argument values.
+
 - Issues #10017 and #14998: Fix TypeError using pprint on dictionaries with
   user-defined types as keys or other unorderable keys.