Will we ever get a Sandbox/Practice mode?

A mode where you can adjust your level, reset the map, buy items for free, raise your CDR or reset skill CD's manually, load in a different champion and so on.

Will we ever get this? It would be a great way to practice very specific things, such as the power of item combinations or mastering a skill combo (like Headbutt/Pulverize or Petrifying Gaze/Flash). It'd also be great for duplicating a bug you encountered so you can record and submit it to be fixed.