add CI #2

	name: CI (Docker)

	on:
	push:
	branches: [ main, master ]
	pull_request:
	branches: [ main, master ]

	jobs:
	docker-test:
	name: Build Docker image and run tests (Ruby 3.3+)
	runs-on: ubuntu-latest
	steps:
	- name: Checkout repository
	uses: actions/checkout@v4

	- name: Build Docker image
	run: \|
	# Build image using the Dockerfile in the repo root. The image will contain Ruby 3.3 as in your Dockerfile.
	docker build -t ruby-libgd-ci:latest .

	- name: Run compile, build, install and tests inside container
	run: \|
	docker run --rm ruby-libgd-ci:latest bash -lc "
	set -e
	cd /app

	echo '--- compile native extension (ext/gd) ---'
	if [ -d ext/gd ]; then
	cd ext/gd
	make clean \|\| true
	# If you need custom flags for extconf.rb, you can add them here:
	# ruby extconf.rb --with-gdlib=/usr/local
	ruby extconf.rb
	make
	cd ../..
	else
	echo 'ext/gd not found; skipping native build step'
	fi

	echo '--- build and install gem from local source ---'
	if [ -f ruby-libgd.gemspec ]; then
	gem build ruby-libgd.gemspec
	gem_file=\$(ls ruby-libgd-*.gem 2>/dev/null \| sort -V \| tail -n 1 \|\| true)
	if [ -n \"\$gem_file\" ]; then
	gem install \"\$gem_file\" --force
	else
	echo 'Built gem not found' && exit 1
	fi
	else
	echo 'ruby-libgd.gemspec not found; cannot build gem' && exit 1
	fi

	echo '--- install test/dev gems globally and run specs against installed gem ---'
	gem install rspec chunky_png rake --no-document
	if [ -d spec ]; then
	rspec --format documentation
	else
	echo 'No spec directory found. Add specs under spec/ or update workflow.' && exit 78
	fi
	"

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