@splitsoftware/splitio-commons
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Split JavaScript SDK common components
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JavaScript
// @ts-nocheck
// Trimmed version of "events" library (https://www.npmjs.com/package/events).
// Removed features:
// - Max listener leak warning
// - EventEmitter.prototype.prependListener
// - EventEmitter.prototype.prependOnceListener
// - EventEmitter.prototype.listeners
// - EventEmitter.prototype.rawListeners
// - EventEmitter.prototype.listenerCount
// - EventEmitter.prototype.eventNames
//
// Copyright Joyent, Inc. and other Node contributors.
//
// 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.
var R = typeof Reflect === 'object' ? Reflect : null;
var ReflectApply = R && typeof R.apply === 'function'
? R.apply
: function ReflectApply(target, receiver, args) {
return Function.prototype.apply.call(target, receiver, args);
};
export var EventEmitter = function EventEmitter() {
EventEmitter.init.call(this);
};
EventEmitter.prototype._events = undefined;
EventEmitter.prototype._eventsCount = 0;
function checkListener(listener) {
if (typeof listener !== 'function') {
throw new TypeError('The "listener" argument must be of type Function. Received type ' + typeof listener);
}
}
EventEmitter.init = function () {
if (this._events === undefined ||
this._events === Object.getPrototypeOf(this)._events) {
this._events = Object.create(null);
this._eventsCount = 0;
}
};
EventEmitter.prototype.emit = function emit(type) {
var args = [];
for (var i = 1; i < arguments.length; i++)
args.push(arguments[i]);
var doError = (type === 'error');
var events = this._events;
if (events !== undefined)
doError = (doError && events.error === undefined);
else if (!doError)
return false;
// If there is no 'error' event listener then throw.
if (doError) {
var er;
if (args.length > 0)
er = args[0];
if (er instanceof Error) {
// Note: The comments on the `throw` lines are intentional, they show
// up in Node's output if this results in an unhandled exception.
throw er; // Unhandled 'error' event
}
// At least give some kind of context to the user
var err = new Error('Unhandled error.' + (er ? ' (' + er.message + ')' : ''));
err.context = er;
throw err; // Unhandled 'error' event
}
var handler = events[type];
if (handler === undefined)
return false;
if (typeof handler === 'function') {
ReflectApply(handler, this, args);
}
else {
var len = handler.length;
var listeners = arrayClone(handler, len);
for (var i_1 = 0; i_1 < len; ++i_1)
ReflectApply(listeners[i_1], this, args);
}
return true;
};
function _addListener(target, type, listener, prepend) {
var events;
var existing;
checkListener(listener);
events = target._events;
if (events === undefined) {
events = target._events = Object.create(null);
target._eventsCount = 0;
}
else {
// To avoid recursion in the case that type === "newListener"! Before
// adding it to the listeners, first emit "newListener".
if (events.newListener !== undefined) {
target.emit('newListener', type, listener.listener ? listener.listener : listener);
// Re-assign `events` because a newListener handler could have caused the
// this._events to be assigned to a new object
events = target._events;
}
existing = events[type];
}
if (existing === undefined) {
// Optimize the case of one listener. Don't need the extra array object.
existing = events[type] = listener;
++target._eventsCount;
}
else {
if (typeof existing === 'function') {
// Adding the second element, need to change to array.
existing = events[type] =
prepend ? [listener, existing] : [existing, listener];
// If we've already got an array, just append.
}
else if (prepend) {
existing.unshift(listener);
}
else {
existing.push(listener);
}
}
return target;
}
EventEmitter.prototype.addListener = function addListener(type, listener) {
return _addListener(this, type, listener, false);
};
EventEmitter.prototype.on = EventEmitter.prototype.addListener;
function onceWrapper() {
if (!this.fired) {
this.target.removeListener(this.type, this.wrapFn);
this.fired = true;
if (arguments.length === 0)
return this.listener.call(this.target);
return this.listener.apply(this.target, arguments);
}
}
function _onceWrap(target, type, listener) {
var state = { fired: false, wrapFn: undefined, target: target, type: type, listener: listener };
var wrapped = onceWrapper.bind(state);
wrapped.listener = listener;
state.wrapFn = wrapped;
return wrapped;
}
EventEmitter.prototype.once = function once(type, listener) {
checkListener(listener);
this.on(type, _onceWrap(this, type, listener));
return this;
};
// Emits a 'removeListener' event if and only if the listener was removed.
EventEmitter.prototype.removeListener =
function removeListener(type, listener) {
var list, events, position, i, originalListener;
checkListener(listener);
events = this._events;
if (events === undefined)
return this;
list = events[type];
if (list === undefined)
return this;
if (list === listener || list.listener === listener) {
if (--this._eventsCount === 0)
this._events = Object.create(null);
else {
delete events[type];
if (events.removeListener)
this.emit('removeListener', type, list.listener || listener);
}
}
else if (typeof list !== 'function') {
position = -1;
for (i = list.length - 1; i >= 0; i--) {
if (list[i] === listener || list[i].listener === listener) {
originalListener = list[i].listener;
position = i;
break;
}
}
if (position < 0)
return this;
if (position === 0)
list.shift();
else {
spliceOne(list, position);
}
if (list.length === 1)
events[type] = list[0];
if (events.removeListener !== undefined)
this.emit('removeListener', type, originalListener || listener);
}
return this;
};
EventEmitter.prototype.off = EventEmitter.prototype.removeListener;
EventEmitter.prototype.removeAllListeners =
function removeAllListeners(type) {
var listeners, events, i;
events = this._events;
if (events === undefined)
return this;
// not listening for removeListener, no need to emit
if (events.removeListener === undefined) {
if (arguments.length === 0) {
this._events = Object.create(null);
this._eventsCount = 0;
}
else if (events[type] !== undefined) {
if (--this._eventsCount === 0)
this._events = Object.create(null);
else
delete events[type];
}
return this;
}
// emit removeListener for all listeners on all events
if (arguments.length === 0) {
var keys = Object.keys(events);
var key;
for (i = 0; i < keys.length; ++i) {
key = keys[i];
if (key === 'removeListener')
continue;
this.removeAllListeners(key);
}
this.removeAllListeners('removeListener');
this._events = Object.create(null);
this._eventsCount = 0;
return this;
}
listeners = events[type];
if (typeof listeners === 'function') {
this.removeListener(type, listeners);
}
else if (listeners !== undefined) {
// LIFO order
for (i = listeners.length - 1; i >= 0; i--) {
this.removeListener(type, listeners[i]);
}
}
return this;
};
function arrayClone(arr, n) {
var copy = new Array(n);
for (var i = 0; i < n; ++i)
copy[i] = arr[i];
return copy;
}
function spliceOne(list, index) {
for (; index + 1 < list.length; index++)
list[index] = list[index + 1];
list.pop();
}