Pluginfy rubocop-sequel (#50)

This PR makes rubocop-sequel support RuboCop's Plugin feature.

It replaces the ad-hoc `Inject` with RuboCop plugins introduced in RuboCop 1.72.
Additionally, since RuboCop already requires Ruby 2.7 or higher as its runtime,
the `required_ruby_version` will be updated to 2.7.

Follow-up rubocop/rubocop#13792

.github/workflows/actions.yml

@@ -11,6 +11,8 @@ jobs:
           - 3.0
           - 3.1
           - 3.2
+          - 3.3
+          - 3.4
     steps:
       - uses: actions/checkout@v4
       - uses: ruby/setup-ruby@v1

.rubocop.yml

@@ -2,7 +2,7 @@ require:
   - rubocop-rspec
 
 AllCops:
-  TargetRubyVersion: 2.5
+  TargetRubyVersion: 2.7
   NewCops: enable
 
 # Offense count: 1

README.md

@@ -25,22 +25,25 @@ gem 'rubocop-sequel'
 Add to your `.rubocop.yml`.
 
 ```
-require: rubocop-sequel
+plugins: rubocop-sequel
 ```
 
 `rubocop` will now automatically load RuboCop Sequel
 cops alongside with the standard cops.
 
+> [!NOTE]
+> The plugin system is supported in RuboCop 1.72+. In earlier versions, use `require` instead of `plugins`.
+
 ### Command line
 
 ```bash
-rubocop --require rubocop-sequel
+rubocop --plugin rubocop-sequel
 ```
 
 ### Rake task
 
 ```ruby
 RuboCop::RakeTask.new do |task|
-  task.requires << 'rubocop-sequel'
+  task.plugins << 'rubocop-sequel'
 end
 ```

lib/rubocop-sequel.rb

@@ -3,9 +3,7 @@
 require 'rubocop'
 require 'rubocop/sequel'
 require 'rubocop/sequel/version'
-require 'rubocop/sequel/inject'
-
-RuboCop::Sequel::Inject.defaults!
+require 'rubocop/sequel/plugin'
 
 require_relative 'rubocop/cop/sequel/helpers/migration'
 

lib/rubocop/sequel/plugin.rb

@@ -0,0 +1,31 @@
+# frozen_string_literal: true
+
+require 'lint_roller'
+
+module RuboCop
+  module Sequel
+    # A plugin that integrates rubocop-sequel with RuboCop's plugin system.
+    class Plugin < LintRoller::Plugin
+      def about
+        LintRoller::About.new(
+          name: 'rubocop-sequel',
+          version: Version::STRING,
+          homepage: 'https://github.com/rubocop/rubocop-sequel',
+          description: 'Code style checking for Sequel.'
+        )
+      end
+
+      def supported?(context)
+        context.engine == :rubocop
+      end
+
+      def rules(_context)
+        LintRoller::Rules.new(
+          type: :path,
+          config_format: :rubocop,
+          value: Pathname.new(__dir__).join('../../../config/default.yml')
+        )
+      end
+    end
+  end
+end

rubocop-sequel.gemspec

@@ -14,8 +14,10 @@ Gem::Specification.new do |gem|
   gem.require_paths = ['lib']
   gem.version       = '0.3.8'
   gem.metadata['rubygems_mfa_required'] = 'true'
+  gem.metadata['default_lint_roller_plugin'] = 'RuboCop::Sequel::Plugin'
 
-  gem.required_ruby_version = '>= 2.5'
+  gem.required_ruby_version = '>= 2.7'
 
-  gem.add_dependency 'rubocop', '~> 1.0'
+  gem.add_dependency 'lint_roller', '~> 1.1'
+  gem.add_dependency 'rubocop', '~> 1.72.1'
 end