old_contents: var fs = require('fs');
  
  function lines(err, data) {
    return console.log(data.split('\n').length - 1);
  }
  
  fs.readFile(process.argv[2], 'utf8', lines)
  
new_contents: var fs = require('fs');
  
  function lines (err, data) {
    return console.log(data.split('\n').length - 1);
  }
  
  fs.readFile(process.argv[2], 'utf8', lines)
  
subject: Add missing space