1 files changed, 15 insertions, 1 deletions
diff --git a/alot/utils/argparse.py b/alot/utils/argparse.py
index b8e3d87d..f58b7a75 100644
--- a/alot/utils/argparse.py
+++ b/alot/utils/argparse.py
@@ -116,7 +116,7 @@ class BooleanAction(argparse.Action):
         setattr(namespace, self.dest, values)
 
 
-class ValidatedStoreAction(argparse.Action):
+class _ValidatedAction(argparse.Action):
     """An action that allows a validation function to be specificied.
 
     The validator keyword must be a function taking exactly one argument, that
@@ -128,6 +128,9 @@ class ValidatedStoreAction(argparse.Action):
         super().__init__(option_strings, dest, **kwargs)
         self.validator = validator
 
+    def _do_action(self, namespace, values):
+        raise NotImplementedError
+
     def __call__(self, parser, namespace, values, option_string=None):
         if self.validator:
             try:
@@ -135,4 +138,15 @@ class ValidatedStoreAction(argparse.Action):
             except ValidationFailed as e:
                 raise argparse.ArgumentError(self, str(e))
 
+        self._do_action(namespace, values)
+
+class ValidatedStoreAction(_ValidatedAction):
+    def _do_action(self, namespace, values):
         setattr(namespace, self.dest, values)
+class ValidatedAppendAction(_ValidatedAction):
+    def _do_action(self, namespace, values):
+        items = getattr(namespace, self.dest)
+        if items is None:
+            items = []
+        items.append(values)
+        setattr(namespace, self.dest, items)