Tone.js/test/signal/Abs.js

define(["Test", "Tone/signal/Abs", "helper/Basic", "Tone/signal/Signal", "helper/ConstantOutput", "helper/Supports"], 
function (Test, Abs, BasicTest, Signal, ConstantOutput, Supports) {

	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);
			});

			if (Supports.WAVESHAPER_0_POSITION){
				
				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);
			});

		});

	});
});