add fft tests for smoothing and bins (#185)

src/fft.js

@@ -99,34 +99,34 @@ define(function (require) {
           return this.analyser.fftSize / 2;
         },
         set: function(b) {
-          this.analyser.fftSize = (b * 2) || 1024;
+          this.analyser.fftSize = (b * 2);
         },
         configurable: true,
         enumerable: true
       },
       'smoothing': {
         get: function() {
-          return this.analyser.smoothing;
+          return this.analyser.smoothingTimeConstant;
         },
         set: function(s) {
-          this.analyser.smoothingTimeConstant = s || 0.8;
+          this.analyser.smoothingTimeConstant = s;
         },
         configurable: true,
         enumerable: true
       }
     });
-    
-    //
-    this.smoothing = smoothing;
-    this.bins = bins;
+
+    // set default smoothing and bins
+    this.smooth(smoothing);
+    this.bins = bins || 1024;
 
     // default connections to p5sound fftMeter
     p5sound.fftMeter.connect(this.analyser);
 
     this.freqDomain = new Uint8Array(this.analyser.frequencyBinCount);
     this.timeDomain = new Uint8Array(this.analyser.frequencyBinCount);
 
-    // predefined frequency ranages, these will be tweakable
+    // predefined frequency ranges, these will be tweakable
     this.bass = [20, 140];
     this.lowMid = [140, 400];
     this.mid = [400, 2600];
@@ -488,10 +488,10 @@ define(function (require) {
    *                               Defaults to 0.8.
    */
   p5.FFT.prototype.smooth = function(s) {
-    if (s) {
+    if (typeof s !== 'undefined') {
       this.smoothing = s;
     }
-    this.analyser.smoothingTimeConstant = s;
+    return this.smoothing;
   };
 
   p5.FFT.prototype.dispose = function() {

test/test.js

@@ -2,13 +2,13 @@ require.config({
 	baseUrl:'./',
 	paths : {
 		'lib' : '../lib',
-		'chai' : './testDeps/chai',
+		'chai' : './testDeps/chai'
 	}
 });
 
 var allTests = ['tests/p5.SoundFile', 'tests/p5.Amplitude', 
 	'tests/p5.Oscillator', 'tests/p5.Distortion', 
-	'tests/p5.Effect','tests/p5.Filter'];
+	'tests/p5.Effect','tests/p5.Filter', 'tests/p5.FFT'];
 
 p5.prototype.masterVolume(0);
 

test/tests/p5.FFT.js

@@ -0,0 +1,62 @@
+define(['chai'],
+  function(chai) {
+
+  var expect = chai.expect;
+
+  describe('p5.FFT', function() {
+    var fft;
+
+    beforeEach(function() {
+      fft = new p5.FFT();
+    });
+
+    afterEach(function() {
+      fft.dispose();
+    });
+
+    it('has default bins of 1024', function() {
+      expect(fft.bins).to.equal(1024);
+    });
+
+    it('has default smoothing of 0.8', function() {
+      expect(fft.smooth()).to.equal(0.8);
+      expect(fft.smoothing).to.equal(0.8);
+    });
+
+    it('accepts smoothing and bins as args', function() {
+      fft.dispose();
+      fft = new p5.FFT(0, 128);
+      expect(fft.smoothing).to.equal(0);
+      expect(fft.bins).to.equal(128);
+    });
+
+    it('can set smoothing to zero', function() {
+      fft.smooth(0);
+      expect(fft.smoothing).to.equal(0);
+      expect(fft.smooth()).to.equal(0);
+      fft.smooth(0.9);
+      expect(fft.smoothing).to.equal(0.9);
+      expect(fft.smooth()).to.equal(0.9);
+    });
+
+    it('handles smoothing values out of range', function() {
+      expect(fft.smooth()).to.equal(0.8);
+      try {
+        fft.smooth(-1);
+        expect.fail();
+      } catch(e) {
+        expect(e).to.be.an.instanceof(Error);
+      }
+      expect(fft.smoothing).to.equal(0.8);
+      expect(fft.smooth()).to.equal(0.8);
+      try {
+        fft.smooth('some bad param');
+        expect.fail();
+      } catch(e) {
+        expect(e).to.be.an.instanceof(Error);
+      }
+      expect(fft.smoothing).to.equal(0.8);
+      expect(fft.smooth()).to.equal(0.8);
+    });
+  });
+});