| 1 | /** |
| 2 | * Copyright (c) Meta Platforms, Inc. and affiliates. |
| 3 | * |
| 4 | * This source code is licensed under the MIT license found in the |
| 5 | * LICENSE file in the root directory of this source tree. |
| 6 | * |
| 7 | * @flow |
| 8 | */ |
| 9 | |
| 10 | import {disableLegacyMode} from 'shared/ReactFeatureFlags'; |
| 11 | import {DiscreteEventPriority} from 'react-reconciler/src/ReactEventPriorities'; |
| 12 | |
| 13 | import ReactSharedInternals from 'shared/ReactSharedInternals'; |
| 14 | |
| 15 | import ReactDOMSharedInternals from 'shared/ReactDOMSharedInternals'; |
| 16 | |
| 17 | declare function flushSyncImpl<R>(fn: () => R): R; |
| 18 | declare function flushSyncImpl(void): void; |
| 19 | function flushSyncImpl<R>(fn: (() => R) | void): R | void { |
| 20 | const previousTransition = ReactSharedInternals.T; |
| 21 | const previousUpdatePriority = |
| 22 | ReactDOMSharedInternals.p; /* ReactDOMCurrentUpdatePriority */ |
| 23 | |
| 24 | try { |
| 25 | ReactSharedInternals.T = null; |
| 26 | ReactDOMSharedInternals.p /* ReactDOMCurrentUpdatePriority */ = |
| 27 | DiscreteEventPriority; |
| 28 | if (fn) { |
| 29 | return fn(); |
| 30 | } else { |
| 31 | return undefined; |
| 32 | } |
| 33 | } finally { |
| 34 | ReactSharedInternals.T = previousTransition; |
| 35 | ReactDOMSharedInternals.p /* ReactDOMCurrentUpdatePriority */ = |
| 36 | previousUpdatePriority; |
| 37 | const wasInRender = |
| 38 | ReactDOMSharedInternals.d /* ReactDOMCurrentDispatcher */ |
| 39 | .f(); /* flushSyncWork */ |
| 40 | if (__DEV__) { |
| 41 | if (wasInRender) { |
| 42 | console.error( |
| 43 | 'flushSync was called from inside a lifecycle method. React cannot ' + |
| 44 | 'flush when React is already rendering. Consider moving this call to ' + |
| 45 | 'a scheduler task or micro task.', |
| 46 | ); |
| 47 | } |
| 48 | } |
| 49 | } |
| 50 | } |
| 51 | |
| 52 | declare function flushSyncErrorInBuildsThatSupportLegacyMode<R>(fn: () => R): R; |
| 53 | declare function flushSyncErrorInBuildsThatSupportLegacyMode(void): void; |
| 54 | function flushSyncErrorInBuildsThatSupportLegacyMode() { |
| 55 | // eslint-disable-next-line react-internal/prod-error-codes |
| 56 | throw new Error( |
| 57 | 'Expected this build of React to not support legacy mode but it does. This is a bug in React.', |
| 58 | ); |
| 59 | } |
| 60 | |
| 61 | export const flushSync: typeof flushSyncImpl = disableLegacyMode |
| 62 | ? flushSyncImpl |
| 63 | : flushSyncErrorInBuildsThatSupportLegacyMode; |