CI: Reduce duplication by having extra gemfiles

.github/workflows/main.yml

@@ -35,94 +35,32 @@ jobs:
           - "3.4"
           - ruby-head
           - jruby-9.4
+        gemfile: [Gemfile]
         task:
           - internal_investigation
           - spec
+        include:
+          - {ruby: "3.4", gemfile: "gemfiles/oldest_rubocop.rb", task: spec}
+          - {ruby: "3.4", gemfile: "gemfiles/latest_rubocop.rb", task: internal_investigation}
+          - {ruby: "3.4", gemfile: "gemfiles/latest_rubocop.rb", task: spec}
+          - {ruby: "3.4", gemfile: "gemfiles/latest_rspec_4.rb", task: spec}
     name: "Ruby ${{ matrix.ruby }}: ${{ matrix.task }}"
+    env:
+      BUNDLE_GEMFILE: ${{ matrix.gemfile }}
     steps:
       - uses: actions/checkout@v5
       - uses: ruby/setup-ruby@v1
         with:
           ruby-version: "${{ matrix.ruby }}"
           bundler-cache: true
-      - run: NO_COVERAGE=true bundle exec rake ${{ matrix.task }}
-
-  coverage:
-    runs-on: ubuntu-latest
-    name: "Test coverage"
-    steps:
-      - uses: actions/checkout@v5
-      - uses: ruby/setup-ruby@v1
-        with:
-          ruby-version: "3.4"
-          bundler-cache: true
-      - run: bundle exec rake spec
-
-  edge-rubocop:
-    runs-on: ubuntu-latest
-    strategy:
-      matrix:
-        task:
-          - internal_investigation
-          - spec
-    name: "Edge RuboCop: ${{ matrix.task }}"
-    steps:
-      - uses: actions/checkout@v5
-      - name: Use latest RuboCop from `master`
-        run: |
-          echo "gem 'rubocop', github: 'rubocop/rubocop'" > Gemfile.local
-          cat Gemfile.local
-      - uses: ruby/setup-ruby@v1
-        with:
-          ruby-version: "3.4"
-          bundler-cache: true
+      - name: Show Gemfile for debugging
+        if: ${{ matrix.gemfile }} != Gemfile
+        run: cat $BUNDLE_GEMFILE
       - name: Show RuboCop version
-        run: grep '^    rubocop' Gemfile.lock | sort
+        if: ${{ matrix.gemfile }} != Gemfile
+        run: grep '^    rubocop' $BUNDLE_GEMFILE.lock | sort
       - run: NO_COVERAGE=true bundle exec rake ${{ matrix.task }}
 
-  oldest-rubocop:
-    runs-on: ubuntu-latest
-    strategy:
-      matrix:
-        task:
-          - spec
-    name: "Oldest RuboCop: ${{ matrix.task }}"
-    steps:
-      - uses: actions/checkout@v5
-      - name: Use oldest RuboCop allowed by gemspec
-        run: |
-          sed -nr "s/ *spec.add_dependency 'rubocop'.*'>= ([0-9\.]+)'/gem 'rubocop', '= \1'/p" \
-            rubocop-rspec.gemspec > Gemfile.local
-          cat Gemfile.local
-      - uses: ruby/setup-ruby@v1
-        with:
-          ruby-version: "3.4"
-          bundler-cache: true
-      - name: Show RuboCop version
-        run: grep '^    rubocop' Gemfile.lock | sort
-      - run: NO_COVERAGE=true bundle exec rake ${{ matrix.task }}
-
-  rspec4:
-    runs-on: ubuntu-latest
-    name: RSpec 4
-    steps:
-      - uses: actions/checkout@v5
-      - name: Use latest RSpec 4 from `4-0-dev` branch
-        run: |
-          sed -e '/rspec/d' -i Gemfile
-          cat << EOF > Gemfile.local
-            gem 'rspec', github: 'rspec/rspec', branch: '4-0-dev'
-            gem 'rspec-core', github: 'rspec/rspec', branch: '4-0-dev'
-            gem 'rspec-expectations', github: 'rspec/rspec', branch: '4-0-dev'
-            gem 'rspec-mocks', github: 'rspec/rspec', branch: '4-0-dev'
-            gem 'rspec-support', github: 'rspec/rspec', branch: '4-0-dev'
-          EOF
-      - uses: ruby/setup-ruby@v1
-        with:
-          ruby-version: "3.4"
-          bundler-cache: true
-      - run: NO_COVERAGE=true bundle exec rake spec
-
   prism:
     runs-on: ubuntu-latest
     name: Prism

.gitignore

@@ -7,8 +7,9 @@ doc
 
 # bundler
 .bundle
-Gemfile.lock
-Gemfile.local
+/Gemfile.lock
+/Gemfile.local
+/gemfiles/*.lock
 
 # jeweler generated
 pkg

Gemfile

@@ -1,22 +1,6 @@
 # frozen_string_literal: true
 
-source 'https://rubygems.org'
-
-gemspec
-
-gem 'bump'
-gem 'rack'
-gem 'rake'
-gem 'rspec', '~> 3.11'
-gem 'rubocop-performance', '~> 1.24'
-gem 'rubocop-rake', '~> 0.7'
-gem 'simplecov', '>= 0.19'
-gem 'yard'
-
-# FIXME: Remove when the next prism version is released.
-if RUBY_VERSION < '3.0' || RUBY_ENGINE == 'jruby'
-  gem 'prism', '!= 1.5.0', '!= 1.5.1'
-end
+eval_gemfile('gemfiles/common.rb')
 
 local_gemfile = 'Gemfile.local'
 eval_gemfile(local_gemfile) if File.exist?(local_gemfile)

gemfiles/common.rb

@@ -0,0 +1,19 @@
+# frozen_string_literal: true
+
+source 'https://rubygems.org'
+
+gemspec path: '..'
+
+gem 'bump'
+gem 'rack'
+gem 'rake'
+gem 'rspec', '~> 3.11'
+gem 'rubocop-performance', '~> 1.24'
+gem 'rubocop-rake', '~> 0.7'
+gem 'simplecov', '>= 0.19'
+gem 'yard'
+
+# FIXME: Remove when the next prism version is released.
+if RUBY_VERSION < '3.0' || RUBY_ENGINE == 'jruby'
+  gem 'prism', '!= 1.5.0', '!= 1.5.1'
+end

gemfiles/latest_rspec_4.rb

@@ -0,0 +1,12 @@
+# frozen_string_literal: true
+
+# Use latest RSpec 4 from `4-0-dev` branch
+lines = File.readlines('gemfiles/common.rb')
+lines.delete_if { |line| line.include?('rspec') }
+eval_gemfile('common.rb', lines.join)
+
+gem 'rspec', github: 'rspec/rspec', branch: '4-0-dev'
+gem 'rspec-core', github: 'rspec/rspec', branch: '4-0-dev'
+gem 'rspec-expectations', github: 'rspec/rspec', branch: '4-0-dev'
+gem 'rspec-mocks', github: 'rspec/rspec', branch: '4-0-dev'
+gem 'rspec-support', github: 'rspec/rspec', branch: '4-0-dev'

gemfiles/latest_rubocop.rb

@@ -0,0 +1,6 @@
+# frozen_string_literal: true
+
+eval_gemfile('common.rb')
+
+# Use latest RuboCop from `master`
+gem 'rubocop', github: 'rubocop/rubocop'

gemfiles/oldest_rubocop.rb

@@ -0,0 +1,8 @@
+# frozen_string_literal: true
+
+eval_gemfile('common.rb')
+
+# Use oldest RuboCop allowed by gemspec
+gemspec = File.read('rubocop-rspec.gemspec')
+version = gemspec[/ *spec.add_dependency 'rubocop'.*'>= ([0-9.]+)'/, 1]
+gem 'rubocop', version