Tone.js/test/signal/AudioToGain.js

define(["helper/Offline", "Tone/signal/AudioToGain", "helper/Basic", 
	"Test", "Tone/source/Oscillator", "Tone/signal/Signal", "Tone/signal/Zero", "helper/ConstantOutput"], 
function (Offline, AudioToGain, Basic, Test, Oscillator, Signal, Zero, ConstantOutput) {

	describe("AudioToGain", function(){

		Basic(AudioToGain);

		it("handles input and output connections", function(){
			var a2g = new AudioToGain();
			a2g.connect(Test);
			Test.connect(a2g);
			a2g.dispose();
		});

		it("normalizes an oscillator to 0,1", function(){
			return Offline(function(){
				var osc = new Oscillator(1000);
				var a2g = new AudioToGain();
				osc.connect(a2g);
				a2g.toMaster();
			}).then(function(buffer){
				buffer.forEach(function(sample){
					expect(sample).to.be.within(0, 1);
				});
			});
		});

		it("outputs 0.5 for an input value of 0", function(){
			return ConstantOutput(function(){
				var sig = new Zero();
				var a2g = new AudioToGain();
				sig.connect(a2g);
				a2g.toMaster();
			}, 0.5);
		});

		it("outputs 1 for an input value of 1", function(){
			return ConstantOutput(function(){
				var sig = new Signal(1);
				var a2g = new AudioToGain();
				sig.connect(a2g);
				a2g.toMaster();
			}, 1);
		});

		it("outputs 0 for an input value of -1", function(){
			return ConstantOutput(function(){
				var sig = new Signal(-1);
				var a2g = new AudioToGain();
				sig.connect(a2g);
				a2g.toMaster();
			}, 0);
		});
	});
});