Making voices can disrupt makeAccidentals()

[jacobtylerwalls]

Based on case reported by Igor Praznik, music21 list 3/3/20.

s = stream.Stream()
s.insert(key.Key('Gb'))
s.insert(0, note.Note('D-5'))
s.insert(0, note.Note('D-4'))
s.show()  # During export to xml, makeNotation(), makeVoices(), makeMeasures()

makeNotation() calls makeAccidentals() per Measure object, but makeAccidentals() only inspects measure.notesAndRests, which is empty in this case because the notes have been put in voices already:

music21/music21/stream/__init__.py

Line 5867 in 93bea7c

# NOTE: this may or may have sub-streams that are not being examined

Need to grab the voice objects somewhere, possibly just recursively calling makeAccidentals(), but there are going to be corner cases here with accidentals tied from previous measures. Update: I think this is only affecting the code path where measures have not been created yet. In that case, probably easier to just call makeAccidentals() before makeVoices() and makeMeasures(), since without measures to worry about, those corner cases go away.

[jacobtylerwalls]

Or, could even do this in makeVoices(), since the root of the problem is that notes are being yanked from Measure objects into Voices, something like:

if not returnObj.haveAccidentalsBeenMade():
    returnObj.makeAccidentals()

[mscuthbert]

Hmmm...it seems better to fix this in makeAccidentals or makeNotation, since I wouldn't expect makeVoices to affect accidental status. But not entirely sure.

[jacobtylerwalls]

Agreed. The patch I linked just adds recurse() in makeAccidentals.

[mscuthbert]

Fixed in #578 -- thanks!