fix spltiting of already split notes. They didn't remember their parent block

engine/items.py

@@ -1384,6 +1384,9 @@ class Chord(Item):
             #newTicks = complDur / newparts
             note.duration = Duration.createByGuessing(Fraction(complDur, newparts))
 
+        #Cache it now, so it is correct for all copies created below
+        self.durationGroup.cacheMinimumNote()
+
         #Now we have one note with the duration the user wants to have. Make n-1 copies-
         spawnedNotes = []
         for block in self.parentBlocks: #weakrefs are not iterators and not iterable. So next() does not work and [x] does not work. for loop has to do.
@@ -1395,7 +1398,9 @@ class Chord(Item):
                     c = self.copy()
 
                 spawnedNotes.append(c)
+
                 block.data.insert(currentIndexInBlock+1, c) #add each new item after the original one.
+                c.parentBlocks.add(block)
             break #we only need one block since the data is the same in all blocks.
 
         def _undoSplit():
@@ -1408,7 +1413,6 @@ class Chord(Item):
 
             return lambda: self.split(newparts, _existingCopies = spawnedNotes)
 
-        self.durationGroup.cacheMinimumNote()
         return _undoSplit
 
     def augment(self):