Function compileJs

build-system/tasks/helpers.js:532–562

* Bundles (max) or compiles (min) a given JavaScript file entry point. * * @param {string} srcDir Path to the src directory * @param {string} srcFilename Name of the JS source file * @param {string} destDir Destination folder for output script * @param {?Object} options * @return {!Promise}

(srcDir, srcFilename, destDir, options)

 * @return {!Promise}
 */
async function compileJs(srcDir, srcFilename, destDir, options) {
  options = options || {};
  const entryPoint = path.join(srcDir, srcFilename);
  if (watchedEntryPoints.has(entryPoint)) {
    return;
  }

  if (options.watch) {
    watchedEntryPoints.add(entryPoint);
    const deps = await getDependencies(entryPoint, options);
    const watchFunc = async () => {
      await doCompileJs({...options, continueOnError: true});
    };
    watch(deps).on('change', debounce(watchFunc, watchDebounceDelay));
  }

  /**
   * Actually performs the steps to compile the entry point.
   * @param {object} options
   * @return {Promise<void>}
   */
  async function doCompileJs(options) {
    const buildResult = esbuildCompile(srcDir, srcFilename, destDir, options);
    if (options.onWatchBuild) {
      options.onWatchBuild(buildResult);
    }
    await buildResult;
  }

  await doCompileJs(options);
}

/**
 * Stops the timer for the given build step and prints the execution time.