ENH: Allow extra args to method attribute of ListeningAction.

pyface/tasks/action/listening_action.py

@@ -3,7 +3,7 @@
 
 # Enthought library imports.
 from pyface.action.api import Action
-from traits.api import Any, Str
+from traits.api import Any, Str, List, Dict
 
 # Logging.
 logger = logging.getLogger(__name__)
@@ -19,6 +19,12 @@ class ListeningAction(Action):
     # function will be called with the event.
     method = Str
 
+    # Extra arguments to method
+    args = List()
+
+    # Extra keyword arguments to method
+    kwargs = Dict()
+
     # The (extended) name of the attribute that determines whether the action is
     # enabled. By default, the action is always enabled when an object is set.
     enabled_name = Str
@@ -40,7 +46,7 @@ def perform(self, event=None):
         if self.method != '':
             method = self._get_attr(self.object, self.method)
             if method:
-                method()
+                method(*self.args, **self.kwargs)
         else:
             super(ListeningAction, self).perform(event)
 

pyface/tasks/action/test_listening_action.py

@@ -0,0 +1,90 @@
+import unittest
+from listening_action import ListeningAction
+from traits.api import HasTraits
+
+
+class TestListeningAction(unittest.TestCase):
+
+	def setUp(self):
+		""" Creates a dummy class to apply listening action to
+		"""
+		class _DummyClass(HasTraits):
+			""" Dummy class to apply ListeningAction to
+			"""
+			def __init__(self, enabled=False, visible=False):
+				self.args = []
+				self.kwargs = {}
+				self.enabled = enabled
+				self.visible = visible
+
+			def dummy_method(self, *args, **kwargs):
+				self.args.extend(args)
+				self.kwargs.update(kwargs)
+		self._class = _DummyClass
+
+	def test_method(self):
+		""" Tests whether the method attribute supports extra positional 
+		and keyword arguments.
+		"""
+		# works with additional arguments?
+		dummy_obj = self._class()
+		action = ListeningAction(object=dummy_obj, method='dummy_method',
+								args=['arg1', 'arg2'], 
+								kwargs={'arg1_pos': 0, 'arg2_pos': 1})
+		action.perform()
+		self.assertEquals(dummy_obj.args, ['arg1', 'arg2'])
+		self.assertEquals(dummy_obj.kwargs, {'arg1_pos': 0, 'arg2_pos': 1})
+
+		# works without any argument?
+		dummy_obj = self._class()
+		action = ListeningAction(object=dummy_obj, method='dummy_method')
+		action.perform()
+		self.assertEquals(dummy_obj.args, [])
+		self.assertEquals(dummy_obj.kwargs, {})
+
+		# nothing happens if the specified method doesn't exist?
+		dummy_obj = self._class()
+		action = ListeningAction(object=dummy_obj, method='other_dummy_method')
+		action.perform()
+		self.assertEquals(dummy_obj.args, [])
+		self.assertEquals(dummy_obj.kwargs, {})
+
+	def test_enabled_name(self):
+		""" Whether the action follows enabled_name attribute of object to 
+		enable/disable the action
+		"""
+		# enabled by default since enabled_name is not specified
+		dummy_obj = self._class()
+		action = ListeningAction(object=dummy_obj)
+		self.assertEquals(action.enabled, True)
+
+		# disabled since the specified enabled_name attribute is set to False
+		dummy_obj = self._class(enabled=False)
+		action = ListeningAction(object=dummy_obj, enabled_name='enabled')
+		self.assertEquals(action.enabled, False)
+
+		# what if enabled_name attribute of object is changed
+		dummy_obj.enabled = True
+		self.assertEquals(action.enabled, True)
+
+	def test_visible_name(self):
+		""" Whether the action follows visible_name attribute of object to 
+		make the action visible/invisible
+		"""
+		# enabled by default since enabled_name is not specified
+		dummy_obj = self._class()
+		action = ListeningAction(object=dummy_obj)
+		self.assertEquals(action.visible, True)
+
+		# disabled since the specified enabled_name attribute is set to False
+		dummy_obj = self._class(visible=False)
+		action = ListeningAction(object=dummy_obj, visible_name='visible')
+		self.assertEquals(action.visible, False)
+
+		# what if visible_name attribute of the object is changed
+		dummy_obj.visible = True
+		self.assertEquals(action.visible, True)
+
+
+if __name__=="__main__":
+	unittest.main()