Hang on up/down of note tied to itself
Ubuntu 14.04, GIT commit: 2c43586
1) new score
2) note input, "7 C +" to create tied whole notes
3) exit note input mode
4) double click tie, drag end point back to first note & release when it highlights
5) exit edit mode
6) click first note
7) up or down
The code at the beginning of Selection::uniqueNotes that tries to find the beginning of the tie is in an infinite loop, because tieBack points back to itself.
Easy enough to fix here, but I wonder where else there might be similar problems?
Maybe we should simply disable creating these sorts of ties. On the other hand, I'm still wondering is it is supposed to be supported to create one-sided ties. It's a common request, it more or less is supported in the code, and it seems we used to have it exposed in the GUI. Ties to oneself could be a substitute for a true one-sided tie.
Although this is a hang, which is essentially a crash-in-waiting, I don't know that it needs to be critical, as few will encounter this unless we choose to document this as an official way to simulate one-sided ties.