Type-ish – A runtime type checker for bash, in bash (opens in new tab)

Ah, wow. I like that they ported the accidental behavior deliberately into Windows:

Warning: The uninstallation process deletes the folder Steam was installed to to ensure it is fully uninstalled. If you accidentally installed Steam to a folder containing other data, for example C:\Program Files (x86)\ instead of C:\Program Files (x86)\Steam\..."

General recommendation specifically for the Valve-like case:

    set -o nounset

You can check variables as many ways you want, just do this too - safety net in case there's an eventual gap

shellharden is also great, that semi-automate the process to conform with shellcheck

I'm probably being too judgemental, but I don't get how people are so nonchalant about mutability and potentially destructive commands. Even in a Github Gist I'm scared enough to set -euo pipefail, put half a dozen checks before removing a folder...

Oh I do love reading those... Shame that shell scripting is still treated as mysterious command line voodoo, even Microsoft has Powershell now showing how powerful the concept is that even they couldn't avoid it entirely

You should also probably add either nullglob or failglob depending on your use case.

I would also add dotglob because it’s rarer for me to want only non-hidden files than it is for me to want all files.

And use the so-called "Bash unofficial strict mode", as described elsewhere.

I prefer this summary of it, because the original includes stuff like changing IFS (the fields separators) which I agree with the Gist author to not include, because it is a Bad Idea to blindly suggest it universally.

EDIT: This gist:

https://gist.github.com/robin-a-meade/58d60124b88b60816e8349...

If you ever check your arguments for any properties then this could still help, you'll have a systematic approach instead of an ad hoc one.

Booleans in shell scripts are little more than zero (true) and non-zero (false) exit codes.

Well, they are fairly transparent.

The problem is, they have a tendency to suddenly get horribly intransparent when they grow larger than maybe a few dozen lines.