MusicXML export: Make rests before making notation

music21/musicxml/m21ToXml.py

@@ -466,9 +466,29 @@ def fromGeneralObject(self, obj):
                 {3.0} <music21.bar.Barline type=final>
         >>> s[note.NotRest].first().duration
         <music21.duration.Duration 3.0>
+
+        Changed in v8 -- fills gaps with rests before calling makeNotation
+        to avoid duplicating effort with :meth:`PartExporter.fixupNotationMeasured`.
+
+        >>> v = stream.Voice(note.Note())
+        >>> m = stream.Measure([meter.TimeSignature(), v])
+        >>> GEX = musicxml.m21ToXml.GeneralObjectExporter(m)
+        >>> out = GEX.parse()  # out is bytes
+        >>> outStr = out.decode('utf-8')  # now is string
+        >>> '<note print-object="no" print-spacing="yes">' in outStr
+        True
         '''
         classes = obj.classes
         outObj = None
+
+        if isinstance(obj, stream.Stream) and self.makeNotation:
+            obj.makeRests(refStreamOrTimeRange=[0.0, obj.highestTime],
+                          fillGaps=True,
+                          inPlace=True,
+                          hideRests=True,  # just to fill up MusicXML display
+                          timeRangeFromBarDuration=True,
+                          )
+
         for cM, methName in self.classMapping.items():
             if cM in classes:
                 meth = getattr(self, methName)
@@ -1676,16 +1696,6 @@ def parsePartlikeScore(self):
         Creates a `PartExporter` for each part, and runs .parse() on that part.
         Appends the PartExporter to `self.partExporterList`
         and runs .parse() on that part. Appends the PartExporter to self.
-
-        Hide rests created at this late stage.
-
-        >>> v = stream.Voice(note.Note())
-        >>> m = stream.Measure([meter.TimeSignature(), v])
-        >>> GEX = musicxml.m21ToXml.GeneralObjectExporter(m)
-        >>> out = GEX.parse()  # out is bytes
-        >>> outStr = out.decode('utf-8')  # now is string
-        >>> '<note print-object="no" print-spacing="yes">' in outStr
-        True
         '''
         if not self.partExporterList:
             self._populatePartExporterList()
@@ -2641,16 +2651,6 @@ def parse(self):
 
         # Suppose that everything below this is a measure
         if self.makeNotation:
-            # hide any rests created at this late stage, because we are
-            # merely trying to fill up MusicXML display, not impose things on users
-            self.stream.makeRests(refStreamOrTimeRange=self.refStreamOrTimeRange,
-                                  inPlace=True,
-                                  hideRests=True,
-                                  timeRangeFromBarDuration=True,
-                                  )
-
-            # Split complex durations in place (fast if none found)
-            # Do this after makeRests since makeRests might create complex durations
             self.stream = self.stream.splitAtDurations(recurse=True)[0]
 
             if self.stream.getElementsByClass(stream.Measure):
@@ -2837,7 +2837,7 @@ def fixupNotationMeasured(self):
         them into the first measure if necessary.
 
         Checks if makeAccidentals is run, and haveBeamsBeenMade is done, and
-        remake tuplets on the assumption that makeRests() may necessitate changes.
+        tuplets have been made.
 
         Changed in v7 -- no longer accepts `measureStream` argument.
         '''
@@ -2867,20 +2867,18 @@ def fixupNotationMeasured(self):
             if outerTimeSignatures:
                 first_measure.timeSignature = outerTimeSignatures.first()
 
-        # see if accidentals/beams should be processed
+        # see if accidentals/beams/tuplets should be processed
         if not part.streamStatus.haveAccidentalsBeenMade():
             part.makeAccidentals(inPlace=True)
         if not part.streamStatus.beams:
             try:
                 part.makeBeams(inPlace=True)
             except exceptions21.StreamException as se:  # no measures or no time sig?
                 warnings.warn(MusicXMLWarning, str(se))
-        # tuplets should be processed anyway (affected by earlier makeRests)
-        # technically, beams could be affected also, but we don't want to destroy
-        # existing beam information (e.g. single-syllable vocal flags)
-        for m in measures:
-            for m_or_v in [m, *m.voices]:
-                stream.makeNotation.makeTupletBrackets(m_or_v, inPlace=True)
+        if not part.streamStatus.tuplets:
+            for m in measures:
+                for m_or_v in [m, *m.voices]:
+                    stream.makeNotation.makeTupletBrackets(m_or_v, inPlace=True)
 
         if not self.spannerBundle:
             self.spannerBundle = part.spannerBundle

music21/musicxml/test_m21ToXml.py

@@ -419,9 +419,13 @@ def testMeasurePadding(self):
         s = stream.Score([converter.parse('tinyNotation: 4/4 c4')])
         s[stream.Measure].first().paddingLeft = 2.0
         s[stream.Measure].first().paddingRight = 1.0
+        # workaround until getET() helper starts calling fromGeneralObject
+        s = GeneralObjectExporter().fromGeneralObject(s)
         tree = self.getET(s)
         self.assertEqual(len(tree.findall('.//rest')), 0)
         s[stream.Measure].first().paddingLeft = 1.0
+        # workaround until getET() helper starts calling fromGeneralObject
+        s = GeneralObjectExporter().fromGeneralObject(s)
         tree = self.getET(s)
         self.assertEqual(len(tree.findall('.//rest')), 1)
 
@@ -455,6 +459,7 @@ def testOutOfBoundsExpressionDoesNotCreateForward(self):
         m.insert(2, tempo.MetronomeMark('slow', 40))
 
         gex = GeneralObjectExporter()
+        gex.makeNotation = False
         tree = self.getET(gex.fromGeneralObject(m))
         self.assertFalse(tree.findall('.//forward'))
         self.assertEqual(
@@ -594,6 +599,7 @@ def testArpeggioMarkSpannersNonArpeggiate(self):
 
     def testExportChordSymbolsWithRealizedDurations(self):
         gex = GeneralObjectExporter()
+        gex.makeNotation = False
 
         def realizeDurationsAndAssertTags(mm: stream.Measure, forwardTag=False, offsetTag=False):
             mm = copy.deepcopy(mm)

music21/stream/makeNotation.py

@@ -840,6 +840,9 @@ def makeRests(
     else:
         returnObj = s
 
+    # Invalidate tuplet status
+    returnObj.streamStatus.tuplets = None
+
     if returnObj.iter().parts:
         for inner_part in returnObj.iter().parts:
             inner_part.makeRests(