This commit is contained in:
Yamozha
2021-04-02 02:24:13 +03:00
parent c23950b545
commit 7256d79e2c
31493 changed files with 3036630 additions and 0 deletions

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/**
* Copyright (c) Facebook, Inc. and its affiliates.
*
* This source code is licensed under the MIT license found in the
* LICENSE file in the root directory of this source tree.
*
* @format
* @flow strict
*/
import type {ErrorUtilsT} from '../../polyfills/error-guard';
/**
* The particular require runtime that we are using looks for a global
* `ErrorUtils` object and if it exists, then it requires modules with the
* error handler specified via ErrorUtils.setGlobalHandler by calling the
* require function with applyWithGuard. Since the require module is loaded
* before any of the modules, this ErrorUtils must be defined (and the handler
* set) globally before requiring anything.
*
* However, we still want to treat ErrorUtils as a module so that other modules
* that use it aren't just using a global variable, so simply export the global
* variable here. ErrorUtils is originally defined in a file named error-guard.js.
*/
module.exports = (global.ErrorUtils: ErrorUtilsT);

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/**
* Copyright (c) Facebook, Inc. and its affiliates.
*
* This source code is licensed under the MIT license found in the
* LICENSE file in the root directory of this source tree.
*
* @format
* @flow
*/
'use strict';
const EventSubscription = require('./EventSubscription');
import type EventEmitter from './EventEmitter';
import type EventSubscriptionVendor from './EventSubscriptionVendor';
/**
* EmitterSubscription represents a subscription with listener and context data.
*/
class EmitterSubscription extends EventSubscription {
emitter: EventEmitter;
listener: Function;
context: ?Object;
/**
* @param {EventEmitter} emitter - The event emitter that registered this
* subscription
* @param {EventSubscriptionVendor} subscriber - The subscriber that controls
* this subscription
* @param {function} listener - Function to invoke when the specified event is
* emitted
* @param {*} context - Optional context object to use when invoking the
* listener
*/
constructor(
emitter: EventEmitter,
subscriber: EventSubscriptionVendor,
listener: Function,
context: ?Object,
) {
super(subscriber);
this.emitter = emitter;
this.listener = listener;
this.context = context;
}
/**
* Removes this subscription from the emitter that registered it.
* Note: we're overriding the `remove()` method of EventSubscription here
* but deliberately not calling `super.remove()` as the responsibility
* for removing the subscription lies with the EventEmitter.
*/
remove() {
this.emitter.removeSubscription(this);
}
}
module.exports = EmitterSubscription;

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/**
* Copyright (c) Facebook, Inc. and its affiliates.
*
* This source code is licensed under the MIT license found in the
* LICENSE file in the root directory of this source tree.
*
* @format
* @noflow
* @typecheck
*/
'use strict';
const EmitterSubscription = require('./EmitterSubscription');
const EventSubscriptionVendor = require('./EventSubscriptionVendor');
const invariant = require('invariant');
const sparseFilterPredicate = () => true;
/**
* @class EventEmitter
* @description
* An EventEmitter is responsible for managing a set of listeners and publishing
* events to them when it is told that such events happened. In addition to the
* data for the given event it also sends a event control object which allows
* the listeners/handlers to prevent the default behavior of the given event.
*
* The emitter is designed to be generic enough to support all the different
* contexts in which one might want to emit events. It is a simple multicast
* mechanism on top of which extra functionality can be composed. For example, a
* more advanced emitter may use an EventHolder and EventFactory.
*/
class EventEmitter {
_subscriber: EventSubscriptionVendor;
_currentSubscription: ?EmitterSubscription;
/**
* @constructor
*
* @param {EventSubscriptionVendor} subscriber - Optional subscriber instance
* to use. If omitted, a new subscriber will be created for the emitter.
*/
constructor(subscriber: ?EventSubscriptionVendor) {
this._subscriber = subscriber || new EventSubscriptionVendor();
}
/**
* Adds a listener to be invoked when events of the specified type are
* emitted. An optional calling context may be provided. The data arguments
* emitted will be passed to the listener function.
*
* TODO: Annotate the listener arg's type. This is tricky because listeners
* can be invoked with varargs.
*
* @param {string} eventType - Name of the event to listen to
* @param {function} listener - Function to invoke when the specified event is
* emitted
* @param {*} context - Optional context object to use when invoking the
* listener
*/
addListener(
eventType: string,
listener: Function,
context: ?Object,
): EmitterSubscription {
return (this._subscriber.addSubscription(
eventType,
new EmitterSubscription(this, this._subscriber, listener, context),
): any);
}
/**
* Similar to addListener, except that the listener is removed after it is
* invoked once.
*
* @param {string} eventType - Name of the event to listen to
* @param {function} listener - Function to invoke only once when the
* specified event is emitted
* @param {*} context - Optional context object to use when invoking the
* listener
*/
once(
eventType: string,
listener: Function,
context: ?Object,
): EmitterSubscription {
return this.addListener(eventType, (...args) => {
this.removeCurrentListener();
listener.apply(context, args);
});
}
/**
* Removes all of the registered listeners, including those registered as
* listener maps.
*
* @param {?string} eventType - Optional name of the event whose registered
* listeners to remove
*/
removeAllListeners(eventType: ?string) {
this._subscriber.removeAllSubscriptions(eventType);
}
/**
* Provides an API that can be called during an eventing cycle to remove the
* last listener that was invoked. This allows a developer to provide an event
* object that can remove the listener (or listener map) during the
* invocation.
*
* If it is called when not inside of an emitting cycle it will throw.
*
* @throws {Error} When called not during an eventing cycle
*
* @example
* var subscription = emitter.addListenerMap({
* someEvent: function(data, event) {
* console.log(data);
* emitter.removeCurrentListener();
* }
* });
*
* emitter.emit('someEvent', 'abc'); // logs 'abc'
* emitter.emit('someEvent', 'def'); // does not log anything
*/
removeCurrentListener() {
invariant(
!!this._currentSubscription,
'Not in an emitting cycle; there is no current subscription',
);
this.removeSubscription(this._currentSubscription);
}
/**
* Removes a specific subscription. Called by the `remove()` method of the
* subscription itself to ensure any necessary cleanup is performed.
*/
removeSubscription(subscription: EmitterSubscription) {
invariant(
subscription.emitter === this,
'Subscription does not belong to this emitter.',
);
this._subscriber.removeSubscription(subscription);
}
/**
* Returns an array of listeners that are currently registered for the given
* event.
*
* @param {string} eventType - Name of the event to query
* @returns {array}
*/
listeners(eventType: string): [EmitterSubscription] {
const subscriptions = this._subscriber.getSubscriptionsForType(eventType);
return subscriptions
? subscriptions
// We filter out missing entries because the array is sparse.
// "callbackfn is called only for elements of the array which actually
// exist; it is not called for missing elements of the array."
// https://www.ecma-international.org/ecma-262/9.0/index.html#sec-array.prototype.filter
.filter(sparseFilterPredicate)
.map(subscription => subscription.listener)
: [];
}
/**
* Emits an event of the given type with the given data. All handlers of that
* particular type will be notified.
*
* @param {string} eventType - Name of the event to emit
* @param {...*} Arbitrary arguments to be passed to each registered listener
*
* @example
* emitter.addListener('someEvent', function(message) {
* console.log(message);
* });
*
* emitter.emit('someEvent', 'abc'); // logs 'abc'
*/
emit(eventType: string) {
const subscriptions = this._subscriber.getSubscriptionsForType(eventType);
if (subscriptions) {
for (let i = 0, l = subscriptions.length; i < l; i++) {
const subscription = subscriptions[i];
// The subscription may have been removed during this event loop.
if (subscription && subscription.listener) {
this._currentSubscription = subscription;
subscription.listener.apply(
subscription.context,
Array.prototype.slice.call(arguments, 1),
);
}
}
this._currentSubscription = null;
}
}
/**
* Removes the given listener for event of specific type.
*
* @param {string} eventType - Name of the event to emit
* @param {function} listener - Function to invoke when the specified event is
* emitted
*
* @example
* emitter.removeListener('someEvent', function(message) {
* console.log(message);
* }); // removes the listener if already registered
*
*/
removeListener(eventType: String, listener) {
const subscriptions = this._subscriber.getSubscriptionsForType(eventType);
if (subscriptions) {
for (let i = 0, l = subscriptions.length; i < l; i++) {
const subscription = subscriptions[i];
// The subscription may have been removed during this event loop.
// its listener matches the listener in method parameters
if (subscription && subscription.listener === listener) {
subscription.remove();
}
}
}
}
}
module.exports = EventEmitter;

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/**
* Copyright (c) Facebook, Inc. and its affiliates.
*
* This source code is licensed under the MIT license found in the
* LICENSE file in the root directory of this source tree.
*
* @format
* @flow strict-local
*/
'use strict';
import type EventSubscriptionVendor from './EventSubscriptionVendor';
/**
* EventSubscription represents a subscription to a particular event. It can
* remove its own subscription.
*/
class EventSubscription {
eventType: string;
key: number;
subscriber: EventSubscriptionVendor;
/**
* @param {EventSubscriptionVendor} subscriber the subscriber that controls
* this subscription.
*/
constructor(subscriber: EventSubscriptionVendor) {
this.subscriber = subscriber;
}
/**
* Removes this subscription from the subscriber that controls it.
*/
remove() {
this.subscriber.removeSubscription(this);
}
}
module.exports = EventSubscription;

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/**
* Copyright (c) Facebook, Inc. and its affiliates.
*
* This source code is licensed under the MIT license found in the
* LICENSE file in the root directory of this source tree.
*
* @format
* @flow
*/
'use strict';
const invariant = require('invariant');
import type EventSubscription from './EventSubscription';
/**
* EventSubscriptionVendor stores a set of EventSubscriptions that are
* subscribed to a particular event type.
*/
class EventSubscriptionVendor {
_subscriptionsForType: Object;
_currentSubscription: ?EventSubscription;
constructor() {
this._subscriptionsForType = {};
this._currentSubscription = null;
}
/**
* Adds a subscription keyed by an event type.
*
* @param {string} eventType
* @param {EventSubscription} subscription
*/
addSubscription(
eventType: string,
subscription: EventSubscription,
): EventSubscription {
invariant(
subscription.subscriber === this,
'The subscriber of the subscription is incorrectly set.',
);
if (!this._subscriptionsForType[eventType]) {
this._subscriptionsForType[eventType] = [];
}
const key = this._subscriptionsForType[eventType].length;
this._subscriptionsForType[eventType].push(subscription);
subscription.eventType = eventType;
subscription.key = key;
return subscription;
}
/**
* Removes a bulk set of the subscriptions.
*
* @param {?string} eventType - Optional name of the event type whose
* registered supscriptions to remove, if null remove all subscriptions.
*/
removeAllSubscriptions(eventType: ?string) {
if (eventType === undefined) {
this._subscriptionsForType = {};
} else {
delete this._subscriptionsForType[eventType];
}
}
/**
* Removes a specific subscription. Instead of calling this function, call
* `subscription.remove()` directly.
*
* @param {object} subscription
*/
removeSubscription(subscription: Object) {
const eventType = subscription.eventType;
const key = subscription.key;
const subscriptionsForType = this._subscriptionsForType[eventType];
if (subscriptionsForType) {
delete subscriptionsForType[key];
}
}
/**
* Returns the array of subscriptions that are currently registered for the
* given event type.
*
* Note: This array can be potentially sparse as subscriptions are deleted
* from it when they are removed.
*
* TODO: This returns a nullable array. wat?
*
* @param {string} eventType
* @returns {?array}
*/
getSubscriptionsForType(eventType: string): ?[EventSubscription] {
return this._subscriptionsForType[eventType];
}
}
module.exports = EventSubscriptionVendor;