utils.js

const { inspect } = require('util');
const _ = require('lodash');

exports.createAssetsFilter = createAssetsFilter;

function createAssetsFilter(excludePatterns) {
  const excludeFunctions = _(excludePatterns)
    .castArray()
    .compact()
    .map(pattern => {
      if (typeof pattern === 'string') {
        pattern = new RegExp(pattern);
      }

      if (_.isRegExp(pattern)) {
        return (asset) => pattern.test(asset);
      }

      if (!_.isFunction(pattern)) {
        throw new TypeError(
          `Pattern should be either string, RegExp or a function, but "${inspect(pattern, { depth: 0 })}" got.`
        );
      }

      return pattern;
    })
    .value();

  if (excludeFunctions.length) {
    return (asset) => _.every(excludeFunctions, fn => fn(asset) !== true);
  } else {
    return () => true;
  }
}