build: resolve co-authors from commits

Author: Planeshifter

.github/workflows/scripts/generate_pr_commit_message

@@ -56,6 +56,23 @@ on_error() {
 	exit "$1"
 }
 
+# Resolves a name and email using .mailmap via git check-mailmap, falling back to the provided values if no match is found.
+#
+# $1 - name
+# $2 - email
+resolve_name_email() {
+	local name="$1"
+	local email="$2"
+	local resolved
+
+	resolved=$(git check-mailmap "$name <$email>" 2>/dev/null)
+	if [ -n "$resolved" ]; then
+		echo "$resolved"
+	else
+		echo "$name <$email>"
+	fi
+}
+
 # Resolves GitHub handle to name and email using .mailmap.
 #
 # $1 - GitHub handle
@@ -76,24 +93,47 @@ resolve_user() {
 	fi
 }
 
-# Makes authenticated GitHub API requests.
+# Makes GitHub API requests.
 #
 # $1 - HTTP method (GET or POST)
 # $2 - API endpoint
-# $3 - Data for POST requests
+# $3 - data for POST requests
 github_api() {
 	local method="$1"
 	local endpoint="$2"
 	local data="$3"
 
-	if [ "$method" == "GET" ]; then
-		curl -s -H "Authorization: token $GITHUB_TOKEN" "$GITHUB_API_URL$endpoint"
-	elif [ "$method" == "POST" ]; then
-		curl -s -X POST -H "Authorization: token $GITHUB_TOKEN" -H "Content-Type: application/json" -d "$data" "$GITHUB_API_URL$endpoint"
-	else
-		echo "Invalid HTTP method: $method"
-		on_error 1
+	# Initialize an array to hold curl headers:
+	local headers=()
+
+	# If GITHUB_TOKEN is set, add the Authorization header:
+	if [ -n "$GITHUB_TOKEN" ]; then
+		headers+=("-H" "Authorization: token $GITHUB_TOKEN")
 	fi
+
+	# Determine the HTTP method and construct the curl command accordingly...
+	case "$method" in
+		GET)
+			curl -s "${headers[@]}" "$GITHUB_API_URL$endpoint"
+			;;
+		POST)
+			# For POST requests, always set the Content-Type header>
+			headers+=("-H" "Content-Type: application/json")
+
+			# If data is provided, include it in the request:
+			if [ -n "$data" ]; then
+				curl -s -X POST "${headers[@]}" -d "$data" "$GITHUB_API_URL$endpoint"
+			else
+				# Handle cases where POST data is required but not provided:
+				echo "POST request requires data."
+				on_error 1
+			fi
+			;;
+		*)
+			echo "Invalid HTTP method: $method"
+			on_error 1
+			;;
+	esac
 }
 
 # Main execution sequence.
@@ -103,6 +143,10 @@ main() {
 	pr_title=$(echo "$pr_details" | jq -r '.title')
 	pr_body=$(echo "$pr_details" | jq -r '.body // ""')
 	pr_url=$(echo "$pr_details" | jq -r '.html_url')
+	pr_author_login=$(echo "$pr_details" | jq -r '.user.login')
+
+	# Resolve the PR author's name and email using .mailmap:
+	pr_author_resolved=$(resolve_user "$pr_author_login")
 
 	# Extract reviewers:
 	pr_reviews=$(github_api "GET" "/repos/$REPO_OWNER/$REPO_NAME/pulls/$pr_number/reviews")
@@ -111,8 +155,51 @@ main() {
 	# Fetch commits in the PR:
 	pr_commits=$(github_api "GET" "/repos/$REPO_OWNER/$REPO_NAME/pulls/$pr_number/commits")
 
-	# Extract co-authors from commits:
-	co_authors=$(echo "$pr_commits" | jq -r '.[].commit.message' | grep -Eio "Co-authored-by:.*" | sort -u)
+	# Extract co-authors from commit messages:
+	processed_co_authors=""
+	while IFS= read -r co_author_line; do
+		name_email=$(echo "$co_author_line" | sed -E 's/Co-authored-by:[[:space:]]*(.*)/\1/')
+		name=$(echo "$name_email" | sed -E 's/^(.*)<.*>$/\1/' | xargs)
+		email=$(echo "$name_email" | sed -E 's/^.*<(.*)>$/\1/' | xargs)
+		resolved_author=$(resolve_name_email "$name" "$email")
+
+		processed_co_authors+="Co-authored-by: $resolved_author"$'\n'
+	done <<< "$co_authors"
+
+	# Extract commit authors:
+	authors_info=$(echo "$pr_commits" | jq -r '.[] | .commit.author | "\(.name) <\(.email)>"' | sort -u | sed '/^ *<.*>/d' | sed '/^$/d')
+
+	# Process commit authors:
+	commit_authors=""
+	while IFS= read -r author_line; do
+		# Skip empty lines:
+		if [ -z "$author_line" ]; then
+			continue
+		fi
+
+		# Extract name and email:
+		name=$(echo "$author_line" | sed -E 's/^(.*)<.*>$/\1/' | xargs)
+		email=$(echo "$author_line" | sed -E 's/^.*<(.*)>$/\1/' | xargs)
+
+		# Resolve name and email using .mailmap:
+		resolved_author=$(resolve_name_email "$name" "$email")
+
+		# Skip if the resolved author matches the resolved PR author:
+		if [ "$resolved_author" == "$pr_author_resolved" ]; then
+			continue
+		fi
+
+		commit_authors+="$resolved_author"$'\n'
+	done <<< "$authors_info"
+
+	# Remove any empty lines and duplicates:
+	commit_authors=$(echo "$commit_authors" | sort -u | sed '/^$/d')
+
+	# Prefix with 'Co-authored-by: ':
+	commit_authors_formatted=$(echo "$commit_authors" | sed 's/^/Co-authored-by: /' | sort -u)
+
+	# Combine co-authors and commit authors:
+	all_co_authors=$(echo -e "$co_authors\n$commit_authors_formatted" | sort -u | sed '/^$/d')
 
 	# Extract 'Signed-off-by' lines from commits:
 	signed_off_bys=$(echo "$pr_commits" | jq -r '.[].commit.message' | grep -Eio 'Signed-off-by:.*' | sort -u)
@@ -124,6 +211,7 @@ main() {
 
 	# GitHub-supported closing keywords:
 	closing_keywords=("close" "closes" "closed" "fix" "fixes" "fixed" "resolve" "resolves" "resolved")
+
 	# Create a regex pattern from the keywords:
 	keywords_pattern=$(IFS='|'; echo "${closing_keywords[*]}")
 
@@ -148,8 +236,8 @@ main() {
 		commit_body+="\n$ref_issues"
 	fi
 	commit_body+="\n"
-	if [ -n "$co_authors" ]; then
-		commit_body+="\n$co_authors"
+	if [ -n "$all_co_authors" ]; then
+		commit_body+="\n$all_co_authors"
 	fi
 	for reviewer in $reviewers; do
 		resolved_reviewer=$(resolve_user "$reviewer")