async function _getRamOptions(
  entryFile: string,
  options: {
    dev: boolean,
    platform: ?string,
    ...
  },
  getDependencies: string => Iterable<string>,
  getTransformOptions: ?GetTransformOptions,
): Promise<
  $ReadOnly<{
    preloadedModules: $ReadOnly<{[string]: true, ...}>,
    ramGroups: $ReadOnlyArray<string>,
  }>,
> {
  if (getTransformOptions == null) {
    return {
      preloadedModules: {},
      ramGroups: [],
    };
  }

  const {preloadedModules, ramGroups} = await getTransformOptions(
    [entryFile],
    {dev: options.dev, hot: true, platform: options.platform},
    /* $FlowFixMe(>=0.99.0 site=react_native_fb) This comment suppresses an
     * error found when Flow v0.99 was deployed. To see the error, delete this
     * comment and run Flow. */
    async (x: string) => Array.from(getDependencies),
  );

  return {
    preloadedModules: preloadedModules || {},
    ramGroups: ramGroups || [],
  };
}
Returns the options needed to create a RAM bundle.