Tone.js/test/signal/Abs.js

import Test from "helper/Test";
import Abs from "Tone/signal/Abs";
import BasicTest from "helper/Basic";
import Signal from "Tone/signal/Signal";
import ConstantOutput from "helper/ConstantOutput";

describe("Abs", function(){

	BasicTest(Abs);

	context("Absolute Value", function(){

		it("handles input and output connections", function(){
			var abs = new Abs();
			Test.connect(abs);
			abs.connect(Test);
			abs.dispose();
		});

		it("outputs the same value for positive values", function(){
			return ConstantOutput(function(){
				var signal = new Signal(0.4);
				var abs = new Abs();
				signal.connect(abs);
				abs.toMaster();
			}, 0.4);
		});

		it("outputs 0 when the input is 0", function(){
			return ConstantOutput(function(){
				var signal = new Signal(0);
				var abs = new Abs();
				signal.connect(abs);
				abs.toMaster();
			}, 0);
		});

		it("outputs the absolute value for negative numbers", function(){
			return ConstantOutput(function(){
				var signal = new Signal(-0.3);
				var abs = new Abs();
				signal.connect(abs);
				abs.toMaster();
			}, 0.3);
		});

	});

});