feat(alphatex): beat level lyrics with importer/exporter

Author: Danielku15

src/exporter/AlphaTexExporter.ts

@@ -524,8 +524,6 @@ export class AlphaTexExporter extends ScoreExporter {
                 this.writeChordTo(writer, chord);
             }
         }
-
-        // TODO: lyrics
     }
 
     private writeChordTo(writer: AlphaTexWriter, c: Chord) {
@@ -949,6 +947,18 @@ export class AlphaTexExporter extends ScoreExporter {
             writer.writeString(beat.text);
         }
 
+        if (beat.lyrics != null && beat.lyrics!.length > 0) {
+            if (beat.lyrics.length > 1) {
+                for (let i = 0; i < beat.lyrics.length; i++) {
+                    writer.writeGroupItem(`lyrics ${i} `);
+                    writer.writeString(beat.lyrics[i]);
+                }
+            } else {
+                writer.writeGroupItem('lyrics ');
+                writer.writeString(beat.lyrics[0]);
+            }
+        }
+
         switch (beat.graceType) {
             case GraceType.OnBeat:
                 writer.writeGroupItem('gr ob');

src/importer/AlphaTexImporter.ts

@@ -302,10 +302,7 @@ export class AlphaTexLexer {
                     // unicode handling
 
                     // https://tc39.es/ecma262/multipage/ecmascript-data-types-and-values.html#sec-ecmascript-language-types-string-type
-                    if (
-                        IOHelper.isLeadingSurrogate(previousCodepoint) &&
-                        IOHelper.isTrailingSurrogate(codepoint)
-                    ) {
+                    if (IOHelper.isLeadingSurrogate(previousCodepoint) && IOHelper.isTrailingSurrogate(codepoint)) {
                         codepoint = (previousCodepoint - 0xd800) * 0x400 + (codepoint - 0xdc00) + 0x10000;
                         s += String.fromCodePoint(codepoint);
                     } else if (IOHelper.isLeadingSurrogate(codepoint)) {
@@ -316,7 +313,7 @@ export class AlphaTexLexer {
                             s += String.fromCodePoint(previousCodepoint);
                         }
 
-                        if(codepoint > 0){
+                        if (codepoint > 0) {
                             s += String.fromCodePoint(codepoint);
                         }
                     }
@@ -2132,6 +2129,29 @@ export class AlphaTexImporter extends ScoreImporter {
                 return false;
             }
             beat.text = this.syData as string;
+        } else if (syData === 'lyrics') {
+            this.sy = this.newSy();
+
+            let lyricsLine = 0;
+            if (this.sy === AlphaTexSymbols.Number) {
+                lyricsLine = this.syData as number;
+                this.sy = this.newSy();
+            }
+
+            if (this.sy !== AlphaTexSymbols.String) {
+                this.error('lyrics', AlphaTexSymbols.String, true);
+                return false;
+            }
+
+            if (!beat.lyrics) {
+                beat.lyrics = [];
+            }
+
+            while (beat.lyrics!.length <= lyricsLine) {
+                beat.lyrics.push('');
+            }
+
+            beat.lyrics[lyricsLine] = this.syData as string;
         } else if (syData === 'dd') {
             beat.dots = 2;
         } else if (syData === 'd') {

test/importer/AlphaTexImporter.test.ts

@@ -2298,6 +2298,34 @@ describe('AlphaTexImporterTest', () => {
     it('utf16', () => {
         const score = parseTex(`\\title "🤘🏻" .`);
 
-        expect(score.title).to.equal("🤘🏻");
+        expect(score.title).to.equal('🤘🏻');
+    });
+
+    it('beat-lyrics', () => {
+        const score = parseTex(`
+            .
+            3.3.3 
+            3.3.3 {lyrics "A"} 
+            3.3.3 {lyrics 0 "B C D"} 
+            3.3.3 {lyrics 0 "E" lyrics 1 "F" lyrics 2 "G"} 
+        `);
+
+        expect(score.tracks[0].staves[0].bars[0].voices[0].beats[0].lyrics).to.not.be.ok;
+
+        expect(score.tracks[0].staves[0].bars[0].voices[0].beats[1].lyrics).to.be.ok;
+        expect(score.tracks[0].staves[0].bars[0].voices[0].beats[1].lyrics!.length).to.equal(1);
+        expect(score.tracks[0].staves[0].bars[0].voices[0].beats[1].lyrics![0]).to.equal('A');
+
+        expect(score.tracks[0].staves[0].bars[0].voices[0].beats[2].lyrics).to.be.ok;
+        expect(score.tracks[0].staves[0].bars[0].voices[0].beats[2].lyrics!.length).to.equal(1);
+        expect(score.tracks[0].staves[0].bars[0].voices[0].beats[2].lyrics![0]).to.equal('B C D');
+
+        expect(score.tracks[0].staves[0].bars[0].voices[0].beats[3].lyrics).to.be.ok;
+        expect(score.tracks[0].staves[0].bars[0].voices[0].beats[3].lyrics!.length).to.equal(3);
+        expect(score.tracks[0].staves[0].bars[0].voices[0].beats[3].lyrics![0]).to.equal('E');
+        expect(score.tracks[0].staves[0].bars[0].voices[0].beats[3].lyrics![1]).to.equal('F');
+        expect(score.tracks[0].staves[0].bars[0].voices[0].beats[3].lyrics![2]).to.equal('G');
+
+        testExportRoundtrip(score);
     });
 });

test/model/ComparisonHelpers.ts

@@ -81,33 +81,22 @@ export class ComparisonHelpers {
 
         ignoreKeys = ignoreKeys ?? [];
         ignoreKeys.push(
-            // score level
-            'stylesheet',
-
-            // track level
-            'color',
-
             // staff level
             'chords', // ids differ
             'percussionarticulations', // unsupported
 
             // playback info
             'port',
-            'volume',
             'primarychannel',
             'secondarychannel',
             'balance',
 
             // beat level
             'chordid', // ids differ
-            'lyrics', // missing feature
-            'preferredbeamdirection',
             'timer', // value will be calculated, only showTimer is important here
 
             // note level
-            'accidentalmode',
             'ratioposition',
-            'percussionarticulation',
 
             // for now ignore the automations as they get reorganized from beat to masterbar level
             // which messes with the 1:1 validation