axmol/cocos/scripting/js-bindings/script/debugger/event-emitter.js

/****************************************************************************
 Copyright (c) 2017-2018 Xiamen Yaji Software Co., Ltd.
 
 http://www.cocos2d-x.org
 
 Permission is hereby granted, free of charge, to any person obtaining a copy
 of this software and associated documentation files (the "Software"), to deal
 in the Software without restriction, including without limitation the rights
 to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
 copies of the Software, and to permit persons to whom the Software is
 furnished to do so, subject to the following conditions:
 
 The above copyright notice and this permission notice shall be included in
 all copies or substantial portions of the Software.
 
 THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
 AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
 OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
 THE SOFTWARE.
 ****************************************************************************/

/* This Source Code Form is subject to the terms of the Mozilla Public
 * License, v. 2.0. If a copy of the MPL was not distributed with this
 * file, You can obtain one at http://mozilla.org/MPL/2.0/. */

/**
 * EventEmitter.
 */

// (function (factory) { // Module boilerplate
//   if (this.module && module.id.indexOf("event-emitter") >= 0) { // require
//     factory.call(this, require, exports, module);
//   } else { // Cu.import
//       const Cu = Components.utils;
//       const { require } = Cu.import("resource://gre/modules/devtools/Loader.jsm", {});
//       this.isWorker = false;
//       this.promise = Cu.import("resource://gre/modules/Promise.jsm", {}).Promise;
//       factory.call(this, require, this, { exports: this });
//       this.EXPORTED_SYMBOLS = ["EventEmitter"];
//   }
// }).call(this, function (require, exports, module) {

this.EventEmitter = function EventEmitter() {};
// module.exports = EventEmitter;

// const { Cu, components } = require("chrome");
// const Services = require("Services");
// const promise = require("promise");
var loggingEnabled = true;

// if (!isWorker) {
//   loggingEnabled = Services.prefs.getBoolPref("devtools.dump.emit");
//   Services.prefs.addObserver("devtools.dump.emit", {
//     observe: () => {
//       loggingEnabled = Services.prefs.getBoolPref("devtools.dump.emit");
//     }
//   }, false);
// }

/**
 * Decorate an object with event emitter functionality.
 *
 * @param Object aObjectToDecorate
 *        Bind all public methods of EventEmitter to
 *        the aObjectToDecorate object.
 */
EventEmitter.decorate = function EventEmitter_decorate (aObjectToDecorate) {
  let emitter = new EventEmitter();
  aObjectToDecorate.on = emitter.on.bind(emitter);
  aObjectToDecorate.off = emitter.off.bind(emitter);
  aObjectToDecorate.once = emitter.once.bind(emitter);
  aObjectToDecorate.emit = emitter.emit.bind(emitter);
};

EventEmitter.prototype = {
  /**
   * Connect a listener.
   *
   * @param string aEvent
   *        The event name to which we're connecting.
   * @param function aListener
   *        Called when the event is fired.
   */
  on: function EventEmitter_on(aEvent, aListener) {
    if (!this._eventEmitterListeners)
      this._eventEmitterListeners = new Map();
    if (!this._eventEmitterListeners.has(aEvent)) {
      this._eventEmitterListeners.set(aEvent, []);
    }
    this._eventEmitterListeners.get(aEvent).push(aListener);
  },

  /**
   * Listen for the next time an event is fired.
   *
   * @param string aEvent
   *        The event name to which we're connecting.
   * @param function aListener
   *        (Optional) Called when the event is fired. Will be called at most
   *        one time.
   * @return promise
   *        A promise which is resolved when the event next happens. The
   *        resolution value of the promise is the first event argument. If
   *        you need access to second or subsequent event arguments (it's rare
   *        that this is needed) then use aListener
   */
  once: function EventEmitter_once(aEvent, aListener) {
    let deferred = promise.defer();

    let handler = (aEvent, aFirstArg, ...aRest) => {
      this.off(aEvent, handler);
      if (aListener) {
        aListener.apply(null, [aEvent, aFirstArg, ...aRest]);
      }
      deferred.resolve(aFirstArg);
    };

    handler._originalListener = aListener;
    this.on(aEvent, handler);

    return deferred.promise;
  },

  /**
   * Remove a previously-registered event listener.  Works for events
   * registered with either on or once.
   *
   * @param string aEvent
   *        The event name whose listener we're disconnecting.
   * @param function aListener
   *        The listener to remove.
   */
  off: function EventEmitter_off(aEvent, aListener) {
    if (!this._eventEmitterListeners)
      return;
    let listeners = this._eventEmitterListeners.get(aEvent);
    if (listeners) {
      this._eventEmitterListeners.set(aEvent, listeners.filter(l => {
        return l !== aListener && l._originalListener !== aListener;
      }));
    }
  },

  /**
   * Emit an event.  All arguments to this method will
   * be sent to listener functions.
   */
  emit: function EventEmitter_emit(aEvent) {
    this.logEvent(aEvent, arguments);

    if (!this._eventEmitterListeners || !this._eventEmitterListeners.has(aEvent)) {
      return;
    }

    let originalListeners = this._eventEmitterListeners.get(aEvent);
    for (let listener of this._eventEmitterListeners.get(aEvent)) {
      // If the object was destroyed during event emission, stop
      // emitting.
      if (!this._eventEmitterListeners) {
        break;
      }

      // If listeners were removed during emission, make sure the
      // event handler we're going to fire wasn't removed.
      if (originalListeners === this._eventEmitterListeners.get(aEvent) ||
          this._eventEmitterListeners.get(aEvent).some(l => l === listener)) {
        try {
          listener.apply(null, arguments);
        }
        catch (ex) {
          // Prevent a bad listener from interfering with the others.
          let msg = ex + ": " + ex.stack;
          Cu.reportError(msg);
          dump(msg + "\n");
        }
      }
    }
  },

  logEvent: function(aEvent, args) {
    if (!loggingEnabled) {
      return;
    }

    let caller, func, path;
    if (!isWorker) {
      caller = components.stack.caller.caller;
      func = caller.name;
      let file = caller.filename;
      if (file.includes(" -> ")) {
        file = caller.filename.split(/ -> /)[1];
      }
      path = file + ":" + caller.lineNumber;
    }

    let argOut = "(";
    if (args.length === 1) {
      argOut += aEvent;
    }

    let out = "EMITTING: ";

    // We need this try / catch to prevent any dead object errors.
    try {
      for (let i = 1; i < args.length; i++) {
        if (i === 1) {
          argOut = "(" + aEvent + ", ";
        } else {
          argOut += ", ";
        }

        let arg = args[i];
        argOut += arg;

        if (arg && arg.nodeName) {
          argOut += " (" + arg.nodeName;
          if (arg.id) {
            argOut += "#" + arg.id;
          }
          if (arg.className) {
            argOut += "." + arg.className;
          }
          argOut += ")";
        }
      }
    } catch(e) {
      // Object is dead so the toolbox is most likely shutting down,
      // do nothing.
    }

    argOut += ")";
    out += "emit" + argOut + " from " + func + "() -> " + path + "\n";

    dump(out);
  },
};

// });