/** * 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. * @flow */ import type {ReactEventResponder, ReactEventComponent} from 'shared/ReactTypes'; import {REACT_EVENT_COMPONENT_TYPE} from 'shared/ReactSymbols'; import {hasBadMapPolyfill} from './hasBadMapPolyfill'; export default function createEventComponent( responder: ReactEventResponder, ): ReactEventComponent { // We use responder as a Map key later on. When we have a bad // polyfill, then we can't use it as a key as the polyfill tries // to add a property to the object. if (__DEV__ && !hasBadMapPolyfill) { Object.freeze(responder); } const eventComponent = { $$typeof: REACT_EVENT_COMPONENT_TYPE, responder, }; if (__DEV__) { Object.freeze(eventComponent); } return eventComponent; }