Formatting and checking bash scripts

Everyone’s head of shellcheck for checking over scripts to ensure obvious (and not-so-obvious) mistakes aren’t being made. Afterwards I usually quite like to beautify/prettify/format up code to get all the usual readability improvements gained from this. In the past, I’ve used beautysh and while it’s worked, I generally don’t like using python programs when alternatives are available, and especially don’t like manually installing programs when it can be done via the package manager. In steps shfmt, a handy go program (no dependencies, portable, etc) that works exactly how you’d expect it to be run.

It can either be installed via your package manager, or you can install it from source using go:

go install mvdan.cc/sh/v3/cmd/shfmt@latest

Once installed, test it’s runnable

shfmt --version

With that confirmed, you can run it against a bash script as such:

shfmt -l -d path/to/your/script.sh

In the above example, the -l flag formats the text and the -d flag shows a diff of what’s been changed. If you’re happy with the changes shown, you can replace the -d flag with -w to overwrite the original file:

shfmt -l -w path/to/your/script.sh