Check scripts with shellcheck before accepting new commands

[pabs3]

No description provided.

[spacewander]

shellcheck is great. But to make the shellcheck happy with the existing scripts, we have to do a lot of things.

If we can not distinguish the new change and the existing code in a script, the contributor have to upgrade the existing code to pass the CI. This burden makes the contribution harder, especially when the contributor only wants to add a simple option or correct typo.

As the gatekeeper, I have already used shellcheck to verify each change, and ignored some warning manually. Sometimes SC2086: Double quote to prevent globbing and word splitting. is too strict.

[pabs3]

My intention was to only check new or changed scripts and I had a couple of solutions for that, but some missing features in xargs/grep on macOS and the age of bash on both the test platforms blocked me. I'll try to work on this more to find a solution that works in travis. shellcheck has a way to disable particular checks on particular lines: https://github.com/koalaman/shellcheck/wiki/Directive In general I've found that SC2086 (quoting) usually either is correct or is a sign that the script need to be changed to use bash arrays. Do you have an example of where it was too strict?

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-- bye, pabs https://bonedaddy.net/pabs3/

[pabs3]

I've come up with a new approach that checks all bash scripts changed or added in a commit. I had to drop testing the scripts on macOS because homebrew takes ages to install shellcheck and because of some incompatibilities. I figure it is fine to only check the scripts once as shellcheck probably behaves the same on both platforms anyway.

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-- bye, pabs https://bonedaddy.net/pabs3/