ci: add style check for doc comments

[Akmadan23]

Discussed in #2555 (comment)

[alex-courtis]

I always try to use /bin/sh after I caused a shell compatibility production incident 20 years ago.

However, we need bash features here and we know that CI provides bash so we are OK.

[gegoune]

If you insist on sh (it's fine either way):

#!/bin/sh

out=$(grep -nr "^--- @" lua)

if [ "$out" ]; then
	last_file=""
	printf %s "$out" | while read -r line; do
		file="$(echo "$line" | cut -d: -f1)"
		if [ "$file" != "$last_file" ]; then
			echo "$file:" >&2
			last_file="$file"
		fi
		echo "$line" | awk -F: '{ printf("  line %s: %s\n", $2, $3) }' >&2
	done
	exit 1
fi

[alex-courtis]

Works nicely, shellcheck is happy.

TIL print pipe into while

Edit: let's just go with bash; I'm being finicky

[alex-courtis]

Fails nicely.

shellcheck 👍

We're going to need to fix all these before we can merge: find lua -type f -exec sed -i 's/^--- @/---@/g' {} \;

[alex-courtis]

CI all passing now