hack/validate/pr-gh-references

#!/usr/bin/env bash

set -Ee -o pipefail

SCRIPTDIR="$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)"
source "${SCRIPTDIR}/.validate"

ghShorthandRegex='(^|[^[:alnum:]_])#[0-9]+'
ghRefPrefixRegex='(^|[^[:alnum:]_./-])'
ghRepoNameRegex='[[:alnum:]_.-]+'
ghRepoRefRegex="${ghRefPrefixRegex}${ghRepoNameRegex}#[0-9]+"
ghOwnerRepoRefRegex="${ghRefPrefixRegex}${ghRepoNameRegex}/${ghRepoNameRegex}#[0-9]+"
ghURLRegex='https?://(www\.)?github\.com/[^[:space:]/]+/[^[:space:]/]+/(issues|pull)/[0-9]+'
badReferences=()

check_references() {
	local source="$1"
	local content="$2"
	local matches

	matches=$(grep -En -e "$ghShorthandRegex" -e "$ghRepoRefRegex" -e "$ghOwnerRepoRefRegex" -e "$ghURLRegex" <<< "$content" || true)
	if [ -n "$matches" ]; then
		badReferences+=("$source")
		echo "::error::${source} contains a GitHub issue or PR reference. Reference commit hashes instead."
	fi
}

for commit in $(validate_log --format='format:%H%n'); do
	if [ -z "$(git log -1 --format='format:' --name-status "$commit")" ]; then
		# no content (ie, Merge commit, etc)
		continue
	fi
	check_references "Commit $commit" "$(git log -1 --format='format:%B' "$commit")"
done

if [ "${#badReferences[@]}" -ne 0 ]; then
	printf "\nPlease remove GitHub issue or PR references from commit messages.\n"
	printf "Reference commit hashes instead.\n"
	printf "Keep GitHub issue or PR references in GitHub-visible text, such as PR descriptions or comments.\n"
	exit 1
fi