move event manager to separate class

lib/backburner/evented.ts

@@ -0,0 +1,65 @@
+
+export default class Evented {
+
+ private _eventCallbacks: {
+ end: Function[];
+ begin: Function[];
+ } = {
+ end: [],
+ begin: []
+ };
+
+ public on(eventName, callback) {
+ if (typeof callback !== 'function') {
+ throw new TypeError(`Callback must be a function`);
+ }
+ let callbacks = this._eventCallbacks[eventName];
+ if (callbacks !== undefined) {
+ callbacks.push(callback);
+ } else {
+ throw new TypeError(`Cannot on() event ${eventName} because it does not exist`);
+ }
+ }
+
+ public off(eventName, callback) {
+ let callbacks = this._eventCallbacks[eventName];
+ if (!eventName || callbacks === undefined) {
+ throw new TypeError(`Cannot off() event ${eventName} because it does not exist`);
+ }
+ let callbackFound = false;
+ if (callback) {
+ for (let i = 0; i < callbacks.length; i++) {
+ if (callbacks[i] === callback) {
+ callbackFound = true;
+ callbacks.splice(i, 1);
+ i--;
+ }
+ }
+ }
+ if (!callbackFound) {
+ throw new TypeError(`Cannot off() callback that does not exist`);
+ }
+ }
+
+ /**
+ Trigger an event. Supports up to two arguments. Designed around
+ triggering transition events from one run loop instance to the
+ next, which requires an argument for the first instance and then
+ an argument for the next instance.
+
+ @protected
+ @method _trigger
+ @param {String} eventName
+ @param {any} arg1
+ @param {any} arg2
+ */
+ protected _trigger<T, U>(eventName: string, arg1: T, arg2: U) {
+ let callbacks = this._eventCallbacks[eventName];
+ if (callbacks !== undefined) {
+ for (let i = 0; i < callbacks.length; i++) {
+ callbacks[i](arg1, arg2);
+ }
+ }
+ }
+
+}

lib/index.ts

@@ -1,16 +1,15 @@
+import searchTimer from './backburner/binary-search';
+import DeferredActionQueues from './backburner/deferred-action-queues';
+import Evented from './backburner/evented';
+import iteratorDrain, { Iteratable } from './backburner/iterator-drain';
+import Queue, { QUEUE_STATE } from './backburner/queue';
 import {
  findItem,
  findTimer,
  getOnError,
  isCoercableNumber
 } from './backburner/utils';
 
-import searchTimer from './backburner/binary-search';
-import DeferredActionQueues from './backburner/deferred-action-queues';
-import iteratorDrain, { Iteratable } from './backburner/iterator-drain';
-
-import Queue, { QUEUE_STATE } from './backburner/queue';
-
 type Timer = any;
 
 const noop = function() {};
@@ -45,7 +44,7 @@ function parseArgs() {
 
 let UUID = 0;
 
-export default class Backburner {
+export default class Backburner extends Evented {
  public static Queue = Queue;
 
  public DEBUG = false;
@@ -60,13 +59,6 @@ export default class Backburner {
  private instanceStack: DeferredActionQueues[] = [];
  private _debouncees: any[] = [];
  private _throttlers: any[] = [];
- private _eventCallbacks: {
- end: Function[];
- begin: Function[];
- } = {
- end: [],
- begin: []
- };
 
  private _timerTimeoutId: number | null = null;
  private _timers: any[] = [];
@@ -83,7 +75,8 @@ export default class Backburner {
  private _autorun: number | null = null;
  private _boundAutorunEnd: () => void;
 
- constructor(queueNames: string[], options: any = {} ) {
+ constructor(queueNames: string[], options: any = {}) {
+ super();
  this.queueNames = queueNames;
  this.options = options;
  if (!this.options.defaultQueue) {
@@ -172,38 +165,6 @@ export default class Backburner {
  }
  }
 
- public on(eventName, callback) {
- if (typeof callback !== 'function') {
- throw new TypeError(`Callback must be a function`);
- }
- let callbacks = this._eventCallbacks[eventName];
- if (callbacks !== undefined) {
- callbacks.push(callback);
- } else {
- throw new TypeError(`Cannot on() event ${eventName} because it does not exist`);
- }
- }
-
- public off(eventName, callback) {
- let callbacks = this._eventCallbacks[eventName];
- if (!eventName || callbacks === undefined) {
- throw new TypeError(`Cannot off() event ${eventName} because it does not exist`);
- }
- let callbackFound = false;
- if (callback) {
- for (let i = 0; i < callbacks.length; i++) {
- if (callbacks[i] === callback) {
- callbackFound = true;
- callbacks.splice(i, 1);
- i--;
- }
- }
- }
- if (!callbackFound) {
- throw new TypeError(`Cannot off() callback that does not exist`);
- }
- }
-
  public run(target: Function);
  public run(target: Function | any | null, method?: Function | string, ...args);
  public run(target: any | null | undefined, method?: Function, ...args: any[]);
@@ -614,27 +575,6 @@ export default class Backburner {
  return false;
  }
 
- /**
- Trigger an event. Supports up to two arguments. Designed around
- triggering transition events from one run loop instance to the
- next, which requires an argument for the first instance and then
- an argument for the next instance.
-
- @private
- @method _trigger
- @param {String} eventName
- @param {any} arg1
- @param {any} arg2
- */
- private _trigger<T, U>(eventName: string, arg1: T, arg2: U) {
- let callbacks = this._eventCallbacks[eventName];
- if (callbacks !== undefined) {
- for (let i = 0; i < callbacks.length; i++) {
- callbacks[i](arg1, arg2);
- }
- }
- }
-
  private _runExpiredTimers() {
  this._timerTimeoutId = null;
  if (this._timers.length > 0) {