Exercise 4: My First Async I/O - fails with correct result

[thathurtabit]

Hi.

On exercise 4, when running verify, I get:

## MY FIRST ASYNC I/O! (Exercise 4 of 13)
Your submission results compared to the expected:

                 ACTUAL                                 EXPECTED
────────────────────────────────────────────────────────────────────────────────

   "27"                                ==    "27"
   ""                                  ==    ""

────────────────────────────────────────────────────────────────────────────────

 ✓

 Submission results match expected

 # FAIL Your solution to MY FIRST ASYNC I/O! didn't pass. Try again!

My solution was:

const fs = require("fs");
const promisify = require("util").promisify;

promisify(fs.readFile)(process.argv[2])
  .then(data => console.log(data.toString().split("\n").length - 1))
  .catch(error => console.log(error));

I'm not sure if this is my mistake as it says: Submission results match expected