BUG: INCR

[LRagji]

Page https://redis.io/docs/latest/commands/incr

The page states return type of INCR & DECR is the integer number after incrementing, but when i do the following excersie around, the return value is garbled or overflows.

Steps to reproduce:

1. Take max of signed 64 bit number and deduct 1 from it = 9223372036854775807-1 = 9223372036854775806 (This is within specs of redis to increment).
2. set a 9223372036854775806
3. incr a
4. return 9223372036854776000 instead of 9223372036854775807
5. Same for decr

Not tested INCRby or DECRby

[dwdougherty]

Hi @LRagji. Thank you for reaching out. Here's what I'm seeing on Redis Open Source 8.2.1:

$ redis-cli
127.0.0.1:6379> set a 9223372036854775806
OK
127.0.0.1:6379> get a
"9223372036854775806"
127.0.0.1:6379> incr a
(integer) 9223372036854775807
127.0.0.1:6379> decr a
(integer) 9223372036854775806

Also, here's the raw RESP2 output (it is the same for RESP3):

set b 9223372036854775806
+OK
incr a
:9223372036854775807

The leading colon (:) indicates a return value of type integer.

All that said, my assessment is that the docs are correct. You have a couple of options:

1. Open a ticket in the redis/redis repo (the main source code repository for Redis Open Source).
2. Reach out on our Discord channel for further assistance. There are lots of friendly people there who can help.

[LRagji]

@dwdougherty can you try the same on the redis page itself, thats where the issue is.. https://redis.io/docs/latest/commands/incr

[dwdougherty]

Ah... I see. This client app has been known to have some edge case weirdness. I'll relay this to our DocOps person. Thanks for the report and followup.