Restore injection for old rubocop versions

Gemfile.lock

@@ -3,7 +3,7 @@ PATH
   specs:
     rubocop-sorbet (0.9.0)
       lint_roller (~> 1.1)
-      rubocop (>= 1.72.1)
+      rubocop (>= 1)
 
 GEM
   remote: https://rubygems.org/

lib/rubocop-sorbet.rb

@@ -6,4 +6,9 @@
 require_relative "rubocop/sorbet/version"
 require_relative "rubocop/sorbet/plugin"
 
+if Gem::Version.create(RuboCop::Version.version) < RuboCop::Sorbet::Plugin::RUBOCOP_MIN_VERSION
+  require_relative "rubocop/sorbet/inject"
+  RuboCop::Sorbet::Inject.defaults!
+end
+
 require_relative "rubocop/cop/sorbet_cops"

lib/rubocop/sorbet.rb

@@ -1,10 +1,23 @@
 # frozen_string_literal: true
 
+require "rubocop"
 require "rubocop/sorbet/version"
+require "rubocop/sorbet/plugin"
+require "pathname"
 require "yaml"
 
 module RuboCop
   module Sorbet
     class Error < StandardError; end
+
+    unless Plugin::SUPPORTED
+      PROJECT_ROOT   = Pathname.new(__dir__).parent.parent.expand_path.freeze
+      CONFIG_DEFAULT = PROJECT_ROOT.join("config", "default.yml").freeze
+      CONFIG         = YAML.safe_load(CONFIG_DEFAULT.read).freeze
+
+      private_constant(:CONFIG_DEFAULT, :PROJECT_ROOT)
+
+      ::RuboCop::ConfigObsoletion.files << PROJECT_ROOT.join("config", "obsoletion.yml")
+    end
   end
 end

lib/rubocop/sorbet/inject.rb

@@ -0,0 +1,30 @@
+# frozen_string_literal: true
+
+# The original code is from https://github.com/rubocop-hq/rubocop-rspec/blob/master/lib/rubocop/rspec/inject.rb
+# See https://github.com/rubocop-hq/rubocop-rspec/blob/master/MIT-LICENSE.md
+module RuboCop
+  module Sorbet
+    # Because RuboCop doesn't yet support plugins, we have to monkey patch in a
+    # bit of our configuration.
+    module Inject
+      class << self
+        def defaults!
+          path = CONFIG_DEFAULT.to_s
+          hash = ConfigLoader.send(:load_yaml_configuration, path)
+          if Gem::Version.new(RuboCop::Version::STRING) >= Gem::Version.new("1.66")
+            # We use markdown for cop documentation. Unconditionally setting
+            # the base url will produce incorrect urls on older RuboCop versions,
+            # so we do that for fully supported version only here.
+            hash["Sorbet"] ||= {}
+            hash["Sorbet"]["DocumentationBaseURL"] = "https://github.com/Shopify/rubocop-sorbet/blob/main/manual"
+            hash["Sorbet"]["DocumentationExtension"] = ".md"
+          end
+          config = Config.new(hash, path).tap(&:make_excludes_absolute)
+          puts "configuration from #{path}" if ConfigLoader.debug?
+          config = ConfigLoader.merge_with_default(config, path)
+          ConfigLoader.instance_variable_set(:@default_configuration, config)
+        end
+      end
+    end
+  end
+end

lib/rubocop/sorbet/plugin.rb

@@ -1,11 +1,16 @@
 # frozen_string_literal: true
 
+require "rubocop"
 require "lint_roller"
+require "pathname"
 
 module RuboCop
   module Sorbet
     # A plugin that integrates RuboCop Sorbet with RuboCop's plugin system.
     class Plugin < LintRoller::Plugin
+      RUBOCOP_MIN_VERSION = '1.72.1'
+      SUPPORTED = Gem::Version.create(RuboCop::Version.version) < RUBOCOP_MIN_VERSION
+
       def about
         LintRoller::About.new(
           name: 'rubocop-sorbet',

rubocop-sorbet.gemspec

@@ -28,6 +28,6 @@ Gem::Specification.new do |spec|
   spec.executables   = spec.files.grep(%r{^exe/}) { |f| File.basename(f) }
   spec.require_paths = ["lib"]
 
-  spec.add_runtime_dependency("rubocop", ">= 1.72.1")
+  spec.add_runtime_dependency("rubocop", ">= 1")
   spec.add_runtime_dependency("lint_roller", "~> 1.1")
 end