diff --git a/lib/sidekiq-unique-jobs.rb b/lib/sidekiq-unique-jobs.rb
index <HASH>..<HASH> 100644
--- a/lib/sidekiq-unique-jobs.rb
+++ b/lib/sidekiq-unique-jobs.rb
@@ -56,7 +56,7 @@ module SidekiqUniqueJobs
   end
 
   def redis_version
-    @redis_version ||= connection { |c| c.info('server')['redis_version'] }
+    @redis_version ||= connection { |c| c.info('server'.freeze)['redis_version'.freeze] }
   end
 
   def connection(redis_pool = nil)
@@ -67,10 +67,6 @@ module SidekiqUniqueJobs
     end
   end
 
-  def mock_redis
-    @redis_mock ||= MockRedis.new if defined?(MockRedis)
-  end
-
   def synchronize(item, redis_pool)
     Lock::WhileExecuting.synchronize(item, redis_pool) { yield }
   end
Remove mock_redis completely

Not in use anymore