[pitivi] undo: Reuse the effects cached in Effect*Action

[Alexandru Băluț <alexbalut src gnome org>]

commit 7bc60453390ee85b02ee0a93bd10d656632de69b
Author: Alexandru Băluț <alexandru balut gmail com>
Date:   Wed Oct 5 02:27:17 2016 +0200

    undo: Reuse the effects cached in Effect*Action
    
    No need to recreate the effects. Keep everything in memory.
    This way the TrackElementPropertyChanged objects will affect the proper
    track element (effect) when redone.
    
    Fixes https://phabricator.freedesktop.org/T7571
    
    Reviewed-by: Thibault Saunier <tsaunier gnome org>
    Differential Revision: https://phabricator.freedesktop.org/D1349

 pitivi/undo/timeline.py     |    4 +---
 tests/test_undo_timeline.py |   20 ++++++++++++++++++--
 2 files changed, 19 insertions(+), 5 deletions(-)
---
diff --git a/pitivi/undo/timeline.py b/pitivi/undo/timeline.py
index 747789b..ba6e743 100644
--- a/pitivi/undo/timeline.py
+++ b/pitivi/undo/timeline.py
@@ -130,7 +130,6 @@ class TrackElementAction(UndoableAction):
         UndoableAction.__init__(self)
         self.clip = clip
         self.track_element = track_element
-        self.asset = track_element.get_asset()
         self.track_element_props = []
         for prop in self.track_element.list_children_properties():
             if not prop.flags & GObject.PARAM_WRITABLE or \
@@ -142,13 +141,12 @@ class TrackElementAction(UndoableAction):
             self.track_element_props.append((prop_name, value))
 
     def add(self):
-        self.track_element = self.clip.add_asset(self.asset)
+        assert self.clip.add(self.track_element)
         for prop_name, prop_value in self.track_element_props:
             self.track_element.set_child_property(prop_name, prop_value)
 
     def remove(self):
         self.clip.remove(self.track_element)
-        self.track_element = None
 
 
 class EffectAddedAction(TrackElementAction):
diff --git a/tests/test_undo_timeline.py b/tests/test_undo_timeline.py
index 57229b8..91e41c2 100644
--- a/tests/test_undo_timeline.py
+++ b/tests/test_undo_timeline.py
@@ -583,7 +583,7 @@ class TestTimelineElementObserver(BaseTestUndoTimeline):
         self.action_log.redo()
         self.assertEqual(source.get_child_property("text")[1], "pigs fly!")
 
-    def testChangeEffectProperty(self):
+    def test_add_effect_change_property(self):
         stacks = []
         self.action_log.connect("commit", BaseTestUndoTimeline.commit_cb, stacks)
 
@@ -607,17 +607,33 @@ class TestTimelineElementObserver(BaseTestUndoTimeline):
 
         with self.action_log.started("change child property"):
             effect1.set_child_property("scratch-lines", 0)
-
         self.assertEqual(effect1.get_child_property("scratch-lines")[1], 0)
+
+        # Undo effect property change.
         self.action_log.undo()
         self.assertEqual(effect1.get_child_property("scratch-lines")[1], 7)
+
+        # Redo effect property change.
         self.action_log.redo()
         self.assertEqual(effect1.get_child_property("scratch-lines")[1], 0)
+
+        # Undo effect property change.
         self.action_log.undo()
         self.assertTrue(effect1 in clip1.get_children(True))
+
+        # Undo effect add.
         self.action_log.undo()
         self.assertFalse(effect1 in clip1.get_children(True))
 
+        # Redo effect add.
+        self.action_log.redo()
+        self.assertTrue(effect1 in clip1.get_children(True))
+        self.assertEqual(effect1.get_child_property("scratch-lines")[1], 7)
+
+        # Redo effect property change.
+        self.action_log.redo()
+        self.assertEqual(effect1.get_child_property("scratch-lines")[1], 0)
+
 
 class TestGObjectObserver(BaseTestUndoTimeline):