MGET and MSET behaviour differs from ioredis

[kamilkijak]

mget() doesn't throw an error when for an empty array (which is the default behaviour in ioredis).

• ioredis

  var Redis = require('ioredis');
  var redis = new Redis();
  await redis.mget([]);
  // throws Uncaught ReplyError: ERR wrong number of arguments for 'mget' command

• ioredis-mock

  var Redis = require('ioredis-mock');
  var redis = new Redis();
  await redis.mget([]);
  // returns []

This library is used to mimic ioredis which means we should throw an error for an empty array (even though it's less intuitive in my opinion, there was a related discussion in https://github.com/luin/ioredis/issues/419).

There's an equivalent problem for mset().

[renatocron]

I observed an additional distinct behavior:

ioredis library accepts both mset(['key', 'value']) and mset(...['key', 'value']) as valid inputs. However, when I switched to using ioredis-mock, only the latter version worked correctly. The former method led to arbitrary number keys being erroneously written to the memory.