refactor(null-safety): start migration

lib/music_notes.dart

@@ -2,6 +2,7 @@ library music_notes;
 
 import 'dart:math' as math show min;
 
+import 'package:collection/collection.dart' show IterableExtension;
 import 'package:quiver/core.dart';
 
 part 'src/classes/circle_of_fifths.dart';

lib/src/classes/enharmonic.dart

@@ -4,7 +4,7 @@ abstract class Enharmonic<T extends MusicItem> {
   final Set<T> items;
 
   Enharmonic(this.items)
-      : assert(items != null && items.isNotEmpty),
+      : assert(items.isNotEmpty),
         assert(
           items.every((item) => item.semitones == items.first.semitones),
           '${T}s are not enharmonic.',

lib/src/classes/enharmonic_interval.dart

@@ -32,9 +32,9 @@ class EnharmonicInterval extends Enharmonic<Interval> {
 
     return {
       if (QualitiesValues.exists(intervalBelow, semitones))
-        Interval.fromDesiredSemitones(intervalBelow, semitones),
+        Interval.fromDesiredSemitones(intervalBelow!, semitones),
       if (QualitiesValues.exists(intervalAbove, semitones))
-        Interval.fromDesiredSemitones(intervalAbove, semitones)
+        Interval.fromDesiredSemitones(intervalAbove!, semitones)
     };
   }
 
@@ -51,7 +51,7 @@ class EnharmonicInterval extends Enharmonic<Interval> {
   /// EnharmonicInterval.getInterval(7, Qualities.Disminuida)
   ///   == const Interval(Intervals.Quinta, Qualities.Disminuida)
   /// ```
-  static Interval getInterval(int semitones, [Qualities preferredQuality]) {
+  static Interval getInterval(int semitones, [Qualities? preferredQuality]) {
     final enharmonicIntervals =
         EnharmonicInterval.fromSemitones(semitones).items;
 

lib/src/classes/enharmonic_note.dart

@@ -30,11 +30,11 @@ class EnharmonicNote extends Enharmonic<Note> {
 
     return {
       Note(
-        NotesValues.fromValue(semitones - 1),
+        NotesValues.fromValue(semitones - 1)!,
         Accidentals.Sostingut,
       ),
       Note(
-        NotesValues.fromValue(semitones + 1),
+        NotesValues.fromValue(semitones + 1)!,
         Accidentals.Bemoll,
       ),
     };
@@ -50,7 +50,7 @@ class EnharmonicNote extends Enharmonic<Note> {
   /// EnharmonicNote.getNote(5, Accidentals.Bemoll)
   ///   == const Note(Notes.Fa, Accidentals.Bemoll)
   /// ```
-  static Note getNote(int semitones, [Accidentals preferredAccidental]) {
+  static Note getNote(int semitones, [Accidentals? preferredAccidental]) {
     final enharmonicNotes = EnharmonicNote.fromSemitones(semitones).items;
 
     return enharmonicNotes.firstWhere(

lib/src/classes/interval.dart

@@ -5,9 +5,7 @@ class Interval implements MusicItem {
   final Qualities quality;
   final bool descending;
 
-  const Interval(this.interval, this.quality, {this.descending = false})
-      : assert(interval != null),
-        assert(quality != null);
+  const Interval(this.interval, this.quality, {this.descending = false});
 
   Interval.fromDelta(Intervals interval, int delta)
       : this(interval, qualityFromDelta(interval, delta));

lib/src/classes/key_signature.dart

@@ -2,11 +2,10 @@ part of music_notes;
 
 class KeySignature {
   final int number;
-  final Accidentals accidental;
+  final Accidentals? accidental;
 
   const KeySignature(this.number, [this.accidental])
-      : assert(number != null),
-        assert(number >= 0),
+      : assert(number >= 0),
         assert(number > 0 ? accidental != null : true);
 
   KeySignature.fromDistance(int distance)
@@ -46,7 +45,8 @@ class KeySignature {
       final n = i == iterations
           ? Music.nModValueExcludeZero(number, notesValues)
           : notesValues;
-      list.add('$n × ${accidental.increment(i - 1).toText()}');
+
+      list.add('$n × ${accidental!.increment(i - 1)!.toText()}');
     }
 
     return list.join(', ');

lib/src/classes/note.dart

@@ -2,13 +2,13 @@ part of music_notes;
 
 class Note implements MusicItem {
   final Notes note;
-  final Accidentals accidental;
+  final Accidentals? accidental;
 
-  const Note(this.note, [this.accidental]) : assert(note != null);
+  const Note(this.note, [this.accidental]);
 
   Note.copy(Note note) : this(note.note, note.accidental);
 
-  Note.fromSemitones(int semitones, [Accidentals preferredAccidental])
+  Note.fromSemitones(int semitones, [Accidentals? preferredAccidental])
       : this.copy(EnharmonicNote.getNote(semitones, preferredAccidental));
 
   /// Returns the [Note] from the [Tonality] given its [accidentals] number,
@@ -22,8 +22,11 @@ class Note implements MusicItem {
   /// Note.fromTonalityAccidentals(0, Modes.Menor)
   ///   == const Note(Notes.La)
   /// ```
-  static Note fromTonalityAccidentals(int accidentals, Modes mode,
-      [Accidentals accidental]) {
+  static Note fromTonalityAccidentals(
+    int accidentals,
+    Modes mode, [
+    Accidentals? accidental,
+  ]) {
     final note = fromRawAccidentals(accidentals, accidental);
 
     return mode == Modes.Major
@@ -46,7 +49,7 @@ class Note implements MusicItem {
   /// Note.fromRawAccidentals(0)
   ///   == const Note(Notes.La)
   /// ```
-  static Note fromRawAccidentals(int accidentals, [Accidentals accidental]) =>
+  static Note fromRawAccidentals(int accidentals, [Accidentals? accidental]) =>
       Note.fromSemitones(
         Interval(
                   Intervals.Quinta,
@@ -57,7 +60,7 @@ class Note implements MusicItem {
             1,
         (accidental == Accidentals.Bemoll && accidentals > 8) ||
                 (accidental == Accidentals.Sostingut && accidentals > 10)
-            ? accidental.incremented
+            ? accidental!.incremented
             : accidental,
       );
 
@@ -72,7 +75,7 @@ class Note implements MusicItem {
   int get semitones => Music.modValueExcludeZero(note.value + accidentalValue);
 
   /// Returns this [Note]’s [accidental] value.
-  int get accidentalValue => accidental != null ? accidental.value : 0;
+  int get accidentalValue => accidental?.value ?? 0;
 
   /// Returns the `delta` difference between this [Note] and [note].
   int semitonesDelta(Note note) => Music.modValue(note.semitones - semitones);
@@ -156,7 +159,8 @@ class Note implements MusicItem {
   /// const Note(Notes.La).transposeBySemitones(5)
   ///   == const Note(Notes.Re)
   /// ```
-  Note transposeBySemitones(int semitones, [Accidentals preferredAccidental]) =>
+  Note transposeBySemitones(int semitones,
+          [Accidentals? preferredAccidental]) =>
       Note.fromSemitones(this.semitones + semitones, preferredAccidental);
 
   /// Returns the [Note] transposed by [interval].
@@ -185,7 +189,7 @@ class Note implements MusicItem {
 
   @override
   String toString() =>
-      note.toText() + (accidental != null ? ' ${accidental.toText()}' : '');
+      note.toText() + (accidental != null ? ' ${accidental!.toText()}' : '');
 
   @override
   bool operator ==(other) =>

lib/src/classes/relative_tonalities.dart

@@ -4,8 +4,7 @@ class RelativeTonalities {
   final Set<Tonality> tonalities;
 
   RelativeTonalities(this.tonalities)
-      : assert(tonalities != null),
-        assert(tonalities.length == 2),
+      : assert(tonalities.length == 2),
         assert(
           tonalities.every(
             (tonality) =>

lib/src/classes/tonality.dart

@@ -4,14 +4,12 @@ class Tonality {
   final Note note;
   final Modes mode;
 
-  const Tonality(this.note, this.mode)
-      : assert(note != null),
-        assert(mode != null);
+  const Tonality(this.note, this.mode);
 
   Tonality.copy(Tonality tonality) : this(tonality.note, tonality.mode);
 
   Tonality.fromAccidentals(int accidentals, Modes mode,
-      [Accidentals accidental])
+      [Accidentals? accidental])
       : this(
           Note.fromTonalityAccidentals(accidentals, mode, accidental),
           mode,

lib/src/enums/accidentals.dart

@@ -40,10 +40,10 @@ extension AccidentalsValues on Accidentals {
   /// AccidentalsValues.fromValue(-2) == Accidentals.DobleBemoll
   /// AccidentalsValues.fromValue(3) == Accidentals.TripleSostingut
   /// ```
-  static Accidentals fromValue(int value) => accidentalsValues.keys.firstWhere(
+  static Accidentals? fromValue(int value) =>
+      accidentalsValues.keys.firstWhereOrNull(
         (accidental) =>
             Music.modValue(value + 3) - 3 == accidentalsValues[accidental],
-        orElse: () => null,
       );
 
   /// Returns the value of this [Accidentals] enum item in [accidentalsValues].
@@ -53,7 +53,7 @@ extension AccidentalsValues on Accidentals {
   /// Accidentals.Bemoll.value == -1
   /// Accidentals.DobleSostingut.value == 2
   /// ```
-  int get value => accidentalsValues[this];
+  int get value => accidentalsValues[this]!;
 
   /// Returns the symbol of this [Accidentals] enum item.
   ///
@@ -62,7 +62,7 @@ extension AccidentalsValues on Accidentals {
   /// Accidentals.Bemoll.symbol == '♭'
   /// Accidentals.DobleSostingut.symbol == '𝄪'
   /// ```
-  String get symbol => accidentalsSymbols[this];
+  String get symbol => accidentalsSymbols[this]!;
 
   /// Returns the incremented [Accidentals] enum item of this.
   ///
@@ -71,7 +71,7 @@ extension AccidentalsValues on Accidentals {
   /// Accidentals.DobleBemoll.incremented == Accidentals.TripleBemoll
   /// Accidentals.Sostingut.incremented == Accidentals.DobleSostingut
   /// ```
-  Accidentals get incremented => increment(1);
+  Accidentals get incremented => increment(1)!;
 
   /// Returns the decremented [Accidentals] enum item of this.
   ///
@@ -80,7 +80,7 @@ extension AccidentalsValues on Accidentals {
   /// Accidentals.DobleBemoll.decremented == Accidentals.Bemoll
   /// Accidentals.Sostingut.decremented == Accidentals.Becaire
   /// ```
-  Accidentals get decremented => decrement(1);
+  Accidentals get decremented => decrement(1)!;
 
   /// Returns the incremented [Accidentals] enum item of this by [n].
   ///
@@ -89,7 +89,7 @@ extension AccidentalsValues on Accidentals {
   /// Accidentals.Bemoll.increment(2) == Accidentals.TripleBemoll
   /// Accidentals.Sostingut.increment(1) == Accidentals.DobleSostingut
   /// ```
-  Accidentals increment(int n) =>
+  Accidentals? increment(int n) =>
       fromValue((value.abs() + n) * (value > 0 ? 1 : -1));
 
   /// Returns the decremented [Accidentals] enum item of this by [n].
@@ -102,5 +102,5 @@ extension AccidentalsValues on Accidentals {
   /// Accidentals.Sostingut.decrement(1) == Accidentals.Becaire
   /// Accidentals.DobleBemoll.decrement(4) == Accidentals.DobleSostingut
   /// ```
-  Accidentals decrement(int n) => increment(-n);
+  Accidentals? decrement(int n) => increment(-n);
 }

lib/src/enums/enums_to_string.dart

@@ -1,21 +1,21 @@
 part of music_notes;
 
 extension on Notes {
-  String toText() => toString().split('.')[1];
+  String toText() => toString().split('.').last;
 }
 
 extension on Accidentals {
-  String toText() => toString().split('.')[1];
+  String toText() => toString().split('.').last;
 }
 
 extension on Modes {
-  String toText() => toString().split('.')[1];
+  String toText() => toString().split('.').last;
 }
 
 extension on Intervals {
-  String toText() => toString().split('.')[1];
+  String toText() => toString().split('.').last;
 }
 
 extension on Qualities {
-  String toText() => toString().split('.')[1];
+  String toText() => toString().split('.').last;
 }

lib/src/enums/intervals.dart

@@ -41,11 +41,11 @@ extension IntervalsValues on Intervals {
   /// IntervalsValues.fromSemitones(0) == Intervals.Unison
   /// IntervalsValues.fromSemitones(4) == null
   /// ```
-  static Intervals fromSemitones(int semitones) => Intervals.values.firstWhere(
+  static Intervals? fromSemitones(int semitones) =>
+      Intervals.values.firstWhereOrNull(
         (interval) =>
             Music.modValueExcludeZero(semitones) ==
             intervalsQualitiesIndex[interval],
-        orElse: () => null,
       );
 
   /// Returns an [Intervals] enum item that matches [ordinal].
@@ -79,7 +79,7 @@ extension IntervalsValues on Intervals {
   /// ```
   int get semitones =>
       intervalsQualitiesIndex[this] ??
-      Music.chromaticDivisions + intervalsQualitiesIndex[inverted];
+      Music.chromaticDivisions + intervalsQualitiesIndex[inverted]!;
 
   /// Returns the ordinal number of this [Intervals] enum item.
   ///

lib/src/enums/notes.dart

@@ -22,9 +22,8 @@ extension NotesValues on Notes {
   /// NotesValues.fromValue(8) == Notes.Sol
   /// NotesValues.fromValue(11) == null
   /// ```
-  static Notes fromValue(int value) => notesValues.keys.firstWhere(
+  static Notes? fromValue(int value) => notesValues.keys.firstWhereOrNull(
         (note) => Music.modValueExcludeZero(value) == notesValues[note],
-        orElse: () => null,
       );
 
   /// Returns a [Notes] enum item that matches [ordinal].
@@ -65,7 +64,7 @@ extension NotesValues on Notes {
   /// Notes.Sol.value == 8
   /// Notes.Si.value == 12
   /// ```
-  int get value => notesValues[this];
+  int get value => notesValues[this]!;
 
   /// Returns an [Intervals] enum item that conforms an interval
   /// between this [Notes] enum item and [note] in ascending manner by default.

lib/src/enums/qualities.dart

@@ -44,7 +44,9 @@ extension QualitiesValues on Qualities {
   /// QualitiesValues.exists(Intervals.Sexta, 8) == true
   /// QualitiesValues.exists(Intervals.Sexta, 10) == false
   /// ```
-  static bool exists(Intervals interval, int semitones) {
+  static bool exists(Intervals? interval, int semitones) {
+    if (interval == null) return false;
+
     final delta = semitones - interval.semitones + (interval.isPerfect ? 0 : 1);
     return delta > 0 && delta <= intervalQualitiesSet(interval).length;
   }

pubspec.yaml

@@ -6,11 +6,12 @@ author: albertms10
 repository: https://github.com/albertms10/music_notes.git
 
 environment:
-  sdk: '>=2.10.0 <3.0.0'
+  sdk: ">=2.12.0-0 <3.0.0"
 
 dependencies:
-  quiver: ^2.1.5
-  test: ^1.14.6
+  quiver: ^3.0.0-nullsafety.3
+  test: ^1.16.0-nullsafety.16
+  collection: ^1.15.0-nullsafety.4
 
 dev_dependencies:
-  pedantic: ^1.0.0
+  pedantic: ^1.10.0-nullsafety.3