(Gsoc'21)➕Added tests for metro.js and fixed a bug

Author: satyasaibhushan

src/metro.js

@@ -60,7 +60,8 @@ class Metro {
   }
 
   getBPM() {
-    return (this.clock.getRate() / this.tatums) * 60;
+    return this.bpm;
+    // return (this.clock.getRate() / this.tatums) * 60;
   }
 
   _init() {
@@ -78,6 +79,7 @@ class Metro {
     this.syncedParts.push(part);
   }
 
+  //timeFromNow is in seconds
   start(timeFromNow) {
     var t = timeFromNow || 0;
     var now = p5sound.audiocontext.currentTime;

test/tests.js

@@ -2,6 +2,7 @@ import('./tests/main.js');
 import('./tests/p5.Helpers.js');
 import('./tests/p5.Distortion.js');
 import('./tests/p5.AudioContext.js');
+import('./tests/p5.Metro.js')
 import('./tests/p5.Effect.js');
 import('./tests/p5.Filter.js');
 import('./tests/p5.Gain.js');

test/tests/p5.Metro.js

@@ -0,0 +1,85 @@
+const expect = chai.expect;
+let metro;
+
+describe('p5.Metro', function () {
+  beforeEach(function () {
+    metro = new p5.Metro();
+  });
+
+  it('can be created', function () {
+    expect(metro).to.have.property('bpm').to.equal(120);
+    expect(metro).to.have.property('clock');
+    expect(metro).to.have.property('syncedParts').to.be.an('array');
+  });
+
+  it('can be initialised with a beatlength, bpm', function () {
+    metro.beatLength(0.0625);
+    metro.setBPM(60);
+    expect(metro.tatums).to.equal(4);
+    expect(metro.tatumTime).to.equal(0.25);
+    expect(metro.getBPM()).to.equal(60);
+  });
+
+  it('can be started and stopped', function (done) {
+    this.timeout = 2000;
+    let ticks;
+    metro.setBPM(600);
+    metro.start();
+    setTimeout(() => {
+      ticks = metro.metroTicks;
+      metro.stop();
+      expect(ticks).to.not.equal(0);
+      setTimeout(() => {
+        expect(metro.metroTicks).to.equal(ticks);
+        done();
+      }, 100);
+    }, 1000);
+  });
+
+  it('can be started and stopped with dealy', function (done) {
+    let ticks;
+    metro.setBPM(600);
+    metro.start(0.1);
+    setTimeout(() => {
+      ticks = metro.metroTicks;
+      metro.stop(0.2);
+      expect(ticks).to.not.equal(0);
+      setTimeout(() => {
+        expect(metro.metroTicks).to.not.equal(ticks);
+      }, 100);
+      setTimeout(() => {
+        ticks = metro.metroTicks;
+        setTimeout(() => {
+          expect(metro.metroTicks).to.equal(ticks);
+          done();
+        }, 100);
+      }, 200);
+    }, 1000);
+  });
+
+  it('can sync parts', function () {
+    let part = new p5.Part();
+    part.addPhrase('snare', () => {}, [0, 0, 1, 0]);
+    part.setBPM(60);
+    part.noLoop();
+    part.start();
+    expect(metro.syncedParts.length).to.equal(0);
+    metro.resetSync(part);
+    expect(metro.syncedParts.length).to.equal(1);
+  });
+
+  it('parts can be pushed into syncedParts', function () {
+    let phraseAttack = new p5.Phrase('testerAttack', () => {}, [1, 0, 0, 0]);
+    let part = new p5.Part();
+    part.addPhrase(phraseAttack);
+    part.setBPM(60);
+    part.start();
+    expect(metro.syncedParts.length).to.equal(0);
+    metro.pushSync(part);
+    expect(metro.syncedParts.length).to.equal(1);
+    metro.pushSync(part);
+    expect(metro.syncedParts.length).to.equal(2);
+    metro.resetSync(part);
+    expect(metro.syncedParts.length).to.equal(1);
+  });
+});