[TacticalCoder]

Mandatory comment every time the subject comes up: shellcheck is really helpful when writing Bash scripts.

shellcheck itself is not written in Bash (it's written in Haskell) but it gives really good hints and find lots of bugs. If you disagree with some of its warnings, you can choose which ones you want to turn off.

I use it from within Emacs and it works fine. Set that thing once, years ago, and it's been helping me ever since.

Also: shellcheck probably ships with your Linux distro.