react/packages/react-server-dom-webpack/src/ReactFlightServerWebpackBundlerConfig.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
 */

type WebpackMap = {
  [filepath: string]: {
    [name: string]: ModuleMetaData,
  },
};

export type BundlerConfig = WebpackMap;

// eslint-disable-next-line no-unused-vars
export type ModuleReference<T> = {
  $$typeof: symbol,
  filepath: string,
  name: string,
  async: boolean,
};

export type ModuleMetaData = {
  id: string,
  chunks: Array<string>,
  name: string,
  async: boolean,
};

export type ModuleKey = string;

const MODULE_TAG = Symbol.for('react.module.reference');

export function getModuleKey(reference: ModuleReference<any>): ModuleKey {
  return (
    reference.filepath +
    '#' +
    reference.name +
    (reference.async ? '#async' : '')
  );
}

export function isModuleReference(reference: Object): boolean {
  return reference.$$typeof === MODULE_TAG;
}

export function resolveModuleMetaData<T>(
  config: BundlerConfig,
  moduleReference: ModuleReference<T>,
): ModuleMetaData {
  const resolvedModuleData =
    config[moduleReference.filepath][moduleReference.name];
  if (moduleReference.async) {
    return {
      id: resolvedModuleData.id,
      chunks: resolvedModuleData.chunks,
      name: resolvedModuleData.name,
      async: true,
    };
  } else {
    return resolvedModuleData;
  }
}