feat(mode)!: rewrite Mode enums (#78)

lib/music_notes.dart

@@ -26,6 +26,6 @@ part 'src/note/notes.dart';
 part 'src/note/positioned_note.dart';
 part 'src/scale/scale.dart';
 part 'src/tonality/key_signature.dart';
-part 'src/tonality/modes.dart';
+part 'src/tonality/mode.dart';
 part 'src/tonality/tonality.dart';
 part 'src/transposable.dart';

lib/src/note/note.dart

@@ -30,16 +30,17 @@ class Note implements MusicItem, Transposable<Note> {
   ///
   /// Example:
   /// ```dart
-  /// Note.fromTonalityAccidentals(2, Modes.major, Accidental.sharp) == Note.d
-  /// Note.fromTonalityAccidentals(0, Modes.minor) == Note.a
+  /// Note.fromTonalityAccidentals(2, TonalMode.major, Accidental.sharp)
+  ///   == Note.d
+  /// Note.fromTonalityAccidentals(0, TonalMode.minor) == Note.a
   /// ```
   factory Note.fromTonalityAccidentals(
     int accidentals,
-    Modes mode, [
+    TonalMode mode, [
     Accidental accidental = Accidental.natural,
   ]) {
     final note = Note.fromRawAccidentals(accidentals, accidental);
-    if (mode == Modes.major) return note;
+    if (mode == TonalMode.major) return note;
 
     return EnharmonicNote(note.semitones)
         .transposeBy(-Interval.minorThird)

lib/src/tonality/key_signature.dart

@@ -39,9 +39,9 @@ class KeySignature implements Comparable<KeySignature> {
   /// }
   /// ```
   Set<Tonality> get tonalities => {
-        Tonality.fromAccidentals(accidentals, Modes.major, accidental),
+        Tonality.fromAccidentals(accidentals, TonalMode.major, accidental),
         // TODO(albertms10): use `Tonality.relative`.
-        Tonality.fromAccidentals(accidentals, Modes.minor, accidental),
+        Tonality.fromAccidentals(accidentals, TonalMode.minor, accidental),
       };
 
   @override

lib/src/tonality/mode.dart

@@ -0,0 +1,58 @@
+part of '../../music_notes.dart';
+
+abstract class Mode implements Enum, Comparable<Mode> {
+  Scale get scale;
+  int get brightness;
+
+  static int compareModes(Mode a, Mode b) => compareMultiple([
+        () => a.brightness.compareTo(b.brightness),
+        () => a.name.compareTo(b.name),
+      ]);
+}
+
+enum TonalMode implements Mode {
+  major(Scale.major, brightness: 0),
+  minor(Scale.naturalMinor, brightness: -3);
+
+  @override
+  final Scale scale;
+
+  @override
+  final int brightness;
+
+  const TonalMode(this.scale, {required this.brightness});
+
+  /// Returns the inverted of this [TonalMode].
+  ///
+  /// Example:
+  /// ```dart
+  /// TonalMode.major.inverted == TonalMode.minor
+  /// TonalMode.minor.inverted == TonalMode.major
+  /// ```
+  TonalMode get opposite =>
+      this == TonalMode.major ? TonalMode.minor : TonalMode.major;
+
+  @override
+  int compareTo(Mode other) => Mode.compareModes(this, other);
+}
+
+enum ModalMode implements Mode {
+  lydian(Scale.lydian, brightness: 1),
+  ionian(Scale.ionian, brightness: 0),
+  mixolydian(Scale.mixolydian, brightness: -1),
+  dorian(Scale.dorian, brightness: -2),
+  aeolian(Scale.aeolian, brightness: -3),
+  phrygian(Scale.phrygian, brightness: -4),
+  locrian(Scale.locrian, brightness: -5);
+
+  @override
+  final Scale scale;
+
+  @override
+  final int brightness;
+
+  const ModalMode(this.scale, {required this.brightness});
+
+  @override
+  int compareTo(Mode other) => Mode.compareModes(this, other);
+}

lib/src/tonality/tonality.dart

@@ -3,62 +3,62 @@ part of '../../music_notes.dart';
 @immutable
 class Tonality implements Comparable<Tonality> {
   final Note note;
-  final Modes mode;
+  final TonalMode mode;
 
   const Tonality(this.note, this.mode);
 
-  static const cMajor = Tonality(Note.c, Modes.major);
-  static const cMinor = Tonality(Note.c, Modes.minor);
+  static const cMajor = Tonality(Note.c, TonalMode.major);
+  static const cMinor = Tonality(Note.c, TonalMode.minor);
 
-  static const cSharpMajor = Tonality(Note.cSharp, Modes.major);
-  static const cSharpMinor = Tonality(Note.cSharp, Modes.minor);
-  static const dFlatMajor = Tonality(Note.dFlat, Modes.major);
+  static const cSharpMajor = Tonality(Note.cSharp, TonalMode.major);
+  static const cSharpMinor = Tonality(Note.cSharp, TonalMode.minor);
+  static const dFlatMajor = Tonality(Note.dFlat, TonalMode.major);
 
-  static const dMajor = Tonality(Note.d, Modes.major);
-  static const dMinor = Tonality(Note.d, Modes.minor);
+  static const dMajor = Tonality(Note.d, TonalMode.major);
+  static const dMinor = Tonality(Note.d, TonalMode.minor);
 
-  static const dSharpMinor = Tonality(Note.dSharp, Modes.minor);
-  static const eFlatMajor = Tonality(Note.eFlat, Modes.major);
-  static const eFlatMinor = Tonality(Note.eFlat, Modes.minor);
+  static const dSharpMinor = Tonality(Note.dSharp, TonalMode.minor);
+  static const eFlatMajor = Tonality(Note.eFlat, TonalMode.major);
+  static const eFlatMinor = Tonality(Note.eFlat, TonalMode.minor);
 
-  static const eMajor = Tonality(Note.e, Modes.major);
-  static const eMinor = Tonality(Note.e, Modes.minor);
+  static const eMajor = Tonality(Note.e, TonalMode.major);
+  static const eMinor = Tonality(Note.e, TonalMode.minor);
 
-  static const fMajor = Tonality(Note.f, Modes.major);
-  static const fMinor = Tonality(Note.f, Modes.minor);
+  static const fMajor = Tonality(Note.f, TonalMode.major);
+  static const fMinor = Tonality(Note.f, TonalMode.minor);
 
-  static const fSharpMajor = Tonality(Note.fSharp, Modes.major);
-  static const fSharpMinor = Tonality(Note.fSharp, Modes.minor);
-  static const gFlatMajor = Tonality(Note.gFlat, Modes.major);
+  static const fSharpMajor = Tonality(Note.fSharp, TonalMode.major);
+  static const fSharpMinor = Tonality(Note.fSharp, TonalMode.minor);
+  static const gFlatMajor = Tonality(Note.gFlat, TonalMode.major);
 
-  static const gMajor = Tonality(Note.g, Modes.major);
-  static const gMinor = Tonality(Note.g, Modes.minor);
+  static const gMajor = Tonality(Note.g, TonalMode.major);
+  static const gMinor = Tonality(Note.g, TonalMode.minor);
 
-  static const gSharpMinor = Tonality(Note.gSharp, Modes.minor);
-  static const aFlatMajor = Tonality(Note.aFlat, Modes.major);
-  static const aFlatMinor = Tonality(Note.aFlat, Modes.minor);
+  static const gSharpMinor = Tonality(Note.gSharp, TonalMode.minor);
+  static const aFlatMajor = Tonality(Note.aFlat, TonalMode.major);
+  static const aFlatMinor = Tonality(Note.aFlat, TonalMode.minor);
 
-  static const aMajor = Tonality(Note.a, Modes.major);
-  static const aMinor = Tonality(Note.a, Modes.minor);
+  static const aMajor = Tonality(Note.a, TonalMode.major);
+  static const aMinor = Tonality(Note.a, TonalMode.minor);
 
-  static const aSharpMinor = Tonality(Note.aSharp, Modes.minor);
-  static const bFlatMajor = Tonality(Note.bFlat, Modes.major);
-  static const bFlatMinor = Tonality(Note.bFlat, Modes.minor);
+  static const aSharpMinor = Tonality(Note.aSharp, TonalMode.minor);
+  static const bFlatMajor = Tonality(Note.bFlat, TonalMode.major);
+  static const bFlatMinor = Tonality(Note.bFlat, TonalMode.minor);
 
-  static const bMajor = Tonality(Note.b, Modes.major);
-  static const bMinor = Tonality(Note.b, Modes.minor);
+  static const bMajor = Tonality(Note.b, TonalMode.major);
+  static const bMinor = Tonality(Note.b, TonalMode.minor);
 
   factory Tonality.fromAccidentals(
     int accidentals,
-    Modes mode, [
+    TonalMode mode, [
     Accidental accidental = Accidental.natural,
   ]) =>
       Tonality(
         Note.fromTonalityAccidentals(accidentals, mode, accidental),
         mode,
       );
 
-  /// Returns the [Modes.major] or [Modes.minor] relative [Tonality]
+  /// Returns the [TonalMode.major] or [TonalMode.minor] relative [Tonality]
   /// of this [Tonality].
   ///
   /// Example:
@@ -70,7 +70,7 @@ class Tonality implements Comparable<Tonality> {
         EnharmonicNote(note.semitones)
             .transposeBy(
               Interval.imperfect(
-                3 * (mode == Modes.major ? -1 : 1),
+                3 * (mode == TonalMode.major ? -1 : 1),
                 ImperfectQuality.minor,
               ),
             )

test/src/main.dart

@@ -12,7 +12,7 @@ import 'note/notes_test.dart' as notes_test;
 import 'note/positioned_note_test.dart' as positioned_note_test;
 import 'scale/scale_test.dart' as scale_test;
 import 'tonality/key_signature_test.dart' as key_signature_test;
-import 'tonality/modes_test.dart' as modes_test;
+import 'tonality/mode_test.dart' as mode_test;
 import 'tonality/tonality_test.dart' as tonality_test;
 
 void main() {
@@ -29,6 +29,6 @@ void main() {
   positioned_note_test.main();
   scale_test.main();
   key_signature_test.main();
-  modes_test.main();
+  mode_test.main();
   tonality_test.main();
 }

test/src/tonality/key_signature_test.dart

@@ -45,19 +45,19 @@ void main() {
     group('.tonalities', () {
       test('should return the Set of tonalities for this KeySignature', () {
         expect(const KeySignature(10, Accidental.flat).tonalities, {
-          const Tonality(Note(Notes.e, Accidental.doubleFlat), Modes.major),
-          const Tonality(Note(Notes.c, Accidental.flat), Modes.minor),
+          const Tonality(Note(Notes.e, Accidental.doubleFlat), TonalMode.major),
+          const Tonality(Note(Notes.c, Accidental.flat), TonalMode.minor),
         });
         expect(const KeySignature(9, Accidental.flat).tonalities, {
-          const Tonality(Note(Notes.b, Accidental.doubleFlat), Modes.major),
-          const Tonality(Note.gFlat, Modes.minor),
+          const Tonality(Note(Notes.b, Accidental.doubleFlat), TonalMode.major),
+          const Tonality(Note.gFlat, TonalMode.minor),
         });
         expect(const KeySignature(8, Accidental.flat).tonalities, {
-          const Tonality(Note(Notes.f, Accidental.flat), Modes.major),
-          const Tonality(Note.dFlat, Modes.minor),
+          const Tonality(Note(Notes.f, Accidental.flat), TonalMode.major),
+          const Tonality(Note.dFlat, TonalMode.minor),
         });
         expect(const KeySignature(7, Accidental.flat).tonalities, {
-          const Tonality(Note(Notes.c, Accidental.flat), Modes.major),
+          const Tonality(Note(Notes.c, Accidental.flat), TonalMode.major),
           Tonality.aFlatMinor,
         });
         expect(const KeySignature(6, Accidental.flat).tonalities, {
@@ -117,15 +117,15 @@ void main() {
           Tonality.aSharpMinor,
         });
         expect(const KeySignature(8, Accidental.sharp).tonalities, {
-          const Tonality(Note.gSharp, Modes.major),
-          const Tonality(Note(Notes.e, Accidental.sharp), Modes.minor),
+          const Tonality(Note.gSharp, TonalMode.major),
+          const Tonality(Note(Notes.e, Accidental.sharp), TonalMode.minor),
         });
         expect(const KeySignature(9, Accidental.sharp).tonalities, {
-          const Tonality(Note.dSharp, Modes.major),
-          const Tonality(Note(Notes.b, Accidental.sharp), Modes.minor),
+          const Tonality(Note.dSharp, TonalMode.major),
+          const Tonality(Note(Notes.b, Accidental.sharp), TonalMode.minor),
         });
         expect(const KeySignature(10, Accidental.sharp).tonalities, {
-          const Tonality(Note.aSharp, Modes.major),
+          const Tonality(Note.aSharp, TonalMode.major),
           // TODO(albertms10): Failing test #50:
           //  Should be `Note(Notes.f, Accidental.doubleSharp)`.
           Tonality.gMinor,

test/src/tonality/mode_test.dart

@@ -0,0 +1,36 @@
+import 'dart:collection' show SplayTreeSet;
+
+import 'package:music_notes/music_notes.dart';
+import 'package:test/test.dart';
+
+void main() {
+  group('TonalMode', () {
+    group('.opposite', () {
+      test('should return the correct opposite mode', () {
+        expect(TonalMode.major.opposite, TonalMode.minor);
+        expect(TonalMode.minor.opposite, TonalMode.major);
+      });
+    });
+
+    group('.compareTo', () {
+      test('should correctly sort Mode items in a collection', () {
+        final orderedSet = SplayTreeSet<Mode>.of(const [
+          TonalMode.minor,
+          ModalMode.phrygian,
+          ModalMode.ionian,
+          TonalMode.major,
+          ModalMode.aeolian,
+          ModalMode.lydian,
+        ]);
+        expect(orderedSet.toList(), const [
+          ModalMode.phrygian,
+          ModalMode.aeolian,
+          TonalMode.minor,
+          ModalMode.ionian,
+          TonalMode.major,
+          ModalMode.lydian,
+        ]);
+      });
+    });
+  });
+}

test/src/tonality/tonality_test.dart

@@ -13,7 +13,7 @@ void main() {
         expect(Tonality.gSharpMinor.relative, Tonality.bMajor);
         expect(
           Tonality.aFlatMinor.relative,
-          const Tonality(Note(Notes.c, Accidental.flat), Modes.major),
+          const Tonality(Note(Notes.c, Accidental.flat), TonalMode.major),
         );
       });
     });
@@ -66,12 +66,12 @@ void main() {
         expect(Tonality.aFlatMajor.toString(), 'A♭ major');
         expect(Tonality.fSharpMinor.toString(), 'F♯ minor');
         expect(
-          const Tonality(Note(Notes.g, Accidental.doubleSharp), Modes.major)
+          const Tonality(Note(Notes.g, Accidental.doubleSharp), TonalMode.major)
               .toString(),
           'G𝄪 major',
         );
         expect(
-          const Tonality(Note(Notes.e, Accidental.doubleFlat), Modes.minor)
+          const Tonality(Note(Notes.e, Accidental.doubleFlat), TonalMode.minor)
               .toString(),
           'E𝄫 minor',
         );