Add ArgumentDefaultsHelpFormatter.

1 files changed, 16 insertions, 1 deletions

diff --git a/argparse.py b/argparse.py
index 4ae1c89..8ee556b 100644
--- a/argparse.py
+++ b/argparse.py
@@ -549,7 +549,7 @@ class HelpFormatter(object):
         if params.get('choices') is not None:

             choices_str = ', '.join([str(c) for c in params['choices']])

             params['choices'] = choices_str

-        return action.help % params

+        return self._get_help_string(action) % params

 

     def _iter_indented_subactions(self, action):

         try:

@@ -571,6 +571,9 @@ class HelpFormatter(object):
         return _textwrap.fill(text, width, initial_indent=indent,

                                            subsequent_indent=indent)

 

+    def _get_help_string(self, action):

+        return action.help

+

 

 class RawDescriptionHelpFormatter(HelpFormatter):

 

@@ -584,6 +587,18 @@ class RawTextHelpFormatter(RawDescriptionHelpFormatter):
         return text.splitlines()

 

 

+class ArgumentDefaultsHelpFormatter(HelpFormatter):

+

+    def _get_help_string(self, action):

+        help = action.help

+        if '%(default)' not in action.help:

+            if action.default is not SUPPRESS:

+                defaulting_nargs = [OPTIONAL, ZERO_OR_MORE]

+                if action.option_strings or action.nargs in defaulting_nargs:

+                    help += ' (default: %(default)s)'

+        return help

+

+

 # =====================

 # Options and Arguments

 # =====================