Tone.js/test/component/Volume.js

define(["Tone/component/Volume", "helper/Basic", "helper/Offline", "Test", 
	"Tone/signal/Signal", "helper/PassAudio", "helper/PassAudioStereo"], 
function (Volume, Basic, Offline, Test, Signal, PassAudio, PassAudioStereo) {
	describe("Volume", function(){

		Basic(Volume);

		context("Volume", function(){

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

			it("can be constructed with volume value", function(){
				var vol = new Volume(-12);
				expect(vol.volume.value).to.be.closeTo(-12, 0.1);
				vol.dispose();
			});

			it("can be constructed with an options object", function(){
				var vol = new Volume({
					"volume" : 2
				});
				expect(vol.volume.value).to.be.closeTo(2, 0.1);
				vol.dispose();
			});

			it("can be constructed with an options object and muted", function(){
				var vol = new Volume({
					"mute" : true
				});
				expect(vol.mute).to.be.true;
				vol.dispose();
			});

			it("can set/get with an object", function(){
				var vol = new Volume();
				vol.set({
					"volume" : -10
				});
				expect(vol.get().volume).to.be.closeTo(-10, 0.1);
				vol.dispose();
			});

			it("unmuting returns to previous volume", function(){
				var vol = new Volume(-10);
				vol.mute = true;
				expect(vol.mute).to.be.true;
				expect(vol.volume.value).to.equal(-Infinity);
				vol.mute = false;
				//returns the volume to what it was
				expect(vol.volume.value).to.be.closeTo(-10, 0.1);
				vol.dispose();
			});

			it("passes the incoming signal through", function(){
				return PassAudio(function(input){
					var vol = new Volume().toMaster();
					input.connect(vol);
				});
			});

			it("passes the incoming stereo signal through", function(){
				return PassAudioStereo(function(input){
					var vol = new Volume().toMaster();
					input.connect(vol);
				});
			});

			it("can lower the volume", function(){
				return Offline(function(){
					var vol = new Volume(-10).toMaster();
					new Signal(1).connect(vol);
				}).then(function(buffer){
					buffer.getRMS().forEach(function(level){
						expect(level).to.be.closeTo(0.315, 0.01);
					});
				});
			});

			it("can mute the volume", function(){
				return Offline(function(){
					var vol = new Volume(0).toMaster();
					new Signal(1).connect(vol);
					vol.mute = true;
				}).then(function(buffer){
					expect(buffer.isSilent()).to.be.true;
				});
			});

			it("muted when volume is set to -Infinity", function(){
				return Offline(function(){
					var vol = new Volume(-Infinity).toMaster();
					new Signal(1).connect(vol);
					expect(vol.mute).to.be.true;
				}).then(function(buffer){
					expect(buffer.isSilent()).to.be.true;
				});
			});

			it("setting the volume unmutes it and reports itself as unmuted", function(){
				var vol = new Volume(0).toMaster();
				vol.mute = true;
				expect(vol.mute).to.be.true;
				vol.volume.value = 0
				expect(vol.mute).to.be.false;
				vol.dispose();
			});

			it("multiple calls to mute still return the vol to the original", function(){
				var vol = new Volume(-20);
				vol.mute = true;
				vol.mute = true;
				expect(vol.mute).to.be.true;
				expect(vol.volume.value).to.equal(-Infinity);
				vol.mute = false;
				vol.mute = false;
				expect(vol.volume.value).to.be.closeTo(-20, 0.5);
				vol.dispose();
			});

		});
	});
});