feat(harmony): make Chord implement extracted Chordable mixin met…

…hods (#175)

* feat(harmony): make `Chord` implement extracted `Chordable` mixin methods

* docs(chord): add missing type parameter to `Chord` reference

* docs(scale): add missing type parameter in `Scale` references

* docs: add missing type parameters in references

* test(chord): add missing test cases for `add13` and `add` methods

* chore(settings): add lowercase `chordable` cSpell word

.vscode/settings.json

@@ -1,6 +1,8 @@
 {
   "cSpell.ignoreWords": ["music"],
   "cSpell.words": [
+    "chordable",
+    "Chordable",
     "dorian",
     "helmholtz",
     "heptatonic",

lib/music_notes.dart

@@ -11,6 +11,7 @@ import 'utils/int_mod_extension.dart';
 import 'utils/iterable.dart';
 import 'utils/num_extension.dart';
 
+part 'src/chordable.dart';
 part 'src/enharmonic.dart';
 part 'src/harmony/chord.dart';
 part 'src/harmony/chord_pattern.dart';

lib/src/chordable.dart

@@ -0,0 +1,44 @@
+part of '../music_notes.dart';
+
+mixin Chordable<T> {
+  /// Returns a new [T] with an [ImperfectQuality.augmented] root triad.
+  T get augmented;
+
+  /// Returns a new [T] with an [ImperfectQuality.major] root triad.
+  T get major;
+
+  /// Returns a new [T] with an [ImperfectQuality.minor] root triad.
+  T get minor;
+
+  /// Returns a new [T] with an [ImperfectQuality.diminished] root triad.
+  T get diminished;
+
+  /// Returns a new [T] with a suspended [Interval.majorSecond].
+  T sus2() => add(Interval.majorSecond, replaceSizes: const [3, 4]);
+
+  /// Returns a new [T] with a suspended [Interval.perfectFourth].
+  T sus4() => add(Interval.perfectFourth, replaceSizes: const [2, 3]);
+
+  /// Returns a new [T] adding a [quality] 6th.
+  T add6([ImperfectQuality quality = ImperfectQuality.major]) =>
+      add(Interval.imperfect(6, quality));
+
+  /// Returns a new [T] adding a [quality] 7th.
+  T add7([ImperfectQuality quality = ImperfectQuality.minor]) =>
+      add(Interval.imperfect(7, quality));
+
+  /// Returns a new [T] adding a [quality] 9th.
+  T add9([ImperfectQuality quality = ImperfectQuality.major]) =>
+      add(Interval.imperfect(9, quality));
+
+  /// Returns a new [T] adding an [quality] 11th.
+  T add11([PerfectQuality quality = PerfectQuality.perfect]) =>
+      add(Interval.perfect(11, quality));
+
+  /// Returns a new [T] adding a [quality] 13th.
+  T add13([ImperfectQuality quality = ImperfectQuality.major]) =>
+      add(Interval.imperfect(13, quality));
+
+  /// Returns a new [T] adding [interval].
+  T add(Interval interval, {List<int>? replaceSizes});
+}

lib/src/enharmonic.dart

@@ -3,10 +3,10 @@ part of '../music_notes.dart';
 @immutable
 abstract interface class Enharmonic<T> implements Comparable<Enharmonic<T>> {
   /// The number of semitones of the common chromatic pitch of this
-  /// [Enharmonic].
+  /// [Enharmonic<T>].
   final int semitones;
 
-  /// Creates a new [Enharmonic].
+  /// Creates a new [Enharmonic<T>].
   const Enharmonic(this.semitones);
 
   /// Returns the different spellings sharing the same number of [semitones].

lib/src/harmony/chord.dart

@@ -1,16 +1,18 @@
 part of '../../music_notes.dart';
 
-class Chord<T extends Scalable<T>> implements Transposable<Chord<T>> {
-  /// The [Scalable<T>] items this [Chord] is built of.
+class Chord<T extends Scalable<T>>
+    with Chordable<Chord<T>>
+    implements Transposable<Chord<T>> {
+  /// The [Scalable<T>] items this [Chord<T>] is built of.
   final List<T> items;
 
-  /// Creates a new [Chord] from [items].
+  /// Creates a new [Chord<T>] from [items].
   const Chord(this.items);
 
-  /// The root [Scalable<T>] of this [Chord].
+  /// The root [Scalable<T>] of this [Chord<T>].
   T get root => items.first;
 
-  /// Returns the [ChordPattern] for this [Chord].
+  /// Returns the [ChordPattern] for this [Chord<T>].
   ///
   /// The pattern is calculated based on the intervals between the notes rather
   /// than from the root note. This approach helps differentiate compound
@@ -26,7 +28,65 @@ class Chord<T extends Scalable<T>> implements Transposable<Chord<T>> {
   /// ```
   ChordPattern get pattern => ChordPattern.intervalSteps(items.intervals);
 
-  /// Returns a transposed [Chord] by [interval] from this [Chord].
+  /// Returns the list of modifier [T]s from the root note.
+  ///
+  /// Example:
+  /// ```dart
+  /// Note.a.majorTriad.add7().add9().modifiers == const [Note.g, Note.b]
+  /// ```
+  List<T> get modifiers => items.skip(3).toList();
+
+  /// Returns a new [Chord<T>] with an [ImperfectQuality.augmented] root
+  /// triad.
+  ///
+  /// Example:
+  /// ```dart
+  /// Note.c.majorTriad.add7().augmented
+  ///   == Chord([Note.c, Note.e, Note.g.sharp, Note.b.flat])
+  /// ```
+  @override
+  Chord<T> get augmented =>
+      Chord([...ChordPattern.augmentedTriad.on(root).items, ...modifiers]);
+
+  /// Returns a new [Chord<T>] with an [ImperfectQuality.major] root triad.
+  ///
+  /// Example:
+  /// ```dart
+  /// Note.c.minorTriad.add7().major
+  ///   == Chord([Note.c, Note.e, Note.g, Note.b.flat])
+  /// ```
+  @override
+  Chord<T> get major =>
+      Chord([...ChordPattern.majorTriad.on(root).items, ...modifiers]);
+
+  /// Returns a new [Chord<T>] with an [ImperfectQuality.minor] root triad.
+  ///
+  /// Example:
+  /// ```dart
+  /// Note.c.majorTriad.add7().minor
+  ///   == Chord([Note.c, Note.e.flat, Note.g, Note.b.flat])
+  /// ```
+  @override
+  Chord<T> get minor =>
+      Chord([...ChordPattern.minorTriad.on(root).items, ...modifiers]);
+
+  /// Returns a new [Chord<T>] with an [ImperfectQuality.diminished] root triad.
+  ///
+  /// Example:
+  /// ```dart
+  /// Note.c.majorTriad.add7().diminished
+  ///   == Chord([Note.c, Note.e.flat, Note.g.flat, Note.b.flat])
+  /// ```
+  @override
+  Chord<T> get diminished =>
+      Chord([...ChordPattern.diminishedTriad.on(root).items, ...modifiers]);
+
+  /// Returns a new [Chord<T>] adding [interval].
+  @override
+  Chord<T> add(Interval interval, {List<int>? replaceSizes}) =>
+      pattern.add(interval, replaceSizes: replaceSizes).on(root);
+
+  /// Returns a transposed [Chord<T>] by [interval] from this [Chord<T>].
   ///
   /// Example:
   /// ```dart

lib/src/harmony/chord_pattern.dart

@@ -1,6 +1,6 @@
 part of '../../music_notes.dart';
 
-class ChordPattern {
+class ChordPattern with Chordable<ChordPattern> {
   /// The intervals from the root note.
   final List<Interval> intervals;
 
@@ -119,6 +119,7 @@ class ChordPattern {
   ///        Interval.minorSeventh
   ///      ])
   /// ```
+  @override
   ChordPattern get augmented =>
       ChordPattern([...augmentedTriad.intervals, ...modifiers]);
 
@@ -134,6 +135,7 @@ class ChordPattern {
   ///        Interval.minorSeventh
   ///      ])
   /// ```
+  @override
   ChordPattern get major =>
       ChordPattern([...majorTriad.intervals, ...modifiers]);
 
@@ -149,6 +151,7 @@ class ChordPattern {
   ///        Interval.minorSeventh
   ///      ])
   /// ```
+  @override
   ChordPattern get minor =>
       ChordPattern([...minorTriad.intervals, ...modifiers]);
 
@@ -164,37 +167,12 @@ class ChordPattern {
   ///        Interval.minorSeventh
   ///      ])
   /// ```
+  @override
   ChordPattern get diminished =>
       ChordPattern([...diminishedTriad.intervals, ...modifiers]);
 
-  /// Returns a new [ChordPattern] with a suspended [Interval.majorSecond].
-  ChordPattern sus2() => add(Interval.majorSecond, replaceSizes: const [3, 4]);
-
-  /// Returns a new [ChordPattern] with a suspended [Interval.perfectFourth].
-  ChordPattern sus4() =>
-      add(Interval.perfectFourth, replaceSizes: const [2, 3]);
-
-  /// Returns a new [ChordPattern] adding a [quality] 6th.
-  ChordPattern add6([ImperfectQuality quality = ImperfectQuality.major]) =>
-      add(Interval.imperfect(6, quality));
-
-  /// Returns a new [ChordPattern] adding a [quality] 7th.
-  ChordPattern add7([ImperfectQuality quality = ImperfectQuality.minor]) =>
-      add(Interval.imperfect(7, quality));
-
-  /// Returns a new [ChordPattern] adding a [quality] 9th.
-  ChordPattern add9([ImperfectQuality quality = ImperfectQuality.major]) =>
-      add(Interval.imperfect(9, quality));
-
-  /// Returns a new [ChordPattern] adding an [quality] 11th.
-  ChordPattern add11([PerfectQuality quality = PerfectQuality.perfect]) =>
-      add(Interval.perfect(11, quality));
-
-  /// Returns a new [ChordPattern] adding a [quality] 13th.
-  ChordPattern add13([ImperfectQuality quality = ImperfectQuality.major]) =>
-      add(Interval.imperfect(13, quality));
-
   /// Returns a new [ChordPattern] adding [interval].
+  @override
   ChordPattern add(Interval interval, {List<int>? replaceSizes}) {
     final sizesToReplace = [interval.size, ...?replaceSizes];
     final filteredIntervals = intervals.whereNot(

lib/src/scale/scale.dart

@@ -1,20 +1,21 @@
 part of '../../music_notes.dart';
 
 class Scale<T extends Scalable<T>> implements Transposable<Scale<T>> {
-  /// The [Scalable] degrees that define this [Scale].
+  /// The [Scalable<T>] degrees that define this [Scale<T>].
   final List<T> degrees;
 
-  /// The descending [Scalable] degrees that define this [Scale] (if different).
+  /// The descending [Scalable<T>] degrees that define this [Scale<T>] (if
+  /// different).
   final List<T>? _descendingDegrees;
 
-  /// Creates a new [Scale] instance from [degrees].
+  /// Creates a new [Scale<T>] instance from [degrees].
   const Scale(this.degrees, [this._descendingDegrees]);
 
-  /// The descending [Scalable] degrees that define this [Scale].
+  /// The descending [Scalable<T>] degrees that define this [Scale<T>].
   List<T> get descendingDegrees =>
       _descendingDegrees ?? degrees.reversed.toList();
 
-  /// Returns the [ScalePattern] of this [Scale].
+  /// Returns the [ScalePattern] of this [Scale<T>].
   ///
   /// Example:
   /// ```dart
@@ -24,7 +25,7 @@ class Scale<T extends Scalable<T>> implements Transposable<Scale<T>> {
   ScalePattern get pattern =>
       ScalePattern(degrees.intervals, _descendingDegrees?.descendingIntervals);
 
-  /// Returns the reversed of this [Scale].
+  /// Returns the reversed of this [Scale<T>].
   ///
   /// Example:
   /// ```dart
@@ -35,7 +36,7 @@ class Scale<T extends Scalable<T>> implements Transposable<Scale<T>> {
   Scale<T> get reversed =>
       Scale(descendingDegrees, _descendingDegrees != null ? degrees : null);
 
-  /// Returns the [Chord] for each [ScaleDegree] of this [Scale].
+  /// Returns the [Chord<T>] for each [ScaleDegree] of this [Scale<T>].
   ///
   /// Example:
   /// ```dart
@@ -52,7 +53,7 @@ class Scale<T extends Scalable<T>> implements Transposable<Scale<T>> {
   List<Chord<T>> get degreeChords =>
       [for (var i = 1; i < degrees.length; i++) degreeChord(ScaleDegree(i))];
 
-  /// Returns the [T] for the [scaleDegree] of this [Scale].
+  /// Returns the [T] for the [scaleDegree] of this [Scale<T>].
   ///
   /// Example:
   /// ```dart
@@ -72,7 +73,7 @@ class Scale<T extends Scalable<T>> implements Transposable<Scale<T>> {
     );
   }
 
-  /// Returns the [Chord] for the [scaleDegree] of this [Scale].
+  /// Returns the [Chord<T>] for the [scaleDegree] of this [Scale<T>].
   ///
   /// Example:
   /// ```dart
@@ -82,7 +83,7 @@ class Scale<T extends Scalable<T>> implements Transposable<Scale<T>> {
   Chord<T> degreeChord(ScaleDegree scaleDegree) =>
       pattern.degreePattern(scaleDegree).on(degree(scaleDegree));
 
-  /// Returns this [Scale] transposed by [interval].
+  /// Returns this [Scale<T>] transposed by [interval].
   ///
   /// Example:
   /// ```dart