Straight from the docs:

--check-formatted - check that the file is already formatted. This is useful in pre-commit hooks and CI scripts if you want to reject contributions with unformatted code. However, keep in mind, that the formatting output may differ between Elixir versions as improvements and fixes are applied to the formatter.

and

If any of the --check-* flags are given and a check fails, the formatted contents won’t be written to disk nor printed to stdout.

In the last bullet, I believe “Steam” should be “Stream.”

Working fine here too

Well done @doomspork - I am sure people are going to look forward to these updates