ReactFizzNewContext.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 {ReactContext} from 'shared/ReactTypes';

import {isPrimaryRenderer} from './ReactFizzConfig';

let rendererSigil;
if (__DEV__) {
  // Use this to detect multiple renderers using the same context
  rendererSigil = {};
}

// Used to store the parent path of all context overrides in a shared linked list.
// Forming a reverse tree.
type ContextNode<T> = {
  parent: null | ContextNode<any>,
  depth: number, // Short hand to compute the depth of the tree at this node.
  context: ReactContext<T>,
  parentValue: T,
  value: T,
};

// The structure of a context snapshot is an implementation of this file.
// Currently, it's implemented as tracking the current active node.
export opaque type ContextSnapshot = null | ContextNode<any>;

export const rootContextSnapshot: ContextSnapshot = null;

// We assume that this runtime owns the "current" field on all ReactContext instances.
// This global (actually thread local) state represents what state all those "current",
// fields are currently in.
let currentActiveSnapshot: ContextSnapshot = null;

function popNode(prev: ContextNode<any>): void {
  if (isPrimaryRenderer) {
    prev.context._currentValue = prev.parentValue;
  } else {
    prev.context._currentValue2 = prev.parentValue;
  }
}

function pushNode(next: ContextNode<any>): void {
  if (isPrimaryRenderer) {
    next.context._currentValue = next.value;
  } else {
    next.context._currentValue2 = next.value;
  }
}

function popToNearestCommonAncestor(
  prev: ContextNode<any>,
  next: ContextNode<any>,
): void {
// ... (232 more lines)