Updates that support Sidekiq 6.5+

Some changes to Sidekiq internals require changes to how we pass
options to certain Sidekiq classes we inherit from. These changes
maintain backwards compatibility, but add some complexity to the
code.

lib/sidekiq/limit_fetch.rb

@@ -28,13 +28,18 @@ module Sidekiq::LimitFetch
     UnitOfWork.new(queue, job) if job
   end
 
+  def config
+    # Post 6.5, Sidekiq.options is deprecated and replaced with passing Sidekiq directly
+    post_6_5? ? Sidekiq : Sidekiq.options
+  end
+
   # Backwards compatibility for sidekiq v6.1.0
   # @see https://github.com/mperham/sidekiq/pull/4602
   def bulk_requeue(*args)
     if Sidekiq::BasicFetch.respond_to?(:bulk_requeue) # < 6.1.0
       Sidekiq::BasicFetch.bulk_requeue(*args)
     else # 6.1.0+
-      Sidekiq::BasicFetch.new(Sidekiq.options).bulk_requeue(*args)
+      Sidekiq::BasicFetch.new(config).bulk_requeue(*args)
     end
   end
 
@@ -56,6 +61,10 @@ module Sidekiq::LimitFetch
 
   private
 
+  def post_6_5?
+    @post_6_5 ||= Gem::Version.new(Sidekiq::VERSION) >= Gem::Version.new('6.5.0')
+  end
+
   def redis_brpop(queues)
     if queues.empty?
       sleep TIMEOUT  # there are no queues to handle, so lets sleep

lib/sidekiq/limit_fetch/unit_of_work.rb

@@ -1,7 +1,11 @@
 module Sidekiq
   class LimitFetch::UnitOfWork < BasicFetch::UnitOfWork
     def initialize(queue, job)
-      super
+      if post_6_5?
+        super(queue, job, Sidekiq)
+      else
+        super
+      end
       redis_retryable { Queue[queue_name].increase_busy }
     end
 
@@ -17,6 +21,10 @@ module Sidekiq
 
     private
 
+    def post_6_5?
+      Gem::Version.new(Sidekiq::VERSION) >= Gem::Version.new('6.5.0')
+    end
+
     def redis_retryable(&block)
       Sidekiq::LimitFetch.redis_retryable(&block)
     end