Invalid bulk length due to possbile wrong function call

Following issue: on a testing machine, we had the module in the latest 2.x version, everything was running fine. Using latest Drupal and latest Predis.

For testing purposes, I installed 3.2. Then I experienced an error saying:

Original
Predis\Response\ServerException: ERR Protocol error: invalid bulk length in Predis\Client->onErrorResponse() (line 367 of sites/all/libraries/predis/lib/Predis/Client.php).

Additional
Predis\Connection\ConnectionException: Error while reading line from the server. [tcp://localhost:6379] in Predis\Connection\AbstractConnection->onConnectionError() (line 146 of sites/all/libraries/predis/lib/Predis/Connection/AbstractConnection.php).

I stepped through the code and found the following issue: Investigating sites/all/libraries/predis/lib/Redis/Cache/Predis.php and looking at functions deleteByPrefix(), flush() and flushVolatile(). The call always looks like

$client->eval(self::EVAL_DELETE_{VOLATILE|PREFIX}, array(<some parameter> . '*'));

Now looking at the Predis provided implementation of "eval" as well as looking through the Redis docs. It states that it needs a number of arguments and then the arguments themselfs. When I googled for the error, I came accross this Predis issue https://github.com/nrk/predis/issues/88 stating that you cannot pass an array.

So what I did is changing the call signature to

$client->eval(self::EVAL_DELETE_{VOLATILE|PREFIX}, 0, <some parameter> . '*') ;

Note the "0" as well as the removal of array() for the argument itself. This seems to fix all issues I had. I am able to properly flush the caches, everything gets written/read again and I don't see any errors that seem to indicate any issues with that fix.

I'm not sure why this has happened to me or why nobody else has the issues. Either did I do something wrong with the setup or did I miss some configuration variable somewhere?

If this issue gets confirmed, I'm happy to create a patch.