react/packages/react-reconciler/src/ReactCurrentFiber.js

/**
 * Copyright (c) Meta Platforms, Inc. and 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 {Fiber} from './ReactInternalTypes';

import ReactSharedInternals from 'shared/ReactSharedInternals';
import {getOwnerStackByFiberInDev} from './ReactFiberComponentStack';
import {getComponentNameFromOwner} from 'react-reconciler/src/getComponentNameFromFiber';

export let current: Fiber | null = null;
export let isRendering: boolean = false;

export function getCurrentFiberOwnerNameInDevOrNull(): string | null {
  if (__DEV__) {
    if (current === null) {
      return null;
    }
    const owner = current._debugOwner;
    if (owner != null) {
      return getComponentNameFromOwner(owner);
    }
  }
  return null;
}

function getCurrentFiberStackInDev(): string {
  if (__DEV__) {
    if (current === null) {
      return '';
    }
    // Safe because if current fiber exists, we are reconciling,
    // and it is guaranteed to be the work-in-progress version.
    // TODO: The above comment is not actually true. We might be
    // in a commit phase or preemptive set state callback.
    return getOwnerStackByFiberInDev(current);
  }
  return '';
}

export function runWithFiberInDEV<A0, A1, A2, A3, A4, T>(
  fiber: null | Fiber,
  callback: (A0, A1, A2, A3, A4) => T,
  arg0: A0,
  arg1: A1,
  arg2: A2,
  arg3: A3,
  arg4: A4,
): T {
  if (__DEV__) {
    const previousFiber = current;
    setCurrentFiber(fiber);
    try {
      if (fiber !== null && fiber._debugTask) {
        return fiber._debugTask.run(
          callback.bind(null, arg0, arg1, arg2, arg3, arg4),
        );
      }
      return callback(arg0, arg1, arg2, arg3, arg4);
    } finally {
      setCurrentFiber(previousFiber);
    }
  }
  // These errors should never make it into a build so we don't need to encode them in codes.json
  // eslint-disable-next-line react-internal/prod-error-codes
  throw new Error(
    'runWithFiberInDEV should never be called in production. This is a bug in React.',
  );
}

export function resetCurrentFiber() {
  if (__DEV__) {
    ReactSharedInternals.getCurrentStack = null;
    isRendering = false;
  }
  current = null;
}

export function setCurrentFiber(fiber: Fiber | null) {
  if (__DEV__) {
    ReactSharedInternals.getCurrentStack =
      fiber === null ? null : getCurrentFiberStackInDev;
    isRendering = false;
  }
  current = fiber;
}

export function setIsRendering(rendering: boolean) {
  if (__DEV__) {
    isRendering = rendering;
  }
}

export function getIsRendering(): void | boolean {
  if (__DEV__) {
    return isRendering;
  }
}