text: 'use strict';
  
  const fs = require('fs');
  const util = require('util');
  
  // Wrap the fs.readFile method with our interface so that we can properly test it modularly.
  const readerWithCallback = (file, callback) => {
    fs.readFile(file, (err, data) => {
      if (err) { callback(err); }
      else { callback(undefined, data.toString().trim()); }
    });
  };
  
  // As a promise
  const readFilePromise = util.promisify(fs.readFile);
  const readerWithPromise = (file) => {
    return readFilePromise(file)
      .then(contents => contents.toString().trim())
      .catch(error => error);
  };
  
  module.exports = { readerWithCallback, readerWithPromise };