feat!(pitch): 💥 use double, triple, and quadruple prime symbols for H…

…elmholtz notation (#502)

README.md

@@ -150,7 +150,7 @@ Note.d.flat
   ..toString(system: NoteNotation.german); // Des
 
 Note.b.flat.inOctave(-1).toString(); // B♭-1
-Note.c.inOctave(6).toString(system: PitchNotation.helmholtz); // c′′′
+Note.c.inOctave(6).toString(system: PitchNotation.helmholtz); // c‴
 
 PitchClass.c.toString(); // {C}
 PitchClass.dSharp.toString(); // {D♯|E♭}

example/main.dart

@@ -69,7 +69,7 @@ void main() {
     ..toString(system: NoteNotation.german); // Des
 
   Note.b.flat.inOctave(-1).toString(); // B♭-1
-  Note.c.inOctave(6).toString(system: PitchNotation.helmholtz); // c′′′
+  Note.c.inOctave(6).toString(system: PitchNotation.helmholtz); // c‴
 
   PitchClass.c.toString(); // {C}
   PitchClass.dSharp.toString(); // {D♯|E♭}

lib/src/note/pitch.dart

@@ -46,10 +46,18 @@ final class Pitch extends Scalable<Pitch> implements Comparable<Pitch> {
   static const referenceOctave = 4;
 
   static const _superPrime = '′';
+  static const _superDoublePrime = '″';
+  static const _superTriplePrime = '‴';
+  static const _superQuadruplePrime = '⁗';
   static const _superPrimeAlt = "'";
   static const _subPrime = '͵';
   static const _subPrimeAlt = ',';
 
+  static const _compoundPrimeSymbols = [
+    _superDoublePrime,
+    _superTriplePrime,
+    _superQuadruplePrime,
+  ];
   static const _primeSymbols = [
     _superPrime,
     _superPrimeAlt,
@@ -58,9 +66,15 @@ final class Pitch extends Scalable<Pitch> implements Comparable<Pitch> {
   ];
 
   static final _scientificNotationRegExp = RegExp(r'^(.+?)([-]?\d+)$');
-  static final _helmholtzNotationRegExp =
-      RegExp('(^[A-Ga-g${Accidental.symbols.join()}]+)'
-          '(${[for (final symbol in _primeSymbols) '$symbol+'].join('|')})?\$');
+  static final _helmholtzNotationRegExp = RegExp(
+    '(^(?:${[
+      for (final baseNote in BaseNote.values) baseNote.name,
+    ].join('|')})[${Accidental.symbols.join()}]*)(${[
+      ..._compoundPrimeSymbols,
+      for (final symbol in _primeSymbols) '$symbol+',
+    ].join('|')})?\$',
+    caseSensitive: false,
+  );
 
   /// Parse [source] as a [Pitch] and return its value.
   ///
@@ -92,12 +106,17 @@ final class Pitch extends Scalable<Pitch> implements Comparable<Pitch> {
           ? switch (primes?.first) {
               '' || null => middleOctave - 1,
               _subPrime || _subPrimeAlt => middleOctave - primes!.length - 1,
-              _ => throw FormatException('Invalid Pitch', source),
+              _ =>
+                throw FormatException('Invalid Pitch', source, notePart.length),
             }
           : switch (primes?.first) {
               '' || null => middleOctave,
               _superPrime || _superPrimeAlt => middleOctave + primes!.length,
-              _ => throw FormatException('Invalid Pitch', source),
+              _superDoublePrime => middleOctave + primes!.length + 1,
+              _superTriplePrime => middleOctave + primes!.length + 2,
+              _superQuadruplePrime => middleOctave + primes!.length + 3,
+              _ =>
+                throw FormatException('Invalid Pitch', source, notePart.length),
             };
 
       return Pitch(Note.parse(notePart), octave: octave);
@@ -606,12 +625,21 @@ final class HelmholtzPitchNotation extends PitchNotation {
   static const romance =
       HelmholtzPitchNotation(noteSystem: NoteNotation.romance);
 
+  static String _symbols(int n) => switch (n) {
+        4 => Pitch._superQuadruplePrime,
+        3 => Pitch._superTriplePrime,
+        2 => Pitch._superDoublePrime,
+        < 0 => Pitch._subPrime * n.abs(),
+        _ => Pitch._superPrime * n,
+      };
+
   @override
   String pitch(Pitch pitch) {
     final note = pitch.note.toString(system: noteSystem);
 
-    return pitch.octave >= 3
-        ? '${note.toLowerCase()}${Pitch._superPrime * (pitch.octave - 3)}'
-        : '$note${Pitch._subPrime * (pitch.octave - 2).abs()}';
+    return switch (pitch.octave) {
+      >= 3 => '${note.toLowerCase()}${_symbols(pitch.octave - 3)}',
+      _ => '$note${_symbols(pitch.octave - 2)}',
+    };
   }
 }

test/src/note/pitch_test.dart

@@ -8,13 +8,17 @@ void main() {
     group('.parse()', () {
       test('throws a FormatException when source is invalid', () {
         expect(() => Pitch.parse('x'), throwsFormatException);
+        expect(() => Pitch.parse('aa'), throwsFormatException);
         expect(() => Pitch.parse("A,'"), throwsFormatException);
         expect(() => Pitch.parse('bb,'), throwsFormatException);
         expect(() => Pitch.parse("F#'"), throwsFormatException);
         expect(() => Pitch.parse("g''h"), throwsFormatException);
         expect(() => Pitch.parse('C,d'), throwsFormatException);
+        expect(() => Pitch.parse("d′'"), throwsFormatException);
+        expect(() => Pitch.parse('f″″'), throwsFormatException);
 
         expect(() => Pitch.parse('D5,'), throwsFormatException);
+        expect(() => Pitch.parse('ba'), throwsFormatException);
         expect(() => Pitch.parse("d7'"), throwsFormatException);
         expect(() => Pitch.parse("e'4"), throwsFormatException);
         expect(() => Pitch.parse("'E3"), throwsFormatException);
@@ -37,7 +41,8 @@ void main() {
         expect(Pitch.parse('f'), Note.f.inOctave(3));
         expect(Pitch.parse("d#'"), Note.d.sharp.inOctave(4));
         expect(Pitch.parse("ebb''"), Note.e.flat.flat.inOctave(5));
-        expect(Pitch.parse('gx′′′'), Note.g.sharp.sharp.inOctave(6));
+        expect(Pitch.parse('b#′′'), Note.b.sharp.inOctave(5));
+        expect(Pitch.parse('gx‴'), Note.g.sharp.sharp.inOctave(6));
 
         var pitch = Note.b.flat.flat.inOctave(-2);
         expect(Pitch.parse(pitch.toString()), pitch);
@@ -1229,11 +1234,15 @@ void main() {
         );
         expect(
           Note.f.sharp.inOctave(5).toString(system: PitchNotation.helmholtz),
-          'f♯′′',
+          'f♯″',
         );
         expect(
           Note.e.inOctave(7).toString(system: PitchNotation.helmholtz),
-          'e′′′′',
+          'e⁗',
+        );
+        expect(
+          Note.b.flat.inOctave(8).toString(system: PitchNotation.helmholtz),
+          'b♭′′′′′',
         );
       });
 
@@ -1282,11 +1291,11 @@ void main() {
           Note.a.flat
               .inOctave(5)
               .toString(system: HelmholtzPitchNotation.german),
-          'as′′',
+          'as″',
         );
         expect(
           Note.e.inOctave(7).toString(system: HelmholtzPitchNotation.german),
-          'e′′′′',
+          'e⁗',
         );
       });
 
@@ -1335,11 +1344,11 @@ void main() {
           Note.a.flat
               .inOctave(5)
               .toString(system: HelmholtzPitchNotation.romance),
-          'la♭′′',
+          'la♭″',
         );
         expect(
-          Note.e.inOctave(7).toString(system: HelmholtzPitchNotation.romance),
-          'mi′′′′',
+          Note.e.inOctave(6).toString(system: HelmholtzPitchNotation.romance),
+          'mi‴',
         );
       });