eventemitter3 - npm Package Compare versions

Comparing version 1.2.0 to 2.0.0

index.js

 'use strict';
 
-var has = Object.prototype.hasOwnProperty;
+var has = Object.prototype.hasOwnProperty
+  , prefix = '~';
 
+/**
+ * Constructor to create a storage for our `EE` objects.
+ * An `Events` instance is a plain object whose properties are event names.
+ *
+ * @constructor
+ * @api private
+ */
+function Events() {}
+
 //
-// We store our EE objects in a plain object whose properties are event names.
+// We try to not inherit from `Object.prototype`. In some engines creating an
+// instance in this way is faster than calling `Object.create(null)` directly.
 // If `Object.create(null)` is not supported we prefix the event names with a
-// `~` to make sure that the built-in object properties are not overridden or
-// used as an attack vector.
-// We also assume that `Object.create(null)` is available when the event name
-// is an ES6 Symbol.
+// character to make sure that the built-in object properties are not
+// overridden or used as an attack vector.
 //
-var prefix = typeof Object.create !== 'function' ? '~' : false;
+if (Object.create) {
+  Events.prototype = Object.create(null);
 
+  //
+  // This hack is needed because the `__proto__` property is still inherited in
+  // some old browsers like Android 4, iPhone 5.1, Opera 11 and Safari 5.
+  //
+  if (!new Events().__proto__) prefix = false;
+}
+
 /**
- * Representation of a single EventEmitter function.
+ * Representation of a single event listener.
  *
- * @param {Function} fn Event handler to be called.
- * @param {Mixed} context Context for function execution.
- * @param {Boolean} [once=false] Only emit once
+ * @param {Function} fn The listener function.
+ * @param {Mixed} context The context to invoke the listener with.
+ * @param {Boolean} [once=false] Specify if the listener is a one-time listener.
+ * @constructor
  * @api private
@@ -30,4 +48,4 @@ */
 /**
- * Minimal EventEmitter interface that is molded against the Node.js
- * EventEmitter interface.
+ * Minimal `EventEmitter` interface that is molded against the Node.js
+ * `EventEmitter` interface.
  *
@@ -37,13 +55,8 @@ * @constructor
  */
-function EventEmitter() { /* Nothing to set */ }
+function EventEmitter() {
+  this._events = new Events();
+  this._eventsCount = 0;
+}
 
 /**
- * Hold the assigned EventEmitters by name.
- *
- * @type {Object}
- * @private
- */
-EventEmitter.prototype._events = undefined;
-
-/**
  * Return an array listing the events for which the emitter has registered
@@ -56,9 +69,9 @@ * listeners.
 EventEmitter.prototype.eventNames = function eventNames() {
-  var events = this._events
-    , names = []
+  var names = []
+    , events
     , name;
 
-  if (!events) return names;
+  if (this._eventsCount === 0) return names;
 
-  for (name in events) {
+  for (name in (events = this._events)) {
     if (has.call(events, name)) names.push(prefix ? name.slice(1) : name);
@@ -75,6 +88,6 @@ }
 /**
- * Return a list of assigned event listeners.
+ * Return the listeners registered for a given event.
  *
- * @param {String} event The events that should be listed.
- * @param {Boolean} exists We only need to know if there are listeners.
+ * @param {String|Symbol} event The event name.
+ * @param {Boolean} exists Only check if there are listeners.
  * @returns {Array|Boolean}
@@ -85,3 +98,3 @@ * @api public
   var evt = prefix ? prefix + event : event
-    , available = this._events && this._events[evt];
+    , available = this._events[evt];
 
@@ -100,6 +113,6 @@ if (exists) return !!available;
 /**
- * Emit an event to all registered event listeners.
+ * Calls each of the listeners registered for a given event.
  *
- * @param {String} event The name of the event.
- * @returns {Boolean} Indication if we've emitted an event.
+ * @param {String|Symbol} event The event name.
+ * @returns {Boolean} `true` if the event had listeners, else `false`.
  * @api public
@@ -110,3 +123,3 @@ */
 
-  if (!this._events || !this._events[evt]) return false;
+  if (!this._events[evt]) return false;
 
@@ -118,3 +131,3 @@ var listeners = this._events[evt]
 
-  if ('function' === typeof listeners.fn) {
+  if (listeners.fn) {
     if (listeners.once) this.removeListener(event, listeners.fn, undefined, true);
@@ -147,2 +160,3 @@
         case 3: listeners[i].fn.call(listeners[i].context, a1, a2); break;
+        case 4: listeners[i].fn.call(listeners[i].context, a1, a2, a3); break;
         default:
@@ -162,7 +176,8 @@ if (!args) for (j = 1, args = new Array(len -1); j < len; j++) {
 /**
- * Register a new EventListener for the given event.
+ * Add a listener for a given event.
  *
- * @param {String} event Name of the event.
- * @param {Function} fn Callback function.
- * @param {Mixed} [context=this] The context of the function.
+ * @param {String|Symbol} event The event name.
+ * @param {Function} fn The listener function.
+ * @param {Mixed} [context=this] The context to invoke the listener with.
+ * @returns {EventEmitter} `this`.
  * @api public
@@ -174,10 +189,5 @@ */
 
-  if (!this._events) this._events = prefix ? {} : Object.create(null);
-  if (!this._events[evt]) this._events[evt] = listener;
-  else {
-    if (!this._events[evt].fn) this._events[evt].push(listener);
-    else this._events[evt] = [
-      this._events[evt], listener
-    ];
-  }
+  if (!this._events[evt]) this._events[evt] = listener, this._eventsCount++;
+  else if (!this._events[evt].fn) this._events[evt].push(listener);
+  else this._events[evt] = [this._events[evt], listener];
 
@@ -188,7 +198,8 @@ return this;
 /**
- * Add an EventListener that's only called once.
+ * Add a one-time listener for a given event.
  *
- * @param {String} event Name of the event.
- * @param {Function} fn Callback function.
- * @param {Mixed} [context=this] The context of the function.
+ * @param {String|Symbol} event The event name.
+ * @param {Function} fn The listener function.
+ * @param {Mixed} [context=this] The context to invoke the listener with.
+ * @returns {EventEmitter} `this`.
  * @api public
@@ -200,10 +211,5 @@ */
 
-  if (!this._events) this._events = prefix ? {} : Object.create(null);
-  if (!this._events[evt]) this._events[evt] = listener;
-  else {
-    if (!this._events[evt].fn) this._events[evt].push(listener);
-    else this._events[evt] = [
-      this._events[evt], listener
-    ];
-  }
+  if (!this._events[evt]) this._events[evt] = listener, this._eventsCount++;
+  else if (!this._events[evt].fn) this._events[evt].push(listener);
+  else this._events[evt] = [this._events[evt], listener];
 
@@ -214,8 +220,9 @@ return this;
 /**
- * Remove event listeners.
+ * Remove the listeners of a given event.
  *
- * @param {String} event The event we want to remove.
- * @param {Function} fn The listener that we need to find.
- * @param {Mixed} context Only remove listeners matching this context.
- * @param {Boolean} once Only remove once listeners.
+ * @param {String|Symbol} event The event name.
+ * @param {Function} fn Only remove the listeners that match this function.
+ * @param {Mixed} context Only remove the listeners that have this context.
+ * @param {Boolean} once Only remove one-time listeners.
+ * @returns {EventEmitter} `this`.
  * @api public
@@ -226,36 +233,37 @@ */
 
-  if (!this._events || !this._events[evt]) return this;
+  if (!this._events[evt]) return this;
+  if (!fn) {
+    if (--this._eventsCount === 0) this._events = new Events();
+    else delete this._events[evt];
+    return this;
+  }
 
-  var listeners = this._events[evt]
-    , events = [];
+  var listeners = this._events[evt];
 
-  if (fn) {
-    if (listeners.fn) {
+  if (listeners.fn) {
+    if (
+         listeners.fn === fn
+      && (!once || listeners.once)
+      && (!context || listeners.context === context)
+    ) {
+      if (--this._eventsCount === 0) this._events = new Events();
+      else delete this._events[evt];
+    }
+  } else {
+    for (var i = 0, events = [], length = listeners.length; i < length; i++) {
       if (
-           listeners.fn !== fn
-        || (once && !listeners.once)
-        || (context && listeners.context !== context)
+           listeners[i].fn !== fn
+        || (once && !listeners[i].once)
+        || (context && listeners[i].context !== context)
       ) {
-        events.push(listeners);
+        events.push(listeners[i]);
       }
-    } else {
-      for (var i = 0, length = listeners.length; i < length; i++) {
-        if (
-             listeners[i].fn !== fn
-          || (once && !listeners[i].once)
-          || (context && listeners[i].context !== context)
-        ) {
-          events.push(listeners[i]);
-        }
-      }
     }
-  }
 
-  //
-  // Reset the array, or remove it completely if we have no more listeners.
-  //
-  if (events.length) {
-    this._events[evt] = events.length === 1 ? events[0] : events;
-  } else {
-    delete this._events[evt];
+    //
+    // Reset the array, or remove it completely if we have no more listeners.
+    //
+    if (events.length) this._events[evt] = events.length === 1 ? events[0] : events;
+    else if (--this._eventsCount === 0) this._events = new Events();
+    else delete this._events[evt];
   }
@@ -267,12 +275,21 @@
 /**
- * Remove all listeners or only the listeners for the specified event.
+ * Remove all listeners, or those of the specified event.
  *
- * @param {String} event The event want to remove all listeners for.
+ * @param {String|Symbol} [event] The event name.
+ * @returns {EventEmitter} `this`.
  * @api public
  */
 EventEmitter.prototype.removeAllListeners = function removeAllListeners(event) {
-  if (!this._events) return this;
+  var evt;
 
-  if (event) delete this._events[prefix ? prefix + event : event];
-  else this._events = prefix ? {} : Object.create(null);
+  if (event) {
+    evt = prefix ? prefix + event : event;
+    if (this._events[evt]) {
+      if (--this._eventsCount === 0) this._events = new Events();
+      else delete this._events[evt];
+    }
+  } else {
+    this._events = new Events();
+    this._eventsCount = 0;
+  }
 
@@ -279,0 +296,0 @@ return this;

package.json

 {
   "name": "eventemitter3",
-  "version": "1.2.0",
+  "version": "2.0.0",
   "description": "EventEmitter3 focuses on performance while maintaining a Node.js AND browser compatible interface.",
   "main": "index.js",
   "scripts": {
+    "benchmark": "find benchmarks/run -name '*.js' -exec benchmarks/start.sh {} \\;",
     "test-node": "istanbul cover _mocha --report lcovonly -- test.js",
@@ -41,8 +42,8 @@ "coverage": "istanbul cover _mocha -- test.js",
   "devDependencies": {
-    "assume": "1.3.x",
+    "assume": "1.4.x",
     "istanbul": "0.4.x",
-    "mocha": "2.4.x",
+    "mocha": "3.0.x",
     "pre-commit": "1.1.x",
-    "zuul": "3.10.x"
+    "zuul": "3.11.x"
   }
 }

README.md

 # EventEmitter3
 
-[![Version npm](https://img.shields.io/npm/v/eventemitter3.svg?style=flat-square)](http://browsenpm.org/package/eventemitter3)[![Build Status](https://img.shields.io/travis/primus/eventemitter3/master.svg?style=flat-square)](https://travis-ci.org/primus/eventemitter3)[![Dependencies](https://img.shields.io/david/primus/eventemitter3.svg?style=flat-square)](https://david-dm.org/primus/eventemitter3)[![Coverage Status](https://img.shields.io/coveralls/primus/eventemitter3/master.svg?style=flat-square)](https://coveralls.io/r/primus/eventemitter3?branch=master)[![IRC channel](https://img.shields.io/badge/IRC-irc.freenode.net%23primus-00a8ff.svg?style=flat-square)](https://webchat.freenode.net/?channels=primus)
+[![Version npm](https://img.shields.io/npm/v/eventemitter3.svg?style=flat-square)](https://www.npmjs.com/package/eventemitter3)[![Build Status](https://img.shields.io/travis/primus/eventemitter3/master.svg?style=flat-square)](https://travis-ci.org/primus/eventemitter3)[![Dependencies](https://img.shields.io/david/primus/eventemitter3.svg?style=flat-square)](https://david-dm.org/primus/eventemitter3)[![Coverage Status](https://img.shields.io/coveralls/primus/eventemitter3/master.svg?style=flat-square)](https://coveralls.io/r/primus/eventemitter3?branch=master)[![IRC channel](https://img.shields.io/badge/IRC-irc.freenode.net%23primus-00a8ff.svg?style=flat-square)](https://webchat.freenode.net/?channels=primus)
 
@@ -18,7 +18,10 @@ [![Sauce Test Status](https://saucelabs.com/browser-matrix/eventemitter3.svg)](https://saucelabs.com/u/eventemitter3)
   really just edge cases.
-- No `setMaxListeners` and it's pointless memory leak warnings. If you want to
+- No `setMaxListeners` and its pointless memory leak warnings. If you want to
   add `end` listeners you should be able to do that without modules complaining.
-- No `listenerCount` function. Use `EE.listeners(event).length` instead.
+- No `listenerCount` method. Use `EE.listeners(event).length` instead.
 - Support for custom context for events so there is no need to use `fn.bind`.
-- `listeners` method can do existence checking instead of returning only arrays.
+- The `listeners` method can do existence checking instead of returning only
+  arrays.
+- The `removeListener` method removes all matching listeners, not only the
+  first.
 
@@ -88,4 +91,18 @@ It's a drop in replacement for existing EventEmitters, but just faster. Free
 
+### Tests and benchmarks
+
+This module is well tested. You can run:
+
+- `npm test` to run the tests under Node.js.
+- `npm run coverage` to get the code coverage.
+- `npm run test-browser` to run the tests in real browsers via Sauce Labs.
+
+We also have a set of benchmarks to compare EventEmitter3 with some available
+alternatives. To run the benchmarks run `npm run benchmark`.
+
+Tests and benchmarks are not included in the npm package. If you want to play
+with them you have to clone the GitHub repository.
+
 ## License
 
 [MIT](LICENSE)

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Improved metrics

Total package byte prevSize

15048

increased by10.49%

Lines of code

261

increased by6.53%

Number of lines in readme file

107

increased by18.89%

No dependency changes