Found out how to reproduce this.

If the start trim handle of a timeline clip is dragged to meet the end trim handle, they will get "glued" together (it looks like the start handle jumps to the right-hand side of the end handle).

After that, trying to drag the handle on the left-hand side does nothing -- it's stuck there.

Trying to drag the handle on the right-hand side left gives the traceback in the attachment.

Continuing to drag it gives this traceback:

Traceback (most recent call last):

+ Trace 218136

followed by these two when the drag operation finished:

Traceback (most recent call last):
  File "pitivi/ui/controller.py", line 140, in button_release_event
    self._drag_end(item, self._dragging, event)
  File "pitivi/ui/controller.py", line 181, in _drag_end
    self.drag_end(item, target, event)
  File "pitivi/ui/trackobject.py", line 119, in drag_end
    self._context.finish()
AttributeError: 'NoneType' object has no attribute 'finish'
Traceback (most recent call last):
  File "pitivi/ui/controller.py", line 140, in button_release_event
    self._drag_end(item, self._dragging, event)
  File "pitivi/ui/controller.py", line 183, in _drag_end
    if self._ptr_within and self._drag_threshold():
  File "pitivi/ui/controller.py", line 195, in _drag_threshold
    last = self.pos(self._dragging)
  File "pitivi/ui/controller.py", line 81, in pos
    bounds = item.get_bounds()
AttributeError: 'NoneType' object has no attribute 'get_bounds'

This workaround fixes the traceback. It doesn't fix the fundamental problem that we don't enforce a minimum length for clips in the timeline though.


diff --git a/pitivi/timeline/timeline.py b/pitivi/timeline/timeline.py
index cf6761e..f431536 100644
--- a/pitivi/timeline/timeline.py
+++ b/pitivi/timeline/timeline.py
@@ -1249,7 +1249,7 @@ class TrimStartContext(EditingContext):
         self.default_originals = self._saveValues([focus_timeline_object])
 
         ripple = self.timeline.getObjsBeforeTime(focus.start)
-        assert not focus.timeline_object in ripple
+        assert not focus.timeline_object in ripple or focus.duration == 0
         self.ripple_originals = self._saveValues(ripple)
         self.ripple_offsets = self._getOffsets(focus.start, focus.priority,
             ripple)
diff --git a/pitivi/ui/trackobject.py b/pitivi/ui/trackobject.py
index fd4e53c..3420a7c 100644
--- a/pitivi/ui/trackobject.py
+++ b/pitivi/ui/trackobject.py
@@ -398,6 +398,9 @@ class TrackObject(View, goocanvas.Group, Zoomable):
         y = (self.height + LAYER_SPACING) * self.element.priority
         self.set_simple_transform(x, y, 1, 0)
         width = self.nsToPixel(self.element.duration)
+        min_width = self.start_handle.props.width * 2
+        if width < min_width:
+            width = min_width
         w = width - self.end_handle.props.width
         self.name.props.clip_path = "M%g,%g h%g v%g h-%g z" % (
             0, 0, w, self.height, w)

commit ffdc5c39f6c9b5b7b41b6f31ed10a8a5a9a9e652
Author: Brandon Lewis <brandon_lewis@alum.berkeley.edu>
Date:   Thu Oct 29 15:10:22 2009 -0700

    timeline.py,ui.trackobject.py: check in alessandro's fix for 597703