getWatchedFiles = watcher => {
  const watchedDirs = watcher.getWatched();
  return Object.keys(watchedDirs).reduce(
    (acc, dir) => [
      ...acc,
      ...watchedDirs[dir].map(file => path.join(dir, file))
    ],
    []
  );
}
Return the list of absolute paths watched by a chokidar watcher.

@param watcher - Instance of a chokidar watcher
@return {string[]} - List of absolute paths
@ignore
@private