How to use the babel-core.util.regexify function in babel-core

function shouldIgnoreBabelrc(filename, babelrc) {
  // Determine if we should ignore this babelrc file. We do this here instead of
  // letting babel-core handle it because this config might be merged with our
  // autogenerated one later which shouldn't be ignored.
  let ignore = babelUtils.arrayify(babelrc.ignore, babelUtils.regexify);
  let only =
    babelrc.only && babelUtils.arrayify(babelrc.only, babelUtils.regexify);
  return babelUtils.shouldIgnore(filename, ignore, only);
}

if (errors.length) {
  console.error(errors.join(". "));
  process.exit(2);
}

//

var opts = exports.opts = {};

each(options, function (opt, key) {
  if (commander[key] !== undefined) {
    opts[key] = commander[key];
  }
});

opts.ignore = util.arrayify(opts.ignore, util.regexify);

if (opts.only) {
  opts.only = util.arrayify(opts.only, util.regexify);
}

var fn = /*istanbul ignore next*/void 0;

if (commander.outDir) {
  fn = require("./dir");
} else {
  fn = require("./file");
}

fn(commander, filenames, exports.opts);

if (errors.length) {
  console.error(errors.join(". "));
  process.exit(2);
}

//

var opts = exports.opts = {};

each(options, function (opt, key) {
  if (commander[key] !== undefined) {
    opts[key] = commander[key];
  }
});

opts.ignore = util.arrayify(opts.ignore, util.regexify);

if (opts.only) {
  opts.only = util.arrayify(opts.only, util.regexify);
}

var fn;

if (commander.outDir) {
  fn = require("./dir");
} else {
  fn = require("./file");
}

fn(commander, filenames, exports.opts);

if (errors.length) {
  console.error(errors.join(". "));
  process.exit(2);
}

var opts = exports.opts = {};

(0, _keys2.default)(options).forEach(function (key) {
  var opt = options[key];
  if (commander[key] !== undefined && commander[key] !== opt.default) {
    opts[key] = commander[key];
  }
});

opts.ignore = util.arrayify(opts.ignore, util.regexify);

if (opts.only) {
  opts.only = util.arrayify(opts.only, util.regexify);
}

var fn = void 0;

if (commander.outDir) {
  fn = require("./dir");
} else {
  fn = require("./file");
}

fn(commander, filenames, exports.opts);

if (errors.length) {
  console.error(errors.join(". "));
  process.exit(2);
}

//

var opts = exports.opts = {};

each(options, function (opt, key) {
  if (commander[key] !== undefined) {
    opts[key] = commander[key];
  }
});

opts.ignore = util.arrayify(opts.ignore, util.regexify);

if (opts.only) {
  opts.only = util.arrayify(opts.only, util.regexify);
}

var fn = /*istanbul ignore next*/void 0;

if (commander.outDir) {
  fn = require("./dir");
} else {
  fn = require("./file");
}

fn(commander, filenames, exports.opts);

function shouldIgnoreByBabel(filename, babelrc) {
    if (!babelrc.ignore && !babelrc.only) {
        return /node_modules/.test(filename);
    } else {
        var ignore = babelrc.ignore ? util.arrayify(babelrc.ignore, util.regexify) : null;
        var only = babelrc.only ? util.arrayify(babelrc.only, util.regexify) : null;
        return util.shouldIgnore(filename, ignore, only);
    }
}

function skip ({ opts, file } = { }) {
  if (file && opts) {
    const { ignore = [], only } = opts
    return util.shouldIgnore(
      file.opts.filename,
      util.arrayify(ignore, util.regexify),
      only ? util.arrayify(only, util.regexify) : null
    )
  }
  return false
}

function skip ({ opts, file } = { }) {
  if (file && opts) {
    const { ignore = [], only } = opts
    return util.shouldIgnore(
      file.opts.filename,
      util.arrayify(ignore, util.regexify),
      only ? util.arrayify(only, util.regexify) : null
    )
  }
  return false
}

export default function (opts?: Object = {}) {
  if (opts.only != null) only = util.arrayify(opts.only, util.regexify);
  if (opts.ignore != null) ignore = util.arrayify(opts.ignore, util.regexify);

  if (opts.extensions) hookExtensions(util.arrayify(opts.extensions));

  if (opts.cache === false) cache = null;

  delete opts.extensions;
  delete opts.ignore;
  delete opts.cache;
  delete opts.only;

  extend(transformOpts, opts);
}

}

//

var opts = exports.opts = {};

each(options, function (opt, key) {
  if (commander[key] !== undefined) {
    opts[key] = commander[key];
  }
});

opts.ignore = util.arrayify(opts.ignore, util.regexify);

if (opts.only) {
  opts.only = util.arrayify(opts.only, util.regexify);
}

var fn;

if (commander.outDir) {
  fn = require("./dir");
} else {
  fn = require("./file");
}

fn(commander, filenames, exports.opts);