getBuffer returns string when enableAutoPipelining is true

[adamnoakes]

Hi, firstly, thanks for releasing the new auto pipelining feature.

Whilst testing on my project, I noticed that getBuffer returns the result converted to string (rather than a Buffer) with enableAutoPipelining set to true. Is this expected/ a known limitation with the pipelining implementation?

[adamnoakes]

Been looking into this a bit further and seems to be caused by *Buffer commands being created with Buffer omitted
https://github.com/luin/ioredis/blob/master/lib/commander.ts#L65-L71

commands.forEach(function (commandName) {
  Commander.prototype[commandName] = generateFunction(commandName, "utf8");
  Commander.prototype[commandName + "Buffer"] = generateFunction(
    commandName,
    null
  );
});

This commandName value is then used for calling the command again from the pipeline
https://github.com/luin/ioredis/blob/master/lib/commander.ts#L110-151

...
    // Create a new pipeline and make sure it's scheduled
    return executeWithAutoPipelining(this, commandName, args, callback);
  };

At which point the context that it's the Buffer variant of the command (and encoding is null) is lost.

[mcollina]

cc @ShogunPanda

[ShogunPanda]

I checked the PR. It LGTM!

[laverdet]

+1