Your package rubygem-redis failed to build from source in current rawhide. http://koji.fedoraproject.org/koji/taskinfo?taskID=7003679 For details on mass rebuild see https://fedoraproject.org/wiki/Fedora_21_Mass_Rebuild
Created attachment 906374 [details] build.log
Created attachment 906376 [details] root.log
Created attachment 906377 [details] state.log
This is due to redis not supporting Minitest 5. I've submitted Minitest 5 support upstream here: https://github.com/redis/redis-rb/pull/445
Fixed with http://koji.fedoraproject.org/koji/buildinfo?buildID=537420