Tone.js/Tone/source/oscillator/PulseOscillator.test.ts

import { expect } from "chai";
import { BasicTests } from "test/helper/Basic";
import { CompareToFile } from "test/helper/CompareToFile";
import { Offline } from "test/helper/Offline";
import { OscillatorTests } from "test/helper/OscillatorTests";
import { SourceTests } from "test/helper/SourceTests";
import { PulseOscillator } from "./PulseOscillator";

describe("PulseOscillator", () => {

	// run the common tests
	BasicTests(PulseOscillator);
	SourceTests(PulseOscillator);
	OscillatorTests(PulseOscillator);

	it("matches a file", () => {
		return CompareToFile(() => {
			const osc = new PulseOscillator({
				width: 0.2,
			}).toDestination();
			osc.start(0);
		}, "pulseOscillator.wav", 0.03);
	});

	context("Phase Rotation", () => {
		it("can change the phase to 90", () => {
			return Offline(() => {
				const osc = new PulseOscillator({
					frequency: 1,
					phase: 90,
					width: 0,
				});
				osc.toDestination();
				osc.start(0);
			}, 1).then(async (buffer) => {
				buffer.forEach((sample, time) => {
					if (time < 0.25) {
						expect(sample).to.be.within(-1, 0);
					} else if (time > 0.25 && time < 0.5) {
						expect(sample).to.be.within(0, 1);
					}
				});
			});
		});

		it("can change the phase to -90", () => {
			return Offline(() => {
				const osc = new PulseOscillator({
					frequency: 1,
					phase: 270,
					width: 0,
				});
				osc.toDestination();
				osc.start(0);
			}, 1).then((buffer) => {
				buffer.forEach((sample, time) => {
					if (time < 0.25) {
						expect(sample).to.be.within(0, 1);
					} else if (time > 0.25 && time < 0.5) {
						expect(sample).to.be.within(-1, 0);
					}
				});
			});
		});

	});

	context("Width", () => {

		it("can set the width", () => {
			const osc = new PulseOscillator({
				width: 0.2,
			});
			expect(osc.width.value).to.be.closeTo(0.2, 0.001);
			osc.dispose();
		});

		it("outputs correctly with a width of 0", () => {
			return Offline(() => {
				const osc = new PulseOscillator({
					frequency: 1,
					width: 0,
				});
				osc.toDestination();
				osc.start(0);
			}, 0.9).then((buffer) => {
				buffer.forEach((sample, time) => {
					if (time > 0.51) {
						expect(sample).to.be.within(-1, 0);
					}
				});
			});
		});

		it("outputs correctly with a width of 0.5", () => {
			return Offline(() => {
				const osc = new PulseOscillator({
					frequency: 1,
					width: 0.5,
				});
				osc.toDestination();
				osc.start(0);
			}, 1).then((buffer) => {
				buffer.forEach((sample, time) => {
					if (time <= 0.5) {
						expect(sample).to.be.within(0, 1);
					} else if (time >= 0.51 && time <= 0.7) {
						expect(sample).to.be.within(-1, 0);
					} else if (time > 0.71) {
						expect(sample).to.be.within(0, 1);
					}
				});
			});
		});
	});

	context("Types", () => {
		it("reports it's type", () => {
			const osc = new PulseOscillator();
			expect(osc.type).to.equal("pulse");
			expect(osc.baseType).to.equal("pulse");
			expect(osc.partials).to.deep.equal([]);
			osc.dispose();
		});
	});
});