[pitivi: 6/14] timeline: fix a bug in the transition detection code. Fixes #630827.

[Edward Hervey <edwardrv src gnome org>]

commit d33f08306e275c89272b70b3f25090f132c2ca4e
Author: Alessandro Decina <alessandro d gmail com>
Date:   Wed Sep 29 14:56:35 2010 +0200

    timeline: fix a bug in the transition detection code. Fixes #630827.

 pitivi/timeline/timeline.py |    8 ++++----
 tests/test_timeline.py      |   27 +++++++++++++++++++++++++++
 2 files changed, 31 insertions(+), 4 deletions(-)
---
diff --git a/pitivi/timeline/timeline.py b/pitivi/timeline/timeline.py
index be37adf..7009038 100644
--- a/pitivi/timeline/timeline.py
+++ b/pitivi/timeline/timeline.py
@@ -1150,13 +1150,13 @@ class MoveContext(EditingContext):
         self._restoreValues(self.default_originals)
 
     def _overlapsAreTransitions(self, focus, priority):
-        left_gap, right_gap = Gap.findAroundObject(focus)
+        tracks = set(o.track for o in focus.track_objects)
+        left_gap, right_gap = Gap.findAroundObject(focus, tracks=tracks)
 
         focus_end = focus.start + focus.duration
 
         # left_transition
         if left_gap.duration < 0:
-
             left_obj = left_gap.left_object
             left_end = left_obj.start + left_obj.duration
 
@@ -1172,7 +1172,8 @@ class MoveContext(EditingContext):
             #   overlap the previous and previous previous clips
 
             try:
-                prev_prev = self.timeline.getPreviousTimelineObject(left_obj)
+                prev_prev = self.timeline.getPreviousTimelineObject(left_obj,
+                        tracks=tracks)
                 if prev_prev.start + prev_prev.duration > self.focus.start:
                     return False
             except TimelineError:
@@ -1180,7 +1181,6 @@ class MoveContext(EditingContext):
 
         # right transition
         if right_gap.duration < 0:
-
             right_obj = right_gap.right_object
             right_end = right_obj.start + right_obj.duration
 
diff --git a/tests/test_timeline.py b/tests/test_timeline.py
index 1b36e01..f9ef98a 100644
--- a/tests/test_timeline.py
+++ b/tests/test_timeline.py
@@ -1304,6 +1304,33 @@ class TestContexts(TestCase):
         self.failUnlessEqual(self.track_object3.start, 10 * gst.SECOND)
         self.failUnlessEqual(self.track_object3.duration,  10 * gst.SECOND)
 
+    def testMoveContextOverlapTransition(self):
+        # start
+        # track1:  [focus  ][  t2  ]
+        # track2:  [t3 ]
+        self.track_object1.start = 0 * gst.SECOND
+        self.track_object1.duration = 10 * gst.SECOND
+        self.track_object1.priority = 1
+        self.track_object2.start = 10 * gst.SECOND
+        self.track_object2.duration = 10 * gst.SECOND
+        self.track_object2.priority = 1
+        self.track_object3.start = 0 * gst.SECOND
+        self.track_object3.duration = 10 * gst.SECOND
+        self.track_object3.priority = 1
+
+        # move to
+        # track1:  [focus[  ]t2  ]
+        # track2:  [t3 ]
+        context = MoveContext(self.timeline, self.track_object2, set([]))
+        context.editTo(gst.SECOND * 5, 1)
+        context.finish()
+        self.failUnlessEqual(self.track_object1.start, 0 * gst.SECOND)
+        self.failUnlessEqual(self.track_object1.duration,  10 * gst.SECOND)
+        self.failUnlessEqual(self.track_object2.start, 5 * gst.SECOND)
+        self.failUnlessEqual(self.track_object2.duration,  10 * gst.SECOND)
+        self.failUnlessEqual(self.track_object3.start, 0 * gst.SECOND)
+        self.failUnlessEqual(self.track_object3.duration,  10 * gst.SECOND)
+
     def testMoveContextFocusNotEarliest(self):
         #     [t2  ][focus]  [t3     ]
         self.track_object1.start = 10 * gst.SECOND