Use minor version '4.0' for publish/deploy-doc

Author: mokuzon

.github/workflows/deploy-doc.yml

@@ -19,7 +19,7 @@ jobs:
       - uses: actions/checkout@de0fac2e4500dabe0009e67214ff5f5447ce83dd # v6.0.2
       - uses: ruby/setup-ruby@19a43a6a2428d455dbd1b85344698725179c9d8c # v1.289.0
         with:
-          ruby-version: '3.4.8'
+          ruby-version: '4.0'
       - run: bundle install
       - name: Setup Pages
         uses: actions/configure-pages@983d7736d9b0ae728b81ab479565c72886d7745b # v5.0.0

.github/workflows/publish.yml

@@ -23,7 +23,7 @@ jobs:
       - uses: ruby/setup-ruby@19a43a6a2428d455dbd1b85344698725179c9d8c # v1.289.0
         with:
           bundler-cache: true
-          ruby-version: 3.4.8
+          ruby-version: '4.0'
       - name: Update version file with the release version
         run: |
           if [ "${{ github.event_name }}" == "workflow_dispatch" ]; then

spec/workflows/ruby_version_consistency_spec.rb

@@ -0,0 +1,51 @@
+require 'yaml'
+
+RSpec.describe "GitHub Actions workflow Ruby version consistency" do
+  let(:workflows_dir) { File.expand_path('../../.github/workflows', __dir__) }
+
+  let(:latest_matrix_version) do
+    pr_workflow = YAML.safe_load(
+      File.read(File.join(workflows_dir, 'pull_request.yml')),
+      permitted_classes: [Symbol]
+    )
+    versions = pr_workflow.dig('jobs', 'build', 'strategy', 'matrix', 'ruby')
+    expect(versions).not_to be_nil, "No ruby matrix found in pull_request.yml"
+    versions.map(&:to_s).max_by { |v| Gem::Version.new(v) }
+  end
+
+  let(:hardcoded_ruby_versions) do
+    versions = {}
+
+    Dir[File.join(workflows_dir, '*.yml')].each do |file|
+      workflow = YAML.safe_load(File.read(file), permitted_classes: [Symbol])
+      basename = File.basename(file)
+
+      next unless workflow['jobs']
+
+      workflow['jobs'].each do |job_name, job|
+        steps = job['steps'] || []
+        steps.each do |step|
+          next unless step.is_a?(Hash) && step.dig('with', 'ruby-version')
+
+          ruby_version = step['with']['ruby-version'].to_s
+          next if ruby_version.include?('${{')
+
+          versions["#{basename} -> #{job_name}"] = ruby_version
+        end
+      end
+    end
+
+    versions
+  end
+
+  it "uses the same Ruby version as the latest in pull_request.yml matrix" do
+    expect(hardcoded_ruby_versions).not_to be_empty,
+      "No hardcoded ruby-version found in workflows"
+
+    mismatched = hardcoded_ruby_versions.reject { |_, v| v == latest_matrix_version }
+    expect(mismatched).to be_empty,
+      "Expected all hardcoded ruby-version to be '#{latest_matrix_version}' " \
+      "(latest in pull_request.yml matrix), but found:\n" \
+      "#{mismatched.map { |k, v| "  #{k}: #{v}" }.join("\n")}"
+  end
+end