function getAdditionalModulePaths(options = {}) {
  const baseUrl = options.baseUrl;

  if (!baseUrl) {
    return '';
  }

  const baseUrlResolved = path.resolve(paths.appPath, baseUrl);

  // We don't need to do anything if `baseUrl` is set to `node_modules`. This is
  // the default behavior.
  if (path.relative(paths.appNodeModules, baseUrlResolved) === '') {
    return null;
  }

  // Allow the user set the `baseUrl` to `appSrc`.
  if (path.relative(paths.appSrc, baseUrlResolved) === '') {
    return [paths.appSrc];
  }

  // If the path is equal to the root directory we ignore it here.
  // We don't want to allow importing from the root directly as source files are
  // not transpiled outside of `src`. We do allow importing them with the
  // absolute path (e.g. `src/Components/Button.js`) but we set that up with
  // an alias.
  if (path.relative(paths.appPath, baseUrlResolved) === '') {
    return null;
  }

  // Otherwise, throw an error.
  throw new Error(
    chalk.red.bold(
      "Your project's `baseUrl` can only be set to `src` or `node_modules`." +
        ' Create React App does not support other values at this time.'
    )
  );
}
Get additional module paths based on the baseUrl of a compilerOptions object.

@param {Object} options