ReactFiberTreeReflection.js — react Source File

Source Code

/**
 * 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 type {
  Container,
  ActivityInstance,
  SuspenseInstance,
} from './ReactFiberConfig';
import type {ActivityState} from './ReactFiberActivityComponent';
import type {SuspenseState} from './ReactFiberSuspenseComponent';

import {
  HostComponent,
  HostHoistable,
  HostSingleton,
  HostRoot,
  HostPortal,
  HostText,
  ActivityComponent,
  SuspenseComponent,
  OffscreenComponent,
  Fragment,
} from './ReactWorkTags';
import {NoFlags, Placement, Hydrating} from './ReactFiberFlags';
import {enableFragmentRefsTextNodes} from 'shared/ReactFeatureFlags';

export function getNearestMountedFiber(fiber: Fiber): null | Fiber {
  let node = fiber;
  let nearestMounted: null | Fiber = fiber;
  // If there is no alternate, this might be a new tree that isn't inserted
  // yet. If it is, then it will have a pending insertion effect on it.
  let nextNode: Fiber = node;
  while (nextNode && !nextNode.alternate) {
    node = nextNode;
    if ((node.flags & (Placement | Hydrating)) !== NoFlags) {
      // This is an insertion or in-progress hydration. The nearest possible
      // mounted fiber is the parent but we need to continue to figure out
      // if that one is still mounted.
      nearestMounted = node.return;
    }
    // $FlowFixMe[incompatible-type] we bail out when we get a null
    nextNode = node.return;
  }
  // After we've reached an alternate, go the rest of the way to see if the
  // tree is still mounted. If it's not, its return pointer will be disconnected.
  while (node.return) {
    node = node.return;
  }
  if (node.tag === HostRoot) {
    // TODO: Check if this was a nested HostRoot when used with
    // renderContainerIntoSubtree.
    return nearestMounted;
  }
// ... (630 more lines)