added removeListener event #6

Author: sokra

lib/events.js

@@ -164,25 +164,69 @@ EventEmitter.prototype.removeListener = function(type, listener) {
     delete this._events[type];
   }
 
+  if (this._events.removeListener)
+    this.emit('removeListener', type, listener);
   return this;
 };
 
 EventEmitter.prototype.removeAllListeners = function(type) {
+  var key, listeners;
+
+  if (!this._events)
+    return this;
+
+  // not listening for removeListener, no need to emit
+  if (!this._events.removeListener) {
+    if (arguments.length === 0)
+      this._events = {};
+    else if (this._events[type])
+      this._events[type] = undefined;
+    return this;
+  }
+
+  // emit removeListener for all listeners on all events
   if (arguments.length === 0) {
+    for (key in this._events) {
+      if (key === 'removeListener') continue;
+      this.removeAllListeners(key);
+    }
+    this.removeAllListeners('removeListener');
     this._events = {};
     return this;
   }
 
-  // does not use listeners(), so no side effect of creating _events[type]
-  if (type && this._events && this._events[type]) this._events[type] = null;
+  listeners = this._events[type];
+
+  if (typeof listeners === 'function') {
+    this.removeListener(type, listeners);
+  } else {
+    // LIFO order
+    while (listeners.length)
+      this.removeListener(type, listeners[listeners.length - 1]);
+  }
+  this._events[type] = undefined;
+
   return this;
 };
 
 EventEmitter.prototype.listeners = function(type) {
-  if (!this._events) this._events = {};
-  if (!this._events[type]) this._events[type] = [];
-  if (!isArray(this._events[type])) {
-    this._events[type] = [this._events[type]];
-  }
-  return this._events[type];
+  var ret;
+  if (!this._events || !this._events[type])
+    ret = [];
+  else if (typeof this._events[type] === 'function')
+    ret = [this._events[type]];
+  else
+    ret = this._events[type].slice();
+  return ret;
 };
+
+EventEmitter.listenerCount = function(emitter, type) {
+  var ret;
+  if (!emitter._events || !emitter._events[type])
+    ret = 0;
+  else if (typeof emitter._events[type] === 'function')
+    ret = 1;
+  else
+    ret = emitter._events[type].length;
+  return ret;
+};

test/events.js

@@ -259,7 +259,7 @@ test('remove all listeners', function() {
 	assert.deepEqual([], e2.listeners('bar'));
 });
 
-test('remove listener', function() {
+test('remove listener', function(done) {
 	var count = 0;
 
 	function listener1() {
@@ -289,6 +289,24 @@ test('remove listener', function() {
 	e3.on('hello', listener2);
 	e3.removeListener('hello', listener1);
 	assert.deepEqual([listener2], e3.listeners('hello'));
+
+	done = after(2, done);
+	function remove1() {
+		assert(0);
+	}
+	function remove2() {
+		assert(0);
+	}
+	var e4 = new events.EventEmitter();
+	e4.on('removeListener', function(name, cb) {
+		if (cb !== remove1) return done();
+		this.removeListener('quux', remove2);
+	    this.emit('quux');
+		done();
+	});
+	e4.on('quux', remove1);
+	e4.on('quux', remove2);
+	e4.removeListener('quux', remove1);
 });
 
 test('subclass', function(done) {