zrevrangebyscore returns an empty array, but zrangebyscore is populated

[theycallmeswift]

I've encountered a strange bug where zrevrangebyscore returns an empty set, but zrangebyscore with the same parameters returns a set.

[28] pry(main)> REDIS.del("ncaa:event:1:leaderboard")
=> 1
[29] pry(main)> REDIS.zincrby("ncaa:event:1:leaderboard", 1, "Rutgers")
=> 1.0
[30] pry(main)> REDIS.zincrby("ncaa:event:1:leaderboard", 1, "Rutgers")
=> 2.0
[31] pry(main)> REDIS.zincrby("ncaa:event:1:leaderboard", 1, "CalTech")
=> 1.0
[32] pry(main)> REDIS.zincrby("ncaa:event:1:leaderboard", 1, "Rutgers")
=> 3.0
[33] pry(main)> REDIS.zincrby("ncaa:event:1:leaderboard", 1, "CalTech")
=> 2.0
[34] pry(main)> REDIS.zincrby("ncaa:event:1:leaderboard", 1, "TCNJ")
=> 1.0
[35] pry(main)> REDIS.zrevrangebyscore("ncaa:event:1:leaderboard", "1", "10", with_scores: true)
=> []
[36] pry(main)> REDIS.zrangebyscore("ncaa:event:1:leaderboard", "1", "10", with_scores: true)
=> [["TCNJ", 1.0], ["CalTech", 2.0], ["Rutgers", 3.0]]

System Info:

Ruby Version: 2.1.1 Redis Version: 2.8.7 Library Version: 3.0.7

[yaauie]

Per the documentation of the underlying command, your agruments are in the wrong order; max comes before min.

 ZREVRANGEBYSCORE key max min [WITHSCORES] [LIMIT offset count] 

In the future, please try running your commands with redis directly before reporting an issue with this client library; here is a reproduction in redis-cli:

╭─{ yaauie @ beorn in ~ }
╰─○ redis-cli
redis 127.0.0.1:6379> zincrby ncaa:event:1:leaderboard 1 Rutgers
"1"
redis 127.0.0.1:6379> zincrby ncaa:event:1:leaderboard 1 Rutgers
"2"
redis 127.0.0.1:6379> zincrby ncaa:event:1:leaderboard 1 CalTech
"1"
redis 127.0.0.1:6379> zincrby ncaa:event:1:leaderboard 1 Rutgers
"3"
redis 127.0.0.1:6379> zincrby ncaa:event:1:leaderboard 1 CalTech
"2"
redis 127.0.0.1:6379> zincrby ncaa:event:1:leaderboard 1 TCNJ
"1"
redis 127.0.0.1:6379> zrevrangebyscore ncaa:event:1:leaderboard 1 10 WITHSCORES
(empty list or set)
redis 127.0.0.1:6379> zrangebyscore ncaa:event:1:leaderboard 1 10 WITHSCORES
1) "TCNJ"
2) "1"
3) "CalTech"
4) "2"
5) "Rutgers"
6) "3"
redis 127.0.0.1:6379> zrevrangebyscore ncaa:event:1:leaderboard 10 1 WITHSCORES
1) "Rutgers"
2) "3"
3) "CalTech"
4) "2"
5) "TCNJ"
6) "1"
redis 127.0.0.1:6379>