fix: suppress spurious implied-default element injection in api round-trip (#228)

src/include/mx/api/ClefData.h

@@ -41,6 +41,9 @@ class ClefData
     // int staffIndex;
     ClefSymbol symbol;
     int line;
+    // When true (the default), the writer emits <line>. Set to false when the source
+    // had no <line> element so the round-trip does not inject an implied default (#228).
+    bool isLineSpecified;
     int octaveChange;
     int tickTimePosition;
     ClefLocation location;
@@ -69,6 +72,7 @@ MXAPI_EQUALS_BEGIN(ClefData)
 // MXAPI_EQUALS_MEMBER( staffIndex )
 MXAPI_EQUALS_MEMBER(symbol)
 MXAPI_EQUALS_MEMBER(line)
+MXAPI_EQUALS_MEMBER(isLineSpecified)
 MXAPI_EQUALS_MEMBER(octaveChange)
 MXAPI_EQUALS_MEMBER(tickTimePosition)
 MXAPI_EQUALS_MEMBER(location)

src/include/mx/api/DurationData.h

@@ -66,8 +66,13 @@ struct DurationData
     DurationData();
 
     DurationName durationName; // i.e. quarter, eighth etc
-    int durationDots;          // dots
-    int durationTimeTicks;     // length of the note denominated in ticksPerQuarter
+    // When true (the default), the writer emits <type>. Set to false when the source
+    // had no <type> element so the round-trip does not inject an implied default (#228).
+    // When authoring, leave true and set durationName to control the display type;
+    // durationName and durationTimeTicks are independent (type is graphical, duration is sound).
+    bool isDurationNameSpecified;
+    int durationDots;      // dots
+    int durationTimeTicks; // length of the note denominated in ticksPerQuarter
     bool isTied; // affects sound only. is the note combined sound-wise with the following note of the same pitch
     int timeModificationActualNotes;              // i.e. for a triplet this would be 3
     int timeModificationNormalNotes;              // i.e. for a triplet this would be 2
@@ -78,6 +83,7 @@ struct DurationData
 
 MXAPI_EQUALS_BEGIN(DurationData)
 MXAPI_EQUALS_MEMBER(durationName)
+MXAPI_EQUALS_MEMBER(isDurationNameSpecified)
 MXAPI_EQUALS_MEMBER(durationDots)
 MXAPI_EQUALS_MEMBER(durationTimeTicks)
 MXAPI_EQUALS_MEMBER(isTied)

src/private/mx/api/ClefData.cpp

@@ -10,8 +10,8 @@ namespace mx
 namespace api
 {
 ClefData::ClefData()
-    : symbol{DEFAULT_CLEF_SYMBOL}, line{DEFAULT_CLEF_LINE}, octaveChange{DEFAULT_CLEF_OCTAVE_CHANGE},
-      tickTimePosition{0}, location{ClefLocation::unspecified}
+    : symbol{DEFAULT_CLEF_SYMBOL}, line{DEFAULT_CLEF_LINE}, isLineSpecified{true},
+      octaveChange{DEFAULT_CLEF_OCTAVE_CHANGE}, tickTimePosition{0}, location{ClefLocation::unspecified}
 {
 }
 

src/private/mx/api/DurationData.cpp

@@ -9,8 +9,8 @@ namespace mx
 namespace api
 {
 DurationData::DurationData()
-    : durationName{DurationName::unspecified}, durationDots{0}, durationTimeTicks{1}, isTied{false},
-      timeModificationActualNotes{1}, timeModificationNormalNotes{1},
+    : durationName{DurationName::unspecified}, isDurationNameSpecified{true}, durationDots{0}, durationTimeTicks{1},
+      isTied{false}, timeModificationActualNotes{1}, timeModificationNormalNotes{1},
       timeModificationNormalType{api::DurationName::unspecified}, timeModificationNormalTypeDots{0}
 {
 }

src/private/mx/impl/MeasureReader.cpp

@@ -759,9 +759,11 @@ void MeasureReader::importClef(const core::Clef &inClef) const
     if (inClef.clef().line().has_value())
     {
         clefData.line = inClef.clef().line()->value();
+        clefData.isLineSpecified = true;
     }
     else
     {
+        clefData.isLineSpecified = false;
         switch (clefData.symbol)
         {
         case api::ClefSymbol::g:

src/private/mx/impl/MeasureWriter.cpp

@@ -377,6 +377,7 @@ void MeasureWriter::writeStaves()
 
 void MeasureWriter::writeVoices(const api::StaffData &inStaff)
 {
+    const int numVoices = static_cast<int>(inStaff.voices.size());
     auto clefIter = inStaff.clefs.cbegin();
     const auto clefEnd = inStaff.clefs.cend();
     while (clefIter != clefEnd && clefIter->tickTimePosition == 0)
@@ -451,9 +452,13 @@ void MeasureWriter::writeVoices(const api::StaffData &inStaff)
             myPropertiesWriter->flushBuffer();
             writeDirections(directionIter, directionEnd, noteIter, std::cbegin(voice.second.notes), noteEnd);
 
-            NoteWriter writer{
-                apiNote,  myHistory.getCursor(), myScoreWriter, myPreviousCursor.isChordActive, voice.second.notes,
-                noteIndex};
+            NoteWriter writer{apiNote,
+                              myHistory.getCursor(),
+                              myScoreWriter,
+                              myPreviousCursor.isChordActive,
+                              voice.second.notes,
+                              noteIndex,
+                              numVoices};
             myOutMeasure.addMusicData(core::MusicDataChoice::note(writer.getNote(isStartOfChord)));
             myHistory.log("addNote cursorTime " + std::to_string(myHistory.getCursor().tickTimePosition) +
                           ", noteTime " + std::to_string(apiNote.tickTimePosition));

src/private/mx/impl/NoteFunctions.cpp

@@ -92,10 +92,12 @@ api::NoteData NoteFunctions::parseNote() const
     if (reader.getIsDurationTypeSpecified())
     {
         myOutNoteData.durationData.durationName = converter.convert(reader.getDurationType());
+        myOutNoteData.durationData.isDurationNameSpecified = true;
     }
     else
     {
         myOutNoteData.durationData.durationName = deriveNoteTypeFromDurationValue(reader);
+        myOutNoteData.durationData.isDurationNameSpecified = false;
     }
 
     myOutNoteData.durationData.durationDots = reader.getNumDots();

src/private/mx/impl/NoteWriter.cpp

@@ -33,10 +33,11 @@ namespace impl
 {
 NoteWriter::NoteWriter(const api::NoteData &inNoteData, const MeasureCursor &inCursor, const ScoreWriter &inScoreWriter,
                        bool isPreviousNoteAChordMember, const std::vector<mx::api::NoteData> &inSiblingNotes,
-                       int inNoteIndex)
+                       int inNoteIndex, int inNumVoices)
     : myNoteData{inNoteData}, myCursor{inCursor}, myScoreWriter{inScoreWriter}, myConverter{},
       myIsPreviousNoteAChordMember{isPreviousNoteAChordMember}, mySiblingNotes{inSiblingNotes},
-      myNoteIndex{inNoteIndex}, myOutNote{}, myOutFullNoteGroup{}, myOutTies{}, myOutTieNotationsChoices{}
+      myNoteIndex{inNoteIndex}, myNumVoices{inNumVoices}, myOutNote{}, myOutFullNoteGroup{}, myOutTies{},
+      myOutTieNotationsChoices{}
 {
 }
 
@@ -375,18 +376,21 @@ void NoteWriter::setStaffAndVoice() const
         myOutNote.setStaff(myCursor.staffIndex + 1);
     }
 
-    if (myCursor.voiceIndex >= 0)
+    const bool sourceHadVoice = myNoteData.userRequestedVoiceNumber != -1;
+    const bool isNonDefaultVoice = myCursor.voiceIndex > 0;
+    const bool isMultiVoiceStaff = myNumVoices > 1;
+    if (myCursor.voiceIndex >= 0 && (sourceHadVoice || isNonDefaultVoice || isMultiVoiceStaff))
     {
         auto editorialVoice = myOutNote.editorialVoice();
         editorialVoice.setVoice(std::to_string(myCursor.voiceIndex + 1));
         myOutNote.setEditorialVoice(std::move(editorialVoice));
     }
-    // TODO - only show voice number if it is needed i.e. only show if != 0 or voiceCount > 1
 }
 
 void NoteWriter::setDurationNameAndDots() const
 {
-    if (!myNoteData.isRest || !myNoteData.isMeasureRest)
+    const bool isMeasureRest = myNoteData.isRest && myNoteData.isMeasureRest;
+    if (myNoteData.durationData.isDurationNameSpecified && !isMeasureRest)
     {
         core::NoteType noteType;
         noteType.setValue(myConverter.convert(myNoteData.durationData.durationName));

src/private/mx/impl/NoteWriter.h

@@ -24,7 +24,8 @@ class NoteWriter
 {
   public:
     NoteWriter(const api::NoteData &inNoteData, const MeasureCursor &inCursor, const ScoreWriter &inScoreWriter,
-               bool isPreviousNoteAChordMember, const std::vector<mx::api::NoteData> &inSiblingNotes, int inNoteIndex);
+               bool isPreviousNoteAChordMember, const std::vector<mx::api::NoteData> &inSiblingNotes, int inNoteIndex,
+               int inNumVoices);
 
     core::Note getNote(bool isStartOfChord) const;
 
@@ -36,6 +37,7 @@ class NoteWriter
     const bool myIsPreviousNoteAChordMember;
     const std::vector<mx::api::NoteData> &mySiblingNotes;
     const int myNoteIndex;
+    const int myNumVoices;
     mutable core::Note myOutNote;
     mutable core::FullNoteGroup myOutFullNoteGroup;
     mutable std::vector<core::Tie> myOutTies;

src/private/mx/impl/PropertiesWriter.cpp

@@ -210,7 +210,7 @@ void PropertiesWriter::writeClef(int staffIndex, const api::ClefData &inClefData
     core::ClefGroup cg{};
     cg.setSign(converter.convert(inClefData.symbol));
 
-    if (inClefData.line >= 0)
+    if (inClefData.isLineSpecified)
     {
         cg.setLine(core::StaffLinePosition{inClefData.line});
     }

src/private/mxtest/api/roundtrip-baseline.txt

@@ -73,3 +73,23 @@ synthetic/segno.3.0.xml
 synthetic/segno.3.1.xml
 synthetic/coda.3.0.xml
 synthetic/coda.3.1.xml
+
+# Unblocked by #228: the writer no longer injects a spurious <type> element for
+# notes whose source omitted it. DurationData::isDurationNameSpecified tracks
+# presence; the writer emits <type> only when the flag is set.
+lysuite/ly41d_StaffGroups_Nested.xml
+lysuite/ly41f_StaffGroups_Overlapping.xml
+lysuite/ly45d_Repeats_Nested_Alternatives.xml
+lysuite/ly45e_Repeats_Nested_Alternatives.xml
+
+# Unblocked by #228 (add:line): the writer no longer injects a spurious <line>
+# element in <clef> when the source omitted it. ClefData::isLineSpecified tracks
+# presence; PropertiesWriter emits <line> only when the flag is set.
+lysuite/ly12a_Clefs.xml
+
+# Unblocked by #228 (add:voice): the writer no longer injects a spurious <voice>
+# element for notes whose source omitted it. NoteData::userRequestedVoiceNumber
+# (already -1 when absent) gates NoteWriter::setStaffAndVoice() voice emission.
+mjbsuite/ChordDirectionPlacement.xml
+mjbsuite/hello_timewise.xml
+synthetic/key-accidental.3.0.xml