component-emitter - npm Package Compare versions

Comparing version 1.3.1 to 2.0.0

index.js

@@ -0,175 +1,106 @@
+function Emitter(object) {
+	if (object) {
+		return mixin(object);
+	}
 
-/**
- * Expose `Emitter`.
- */
-
-if (typeof module !== 'undefined') {
-  module.exports = Emitter;
+	this._callbacks = new Map();
 }
 
-/**
- * Initialize a new `Emitter`.
- *
- * @api public
- */
-
-function Emitter(obj) {
-  if (obj) return mixin(obj);
-};
-
-/**
- * Mixin the emitter properties.
- *
- * @param {Object} obj
- * @return {Object}
- * @api private
- */
-
-function mixin(obj) {
-  for (var key in Emitter.prototype) {
-    obj[key] = Emitter.prototype[key];
-  }
-  return obj;
+function mixin(object) {
+	Object.assign(object, Emitter.prototype);
+	object._callbacks = new Map();
+	return object;
 }
 
-/**
- * Listen on the given `event` with `fn`.
- *
- * @param {String} event
- * @param {Function} fn
- * @return {Emitter}
- * @api public
- */
-
-Emitter.prototype.on =
-Emitter.prototype.addEventListener = function(event, fn){
-  this._callbacks = this._callbacks || {};
-  (this._callbacks['$' + event] = this._callbacks['$' + event] || [])
-    .push(fn);
-  return this;
+Emitter.prototype.on = function (event, listener) {
+	const callbacks = this._callbacks.get(event) ?? [];
+	callbacks.push(listener);
+	this._callbacks.set(event, callbacks);
+	return this;
 };
 
-/**
- * Adds an `event` listener that will be invoked a single
- * time then automatically removed.
- *
- * @param {String} event
- * @param {Function} fn
- * @return {Emitter}
- * @api public
- */
+Emitter.prototype.once = function (event, listener) {
+	const on = (...arguments_) => {
+		this.off(event, on);
+		listener.apply(this, arguments_);
+	};
 
-Emitter.prototype.once = function(event, fn){
-  function on() {
-    this.off(event, on);
-    fn.apply(this, arguments);
-  }
-
-  on.fn = fn;
-  this.on(event, on);
-  return this;
+	on.fn = listener;
+	this.on(event, on);
+	return this;
 };
 
-/**
- * Remove the given callback for `event` or all
- * registered callbacks.
- *
- * @param {String} event
- * @param {Function} fn
- * @return {Emitter}
- * @api public
- */
+Emitter.prototype.off = function (event, listener) {
+	if (event === undefined && listener === undefined) {
+		this._callbacks.clear();
+		return this;
+	}
 
-Emitter.prototype.off =
-Emitter.prototype.removeListener =
-Emitter.prototype.removeAllListeners =
-Emitter.prototype.removeEventListener = function(event, fn){
-  this._callbacks = this._callbacks || {};
+	if (listener === undefined) {
+		this._callbacks.delete(event);
+		return this;
+	}
 
-  // all
-  if (0 == arguments.length) {
-    this._callbacks = {};
-    return this;
-  }
+	const callbacks = this._callbacks.get(event);
+	if (callbacks) {
+		for (const [index, callback] of callbacks.entries()) {
+			if (callback === listener || callback.fn === listener) {
+				callbacks.splice(index, 1);
+				break;
+			}
+		}
 
-  // specific event
-  var callbacks = this._callbacks['$' + event];
-  if (!callbacks) return this;
+		if (callbacks.length === 0) {
+			this._callbacks.delete(event);
+		} else {
+			this._callbacks.set(event, callbacks);
+		}
+	}
 
-  // remove all handlers
-  if (1 == arguments.length) {
-    delete this._callbacks['$' + event];
-    return this;
-  }
+	return this;
+};
 
-  // remove specific handler
-  var cb;
-  for (var i = 0; i < callbacks.length; i++) {
-    cb = callbacks[i];
-    if (cb === fn || cb.fn === fn) {
-      callbacks.splice(i, 1);
-      break;
-    }
-  }
+Emitter.prototype.emit = function (event, ...arguments_) {
+	const callbacks = this._callbacks.get(event);
+	if (callbacks) {
+		// Create a copy of the callbacks array to avoid issues if it's modified during iteration
+		const callbacksCopy = [...callbacks];
 
-  // Remove event specific arrays for event types that no
-  // one is subscribed for to avoid memory leak.
-  if (callbacks.length === 0) {
-    delete this._callbacks['$' + event];
-  }
+		for (const callback of callbacksCopy) {
+			callback.apply(this, arguments_);
+		}
+	}
 
-  return this;
+	return this;
 };
 
-/**
- * Emit `event` with the given args.
- *
- * @param {String} event
- * @param {Mixed} ...
- * @return {Emitter}
- */
+Emitter.prototype.listeners = function (event) {
+	return this._callbacks.get(event) ?? [];
+};
 
-Emitter.prototype.emit = function(event){
-  this._callbacks = this._callbacks || {};
+Emitter.prototype.listenerCount = function (event) {
+	if (event) {
+		return this.listeners(event).length;
+	}
 
-  var args = new Array(arguments.length - 1)
-    , callbacks = this._callbacks['$' + event];
+	let totalCount = 0;
+	for (const callbacks of this._callbacks.values()) {
+		totalCount += callbacks.length;
+	}
 
-  for (var i = 1; i < arguments.length; i++) {
-    args[i - 1] = arguments[i];
-  }
-
-  if (callbacks) {
-    callbacks = callbacks.slice(0);
-    for (var i = 0, len = callbacks.length; i < len; ++i) {
-      callbacks[i].apply(this, args);
-    }
-  }
-
-  return this;
+	return totalCount;
 };
 
-/**
- * Return array of callbacks for `event`.
- *
- * @param {String} event
- * @return {Array}
- * @api public
- */
-
-Emitter.prototype.listeners = function(event){
-  this._callbacks = this._callbacks || {};
-  return this._callbacks['$' + event] || [];
+Emitter.prototype.hasListeners = function (event) {
+	return this.listenerCount(event) > 0;
 };
 
-/**
- * Check if this emitter has `event` handlers.
- *
- * @param {String} event
- * @return {Boolean}
- * @api public
- */
+// Aliases
+Emitter.prototype.addEventListener = Emitter.prototype.on;
+Emitter.prototype.removeListener = Emitter.prototype.off;
+Emitter.prototype.removeEventListener = Emitter.prototype.off;
+Emitter.prototype.removeAllListeners = Emitter.prototype.off;
 
-Emitter.prototype.hasListeners = function(event){
-  return !! this.listeners(event).length;
-};
+if (typeof module !== 'undefined') {
+	module.exports = Emitter;
+}

package.json

 {
-  "name": "component-emitter",
-  "description": "Event emitter",
-  "version": "1.3.1",
-  "license": "MIT",
-  "funding": "https://github.com/sponsors/sindresorhus",
-  "devDependencies": {
-    "mocha": "*",
-    "should": "*"
-  },
-  "component": {
-    "scripts": {
-      "emitter/index.js": "index.js"
-    }
-  },
-  "main": "index.js",
-  "repository": {
-    "type": "git",
-    "url": "https://github.com/sindresorhus/component-emitter.git"
-  },
-  "scripts": {
-    "test": "make test"
-  },
-  "files": [
-    "index.js",
-    "LICENSE"
-  ]
+	"name": "component-emitter",
+	"version": "2.0.0",
+	"description": "Simple event emitter",
+	"license": "MIT",
+	"repository": "sindresorhus/component-emitter",
+	"funding": "https://github.com/sponsors/sindresorhus",
+	"exports": {
+		"types": "./index.d.ts",
+		"default": "./index.js"
+	},
+	"main": "./index.js",
+	"types": "./index.d.ts",
+	"sideEffects": false,
+	"engines": {
+		"node": ">=18"
+	},
+	"scripts": {
+		"test": "xo && ava"
+	},
+	"files": [
+		"index.js",
+		"index.d.ts"
+	],
+	"keywords": [
+		"event",
+		"emitter",
+		"events",
+		"emit",
+		"listener",
+		"pubsub",
+		"observe"
+	],
+	"devDependencies": {
+		"ava": "^5.3.1",
+		"xo": "^0.56.0"
+	},
+	"xo": {
+		"rules": {
+			"unicorn/prefer-module": "off"
+		}
+	}
 }

New alerts

Major refactor

Supply chain risk

Package has recently undergone a major refactor. It may be unstable or indicate significant internal changes. Use caution when updating to versions that include significant changes.

Found 1 instance in 1 package

Fixed alerts

New author

Supply chain risk

A new npm collaborator published a version of the package for the first time. New collaborators are usually benign additions to a project, but do indicate a change to the security surface area of a package.

Found 1 instance in 1 package

Improved metrics

Total package byte prevSize

9568

increased by51.75%

Number of package files

5

increased by25%

Lines of code

182

increased by24.66%

Number of lines in readme file

101

increased by34.67%

No dependency changes