refactor: Extract retrieve_work patch

This should help DRY-up ixti#175

lib/sidekiq/throttled/patches/basic_fetch.rb

@@ -3,25 +3,14 @@
 require "sidekiq"
 require "sidekiq/fetch"
 
+require_relative "./throttled_retriever"
+
 module Sidekiq
   module Throttled
     module Patches
       module BasicFetch
-        # Retrieves job from redis.
-        #
-        # @return [Sidekiq::Throttled::UnitOfWork, nil]
-        def retrieve_work
-          work = super
-
-          if work && Throttled.throttled?(work.job)
-            Throttled.cooldown&.notify_throttled(work.queue)
-            requeue_throttled(work)
-            return nil
-          end
-
-          Throttled.cooldown&.notify_admitted(work.queue) if work
-
-          work
+        def self.prepended(base)
+          base.prepend(ThrottledRetriever)
         end
 
         private

lib/sidekiq/throttled/patches/throttled_retriever.rb

@@ -0,0 +1,26 @@
+# frozen_string_literal: true
+
+module Sidekiq
+  module Throttled
+    module Patches
+      module ThrottledRetriever
+        # Retrieves job from redis.
+        #
+        # @return [Sidekiq::BasicFetch::UnitOfWork, nil]
+        def retrieve_work
+          work = super
+
+          if work && Throttled.throttled?(work.job)
+            Throttled.cooldown&.notify_throttled(work.queue)
+            requeue_throttled(work)
+            return nil
+          end
+
+          Throttled.cooldown&.notify_admitted(work.queue) if work
+
+          work
+        end
+      end
+    end
+  end
+end