Function splitWrapper

build-system/tasks/helpers.js:280–288

* Splits up the wrapper to compute the banner and footer * @return {object}

()

   * @return {object}
   */
  function splitWrapper() {
    const wrapper = options.wrapper ?? wrappers.none;
    const sentinel = '<%= contents %>';
    const start = wrapper.indexOf(sentinel);
    return {
      banner: {js: wrapper.slice(0, start)},
      footer: {js: wrapper.slice(start + sentinel.length)},
    };
  }
  const {banner, footer} = splitWrapper();
  const config = await getAmpConfigForFile(destFilename, options);
  const compiledFile = await getCompiledFile(srcFilename);