How to fix this error in 'to_ary' during the test run? [closed]

Redis::CommandError:                                                                                                  TestRun_1   |        ERR unknown command 'to_ary'TestRun_1   |      # /usr/local/bundle/gems/fakeredis-0.6.0/lib/fakeredis/command_executor.rb:12:in `write'TestRun_1   |      # /usr/local/bundle/gems/redis-3.3.3/lib/redis/client.rb:271:in `block in write'TestRun_1   |      # /usr/local/bundle/gems/redis-3.3.3/lib/redis/client.rb:250:in `io'TestRun_1   |      # /usr/local/bundle/gems/redis-3.3.3/lib/redis/client.rb:269:in `write'TestRun_1   |      # /usr/local/bundle/gems/redis-3.3.3/lib/redis/client.rb:228:in `block (3 levels) in process'TestRun_1   |      # /usr/local/bundle/gems/redis-3.3.3/lib/redis/client.rb:222:in `each'TestRun_1   |      # /usr/local/bundle/gems/redis-3.3.3/lib/redis/client.rb:222:in `block (2 levels) in process'TestRun_1   |      # /usr/local/bundle/gems/redis-3.3.3/lib/redis/client.rb:367:in `ensure_connected'TestRun_1   |      # /usr/local/bundle/gems/redis-3.3.3/lib/redis/client.rb:221:in `block in process'TestRun_1   |      # /usr/local/bundle/gems/redis-3.3.3/lib/redis/client.rb:306:in `logging'TestRun_1   |      # /usr/local/bundle/gems/redis-3.3.3/lib/redis/client.rb:220:in `process'TestRun_1   |      # /usr/local/bundle/gems/redis-3.3.3/lib/redis/client.rb:120:in `call'TestRun_1   |      # /usr/local/bundle/gems/redis-3.3.3/lib/redis.rb:2705:in `block in method_missing'TestRun_1   |      # /usr/local/bundle/gems/redis-3.3.3/lib/redis.rb:58:in `block in synchronize'TestRun_1   |      # /usr/local/bundle/gems/redis-3.3.3/lib/redis.rb:58:in `synchronize'TestRun_1   |      # /usr/local/bundle/gems/redis-3.3.3/lib/redis.rb:2704:in `method_missing'