Remove commit-msg hook; improve version-bump script

scripts/hooks/README.md

@@ -1,18 +1,18 @@
 # Git Hooks
 
-A few hooks to ensure consistency and automation. Please setup the hooks if you contribute to pagy with PRs. 
+A hook to ensure consistency and automation. Please setup the hook if you contribute to pagy with PRs. 
+
+See also the brief description inside the hook file.
 
-See also the brief description inside each hook file.
-
 ## Setup
 
 ### Symlink
 
-Symlink the hooks into the `.git/hooks` dir:
+Symlink the hook into the `.git/hooks` dir:
 
 ```shell
 # from the repo root
-ln -s ../../scripts/hooks/{pre-commit,commit-msg} .git/hooks 
+ln -s ../../scripts/hooks/pre-commit .git/hooks 
 ```
 
 ### Copy
@@ -21,5 +21,5 @@ Only for filesystem that don't support symlinks: copy the hooks into the `.git/h
 
 ```shell
 # from the repo root
-cp scripts/hooks/{pre-commit,commit-msg} .git/hooks 
+cp scripts/hooks/pre-commit .git/hooks 
 ```

scripts/hooks/pre-commit

@@ -12,7 +12,7 @@ gem_changes=$(git diff --cached --name-status --relative=gem)
 if [[ -n "$gem_changes" ]]
 then
 	branch=$(git rev-parse --abbrev-ref HEAD)
-	if [[ $branch == master* ]]
+	if [[ "$branch" == master* ]]
 	then
 		cat <<-EOF
 			Error: The following changes in the "gem" root path

scripts/version-bump.sh

@@ -2,8 +2,8 @@
 
 set -e
 
-# Exit if the working tree is dirty
-test -n "$(git status --porcelain)" && echo "Working tree dirty!" && exit 1
+# Abort if the working tree is dirty
+[[ -z "$(git status --porcelain)" ]] || (>&2 echo "Working tree dirty!" && exit 1)
 
 # Set the root path
 dir="$(dirname -- "$0")"
@@ -15,10 +15,14 @@ old_vers=$(ruby -Igem/lib -rpagy -e 'puts Pagy::VERSION')
 echo "Current Pagy::VERSION: $old_vers"
 read -rp 'Enter the new version> ' new_vers
 
-# Check the new version
-[[ -z $new_vers ]] && echo 'Missing new version!' && exit 1
+# Abort if the version is invalid
+[[ -n $new_vers ]] || ( >&2 echo 'Missing new version!' && exit 1)
 num=$(echo "$new_vers" | grep -o '\.' | wc -l)
-[[ $num == 2 ]] || (echo 'Incomplete semantic version!' && exit 1)
+[[ $num == 2 ]] || (>&2 echo 'Incomplete semantic version!' && exit 1)
+
+# Abort if there is no gem change
+[[ -n $(git diff --name-only --relative=gem "$old_vers"..HEAD) ]] || \
+	(>&2 echo "No gem changes since version $old_vers!" && exit 1)
 
 # Bump version in files
 esc_old_vers=${old_vers//./\\.}
@@ -48,20 +52,22 @@ cd "$ROOT/src"
 pnpm run build
 cd "$ROOT"
 
-# Set TMPLOG to the commit messages marked as [GEM] (changes in the "gem" root path)
+# Set TMPLOG to the commit messages that have changes in the "gem" root path
 TMPLOG=$(mktemp)
 # Iterate through the new commits
 for commit in $(git rev-list "$old_vers"..HEAD)
 do
-	msg=$(git show --no-patch --format="%s%n%b" $commit)
-	if [[ $msg == \[GEM\]\ * ]]  # if gem changes
+	if [[ -n $(git show --pretty="format:" --name-only --relative=gem) ]]
 	then
-		sed 's/^/\ \ /; s/^\ \ \[GEM\]/-/' <<<"$msg" >> "$TMPLOG" # append to the temp file
+		git show --no-patch --format="- %s" $commit >> "$TMPLOG"
+		body=$(git show --no-patch --format="%b" $commit)
+		if [[ -n "$body" ]]
+		then
+			sed 's/^/\ \ /' <<<"$body" >> "$TMPLOG"
+		fi
 	fi
 done
 
-[[ -s "$TMPLOG" ]] || read -p 'The CHANGELOG is empty! (enter)> '
-
 # Insert the changes in the the release body file used by .github/workflows/create_release.yml
 # which is triggered by the :rubygem_release task (push tag)
 lead='^<!-- changes start -->$'