Move utils/booleanaction.py to utils/argparse.py

This module is going to be enhanced with additional components in later
patches in this series, so it needs a more generic name.

1 files changed, 48 insertions, 0 deletions

diff --git a/alot/utils/argparse.py b/alot/utils/argparse.py
new file mode 100644
index 00000000..968e9097
--- /dev/null
+++ b/alot/utils/argparse.py
@@ -0,0 +1,48 @@
+# encoding=utf-8
+# Copyright (C) 2011-2012  Patrick Totzke <patricktotzke@gmail.com>
+
+# This program is free software: you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation, either version 3 of the License, or
+# (at your option) any later version.
+
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+
+# You should have received a copy of the GNU General Public License
+# along with this program.  If not, see <http://www.gnu.org/licenses/>.
+
+"""Custom extensions of the argparse module."""
+
+from __future__ import absolute_import
+
+import argparse
+
+
+TRUEISH = ['true', 'yes', 'on', '1', 't', 'y']
+FALSISH = ['false', 'no', 'off', '0', 'f', 'n']
+
+
+def boolean(string):
+    string = string.lower()
+    if string in FALSISH:
+        return False
+    elif string in TRUEISH:
+        return True
+    else:
+        raise ValueError()
+
+
+class BooleanAction(argparse.Action):
+    """
+    argparse action that can be used to store boolean values
+    """
+    def __init__(self, *args, **kwargs):
+        kwargs['type'] = boolean
+        kwargs['metavar'] = 'BOOL'
+        argparse.Action.__init__(self, *args, **kwargs)
+
+    def __call__(self, parser, namespace, values, option_string=None):
+        setattr(namespace, self.dest, values)