CI: test against Rack v2 and v3

Author: orien

.github/workflows/test.yml

@@ -4,22 +4,27 @@ on: [push, pull_request]
 
 jobs:
   test:
+    name: Test (Ruby ${{ matrix.ruby }}, Rack ${{ matrix.rack }})
     runs-on: "ubuntu-latest"
     continue-on-error: ${{ matrix.experimental }}
     strategy:
       fail-fast: false
       matrix:
-        ruby_version: ["2.6", "2.7", "3.0", "3.1", "3.2", "3.3", "3.4", "4.0"]
+        ruby: ["2.6", "2.7", "3.0", "3.1", "3.2", "3.3", "3.4", "4.0"]
+        rack: ["2", "3"]
         experimental: [false]
         include:
-          - ruby_version: "ruby-head"
+          - ruby: "ruby-head"
+            rack: "3"
             experimental: true
+    env:
+      RACK_VERSION: ${{ matrix.rack }}
 
     steps:
       - uses: actions/checkout@v6
       - uses: ruby/setup-ruby@v1
         with:
-          ruby-version: ${{ matrix.ruby_version }}
+          ruby-version: ${{ matrix.ruby }}
           bundler-cache: true
       - run: "bundle exec rubocop lib/ spec/"
       - run: "bundle exec rspec spec/ -b"

Gemfile

@@ -8,7 +8,7 @@ group :development do
 end
 
 group :test do
-  gem 'rack', '~> 2'
+  gem 'rack', "~> #{ENV["RACK_VERSION"] || "3"}"
   gem 'rack-test', '~> 2'
   gem 'rspec', '~> 3.0', '>= 3.6.0'
   gem 'rspec-its', '~> 1.2'