Added check for valid callback function in Peaks.init()

See #546

Author: chrisn

src/main.js

@@ -337,6 +337,7 @@ function checkContainerElements(options) {
  * Creates and initialises a new Peaks instance with the given options.
  *
  * @param {Object} opts Configuration options
+ * @param {Function} callback
  *
  * @return {Peaks}
  */
@@ -346,6 +347,10 @@ Peaks.init = function(opts, callback) {
 
   let err = instance._setOptions(opts);
 
+  if (!callback) {
+    instance._logger('Peaks.init(): Missing callback function');
+  }
+
   if (!err) {
     err = checkContainerElements(instance.options);
   }
@@ -448,7 +453,9 @@ Peaks.init = function(opts, callback) {
           instance.emit('peaks.ready');
         }, 0);
 
-        callback(null, instance);
+        if (callback) {
+          callback(null, instance);
+        }
       });
     })
     .catch(function(err) {
@@ -608,6 +615,14 @@ Peaks.prototype.getWaveformData = function() {
   return this._waveformData;
 };
 
+Peaks.prototype.on = function(type, listener, options) {
+  if (type === 'peaks.ready') {
+    this._logger('Peaks.on(): The peaks.ready event is deprecated');
+  }
+
+  EventEmitter.prototype.on.call(this, type, listener, options);
+};
+
 /**
  * Cleans up a Peaks instance after use.
  */

test/api-spec.js

@@ -74,6 +74,8 @@ describe('Peaks', function() {
       });
 
       it('should emit a peaks.ready event when initialised', function(done) {
+        const logger = sinon.spy();
+
         Peaks.init({
           overview: {
             container: document.getElementById('overview-container')
@@ -82,19 +84,49 @@ describe('Peaks', function() {
             container: document.getElementById('zoomview-container')
           },
           mediaElement: document.getElementById('media'),
-          dataUri: { arraybuffer: '/base/test/data/sample.dat' }
+          dataUri: { arraybuffer: '/base/test/data/sample.dat' },
+          logger: logger
         },
         function(err, instance) {
           expect(err).to.equal(null);
           expect(instance).to.be.an.instanceOf(Peaks);
 
           instance.on('peaks.ready', function() {
+            expect(logger.callCount).to.equal(1);
+            expect(logger).calledWithMatch(/deprecated/);
             expect(instance.getWaveformData()).to.be.an.instanceOf(WaveformData);
             done();
           });
         });
       });
 
+      it('should emit a peaks.ready event when initialised without a callback', function(done) {
+        const logger = sinon.spy();
+
+        const instance = Peaks.init({
+          overview: {
+            container: document.getElementById('overview-container')
+          },
+          zoomview: {
+            container: document.getElementById('zoomview-container')
+          },
+          mediaElement: document.getElementById('media'),
+          dataUri: { arraybuffer: '/base/test/data/sample.dat' },
+          logger: logger
+        });
+
+        expect(instance).to.be.an.instanceOf(Peaks);
+
+        expect(logger.callCount).to.equal(1);
+
+        instance.on('peaks.ready', function() {
+          expect(logger.callCount).to.equal(2);
+          expect(logger.getCall(0).args[0]).to.match(/callback/);
+          expect(logger.getCall(1).args[0]).to.match(/deprecated/);
+          done();
+        });
+      });
+
       context('with zoomview and overview options', function() {
         it('should construct a Peaks object with overview and zoomable waveforms', function(done) {
           Peaks.init({