Expose song chord definitions with defaults (#864)

src/chord_sheet/chord_pro/chord_definition.ts → src/chord_definition/chord_definition.ts

@@ -1,5 +1,5 @@
-import { Fret } from '../../constants';
-import { parse } from '../../parser/chord_definition/peg_parser';
+import { Fret } from '../constants';
+import { parse } from '../parser/chord_definition/peg_parser';
 
 /**
  * Represents a chord definition.

src/chord_definition/chord_definition_set.ts

@@ -0,0 +1,51 @@
+import ChordDefinition from './chord_definition';
+import chordDefinitions from './defaults.json';
+
+export type DefinitionSet = Record<string, ChordDefinition>;
+
+class ChordDefinitionSet {
+  definitions: DefinitionSet;
+
+  constructor(definitions?: DefinitionSet) {
+    this.definitions = definitions || {};
+  }
+
+  get(chord: string): ChordDefinition | null {
+    return this.definitions[chord] || null;
+  }
+
+  withDefaults() {
+    const defaultDefinitions: Record<string, string> = chordDefinitions;
+    const clone = this.clone();
+
+    Object.keys(defaultDefinitions).forEach((chord: string) => {
+      const definition = ChordDefinition.parse(defaultDefinitions[chord]);
+
+      if (!clone.has(chord)) {
+        clone.add(chord, definition);
+      }
+    });
+
+    return clone;
+  }
+
+  add(chord: string, definition: ChordDefinition) {
+    this.definitions[chord] = definition;
+  }
+
+  has(chord: string): boolean {
+    return chord in this.definitions;
+  }
+
+  clone(): ChordDefinitionSet {
+    const clone = new ChordDefinitionSet();
+
+    Object.keys(this.definitions).forEach((chord: string) => {
+      clone.add(chord, this.definitions[chord].clone());
+    });
+
+    return clone;
+  }
+}
+
+export default ChordDefinitionSet;

src/chord_sheet/song.ts

@@ -16,10 +16,11 @@ import Tag, {
   START_OF_CHORUS,
 } from './tag';
 import SongBuilder from '../song_builder';
-import ChordDefinition from './chord_pro/chord_definition';
+import ChordDefinition from '../chord_definition/chord_definition';
 import Chord from '../chord';
 import FormattingContext from '../formatter/formatting_context';
 import { testSelector } from '../helpers';
+import ChordDefinitionSet from '../chord_definition/chord_definition_set';
 
 type EachItemCallback = (_item: Item) => void;
 
@@ -479,6 +480,10 @@ Or set the song key before changing key:
     return chordDefinitions;
   }
 
+  get chordDefinitions(): ChordDefinitionSet {
+    return new ChordDefinitionSet(this.getChordDefinitions());
+  }
+
   /**
    * Change the song contents inline. Return a new {@link Line} to replace it. Return `null` to remove it.
    * @example

src/chord_sheet/tag.ts

@@ -4,7 +4,7 @@
  */
 import AstComponent from './ast_component';
 import TraceInfo from './trace_info';
-import ChordDefinition from './chord_pro/chord_definition';
+import ChordDefinition from '../chord_definition/chord_definition';
 
 import {
   ABC, BRIDGE, GRID, LILYPOND, TAB, VERSE,

src/chord_sheet_serializer.ts

@@ -22,7 +22,7 @@ import {
 } from './serialized_types';
 import SoftLineBreak from './chord_sheet/soft_line_break';
 import { warn } from './utilities';
-import ChordDefinition from './chord_sheet/chord_pro/chord_definition';
+import ChordDefinition from './chord_definition/chord_definition';
 import SongBuilder from './song_builder';
 
 const CHORD_LYRICS_PAIR = 'chordLyricsPair';

src/index.ts

@@ -1,5 +1,5 @@
 import Chord from './chord';
-import ChordDefinition from './chord_sheet/chord_pro/chord_definition';
+import ChordDefinition from './chord_definition/chord_definition';
 import ChordLyricsPair from './chord_sheet/chord_lyrics_pair';
 import ChordProFormatter from './formatter/chord_pro_formatter';
 import PdfFormatter from './formatter/pdf_formatter';
@@ -51,7 +51,7 @@ import {
 } from './constants';
 
 export { default as Chord } from './chord';
-export { default as ChordDefinition } from './chord_sheet/chord_pro/chord_definition';
+export { default as ChordDefinition } from './chord_definition/chord_definition';
 export { default as ChordLyricsPair } from './chord_sheet/chord_lyrics_pair';
 export { default as ChordProFormatter } from './formatter/chord_pro_formatter';
 export { default as PdfFormatter } from './formatter/pdf_formatter';

src/parser/chord_definition/grammar.pegjs

@@ -64,7 +64,7 @@ Fret
     }
 
 FretNumber
-  = number:[1-9] {
+  = number:[0-9] {
       return parseInt(number, 10);
     }
 

test/chord_sheet/chord_pro/chord_definition.test.ts → test/chord_definition/chord_definition.test.ts

@@ -1,6 +1,6 @@
-import { ChordDefinition } from '../../../src';
-import { Fret } from '../../../src/constants';
-import SUFFIX_MAPPING from '../../../src/normalize_mappings/suffix-normalize-mapping';
+import { ChordDefinition } from '../../src';
+import { Fret } from '../../src/constants';
+import SUFFIX_MAPPING from '../../src/normalize_mappings/suffix-normalize-mapping';
 
 describe('ChordDefinition', () => {
   describe('#clone', () => {

test/chord_definition/chord_definition_set.test.ts

@@ -0,0 +1,50 @@
+import ChordDefinition from '../../src/chord_definition/chord_definition';
+import ChordDefinitionSet from '../../src/chord_definition/chord_definition_set';
+
+describe('ChordDefinitionSet', () => {
+  describe('#get', () => {
+    it('returns a chord definition when present for the chord', () => {
+      const chordDefinition = ChordDefinition.parse(' D7 base-fret 3 frets x 3 2 3 1 x ');
+
+      const definitionSet = new ChordDefinitionSet({
+        'D7': chordDefinition,
+      });
+
+      expect(definitionSet.get('D7')).toEqual(chordDefinition);
+    });
+
+    it('returns null when there is no definition for the chord', () => {
+      const definitionSet = new ChordDefinitionSet();
+
+      expect(definitionSet.get('A')).toBeNull();
+    });
+  });
+
+  describe('#withDefaults', () => {
+    it('loads the defaults for missing definitions', () => {
+      const d7OpenGm = ChordDefinition.parse('D7 base-fret 0 frets 0 2 4 4 2 4');
+      const am = ChordDefinition.parse('Am base-fret 0 frets x 0 2 2 1 0');
+
+      const chordDefinitionSet =
+        new ChordDefinitionSet({
+          'D7': d7OpenGm,
+          'Am': am,
+        })
+          .withDefaults();
+
+      expect(chordDefinitionSet.get('D7')).toEqual(d7OpenGm);
+      expect(chordDefinitionSet.get('Am')).toEqual(am);
+    });
+  });
+
+  describe('#add', () => {
+    it('adds a chord definition for a tuning', () => {
+      const definition = ChordDefinition.parse('A base-fret 0 frets 0 1 2 2 2 0');
+      const library = new ChordDefinitionSet();
+
+      library.add('A', definition);
+
+      expect(library.get('A')).toEqual(definition);
+    });
+  });
+});

test/chord_sheet/song.test.ts

@@ -417,4 +417,24 @@ describe('Song', () => {
       expect(song.getChordDefinitions({ configuration, metadata })).toEqual({ Dm: dm });
     });
   });
+
+  describe('#chordDefinitions', () => {
+    it('returns the unique chord definitions in a song', () => {
+      const cm7 = createChordDefinition('CM7', 3, ['x', '0', 1]);
+      const dm = createChordDefinition('Dm', 3, ['x', 3, 5]);
+
+      const song = createSong([
+        createLine([
+          createTag('chord', 'CM7', cm7),
+        ]),
+        createLine([]),
+        createLine([
+          createTag('define', 'Dm', dm),
+        ]),
+      ]);
+
+      expect(song.chordDefinitions.get('CM7')).toEqual(cm7);
+      expect(song.chordDefinitions.get('Dm')).toEqual(dm);
+    });
+  });
 });

test/utilities.ts

@@ -11,7 +11,7 @@ import Item from '../src/chord_sheet/item';
 import { ChordType, Fret, Modifier } from '../src/constants';
 import Key from '../src/key';
 import ChordSheetSerializer from '../src/chord_sheet_serializer';
-import ChordDefinition from '../src/chord_sheet/chord_pro/chord_definition';
+import ChordDefinition from '../src/chord_definition/chord_definition';
 
 import {
   ContentType,