Implement automatic Git hooks with Lefthook for code quality

- Replace manual hook installation with modular Lefthook configuration
- Check all changed files (staged + unstaged + untracked) for comprehensive coverage
- Add separate scripts in bin/lefthook/ for testability and maintainability
- Automatic installation via script/bootstrap and package.json postinstall
- Provide helpful error messages with fix commands and skip options
- Parallel execution of linting checks for performance

Prevents CI failures by catching linting issues locally before commits.

🤖 Generated with [Claude Code](https://claude.ai/code)

Co-Authored-By: Claude <[email protected]>

Author: justin808

.lefthook.yml

@@ -1,21 +1,21 @@
 # .lefthook.yml
-# Fast pre-commit hooks that only check changed files
+# Fast pre-commit hooks that check all changed files (staged + unstaged + untracked)
 # Install with: bundle exec lefthook install
 
 pre-commit:
   parallel: true
   commands:
     autofix:
-      run: bin/lefthook/ruby-autofix staged
+      run: bin/lefthook/ruby-autofix all-changed
 
     rubocop:
-      run: bin/lefthook/ruby-lint staged
+      run: bin/lefthook/ruby-lint all-changed
 
     prettier:
-      run: bin/lefthook/prettier-format staged
+      run: bin/lefthook/prettier-format all-changed
 
     trailing-newlines:
-      run: bin/lefthook/check-trailing-newlines staged
+      run: bin/lefthook/check-trailing-newlines all-changed
 
 pre-push:
   commands:

CLAUDE.md

@@ -12,15 +12,9 @@ This file provides guidance to Claude Code (claude.ai/code) when working with co
 
 These requirements are non-negotiable. CI will fail if not followed.
 
-**🚀 RECOMMENDED: Install Git hooks to automate these checks:**
+**🚀 AUTOMATIC: Git hooks are installed automatically during setup**
 
-```bash
-# Install Lefthook hooks (already included in Gemfile)
-bundle install
-bundle exec lefthook install
-```
-
-This will automatically run linting on **only the files you changed** before each commit - making it fast!
+Git hooks will automatically run linting on **all changed files (staged + unstaged + untracked)** before each commit - making it fast while preventing CI failures!
 
 **Note:** Git hooks are for React on Rails gem developers only, not for users who install the gem.
 

CONTRIBUTING.md

@@ -7,15 +7,9 @@
 ## Prerequisites
 
 - [Yalc](https://github.com/whitecolor/yalc) must be installed globally for most local development.
-- **Git hooks setup** (REQUIRED for all contributors):
+- **Git hooks setup** (automatic during normal setup):
 
-```sh
-cd react_on_rails/
-bundle install
-bundle exec lefthook install
-```
-
-This sets up automatic linting that runs **only on files you changed** - making commits fast while preventing CI failures.
+Git hooks are installed automatically when you run the standard setup commands. They will run automatic linting on **all changed files (staged + unstaged + untracked)** - making commits fast while preventing CI failures.
 
 - After updating code via Git, to prepare all examples:
 
@@ -492,10 +486,10 @@ rake lint
 
 - Format JavaScript/TypeScript files with Prettier (on changed files only)
 - Check and fix linting issues with ESLint
-- Check and fix Ruby style issues with RuboCop (on changed files only)
+- Check and fix Ruby style issues with RuboCop (on all changed files)
 - Ensure trailing newlines on all files
 
-**Setup once**: `bundle exec lefthook install` (see Prerequisites above)
+**Setup**: Automatic during normal development setup
 
 ## 🤖 Best Practices for AI Coding Agents
 

bin/lefthook/check-trailing-newlines

@@ -10,7 +10,11 @@ if [ -z "$files" ]; then
   exit 0
 fi
 
-echo "🔍 Checking trailing newlines on $CONTEXT files..."
+if [ "$CONTEXT" = "all-changed" ]; then
+  echo "🔍 Checking trailing newlines on all changed files..."
+else
+  echo "🔍 Checking trailing newlines on $CONTEXT files..."
+fi
 
 failed_files=""
 for file in $files; do

bin/lefthook/get-changed-files

@@ -9,14 +9,18 @@ case "$CONTEXT" in
   staged)
     git diff --cached --name-only --diff-filter=ACM | grep -E "$PATTERN" || true
     ;;
+  all-changed)
+    # Get all changed files (staged + unstaged + untracked) vs working directory
+    (git diff --cached --name-only --diff-filter=ACM; git diff --name-only --diff-filter=ACM; git ls-files --others --exclude-standard) | sort -u | grep -E "$PATTERN" || true
+    ;;
   branch)
     # Find base branch (prefer main over master)
     base="origin/main"
     git rev-parse --verify --quiet "$base" >/dev/null || base="origin/master"
     git diff --name-only --diff-filter=ACM "$base"...HEAD | grep -E "$PATTERN" || true
     ;;
   *)
-    echo "Usage: $0 {staged|branch} [pattern]" >&2
+    echo "Usage: $0 {staged|all-changed|branch} [pattern]" >&2
     exit 1
     ;;
 esac

bin/lefthook/prettier-format

@@ -10,13 +10,17 @@ if [ -z "$files" ]; then
   exit 0
 fi
 
-echo "💅 Prettier on $CONTEXT files:"
+if [ "$CONTEXT" = "all-changed" ]; then
+  echo "💅 Prettier on all changed files:"
+else
+  echo "💅 Prettier on $CONTEXT files:"
+fi
 printf "  %s\n" $files
 
 yarn run prettier --write $files
 
-# Re-stage files if running on staged context
-if [ "$CONTEXT" = "staged" ]; then
+# Re-stage files if running on staged or all-changed context
+if [ "$CONTEXT" = "staged" ] || [ "$CONTEXT" = "all-changed" ]; then
   echo $files | xargs -r git add
   echo "✅ Re-staged formatted files"
 fi

bin/lefthook/ruby-autofix

@@ -10,13 +10,17 @@ if [ -z "$files" ]; then
   exit 0
 fi
 
-echo "🎨 Autofix on $CONTEXT Ruby files:"
+if [ "$CONTEXT" = "all-changed" ]; then
+  echo "🎨 Autofix on all changed Ruby files:"
+else
+  echo "🎨 Autofix on $CONTEXT Ruby files:"
+fi
 printf "  %s\n" $files
 
 bundle exec rake autofix
 
-# Re-stage files if running on staged context
-if [ "$CONTEXT" = "staged" ]; then
+# Re-stage files if running on staged or all-changed context
+if [ "$CONTEXT" = "staged" ] || [ "$CONTEXT" = "all-changed" ]; then
   echo $files | xargs -r git add
   echo "✅ Re-staged formatted files"
 fi

bin/lefthook/ruby-lint

@@ -10,7 +10,11 @@ if [ -z "$files" ]; then
   exit 0
 fi
 
-echo "🔍 RuboCop on $CONTEXT Ruby files:"
+if [ "$CONTEXT" = "all-changed" ]; then
+  echo "🔍 RuboCop on all changed Ruby files:"
+else
+  echo "🔍 RuboCop on $CONTEXT Ruby files:"
+fi
 printf "  %s\n" $files
 
 if ! bundle exec rubocop --force-exclusion --display-cop-names -- $files; then

package.json

@@ -102,7 +102,8 @@
     "type-check": "yarn run tsc --noEmit --noErrorTruncation",
     "release:patch": "node_package/scripts/release patch",
     "release:minor": "node_package/scripts/release minor",
-    "release:major": "node_package/scripts/release major"
+    "release:major": "node_package/scripts/release major",
+    "postinstall": "test -f .lefthook.yml && test -d .git && command -v bundle >/dev/null 2>&1 && bundle exec lefthook install || true"
   },
   "repository": {
     "type": "git",

script/bootstrap

@@ -30,4 +30,10 @@ if [ -f "Gemfile" ]; then
   bundle check --path vendor/gems 2>&1 >/dev/null || {
     bundle install --path vendor/gems --quiet --without production
   }
+
+  # Install Git hooks for code quality (development only)
+  if [ -f ".lefthook.yml" ] && [ -d ".git" ]; then
+    echo "==> Installing Git hooks for code quality…"
+    bundle exec lefthook install
+  fi
 fi