Don’t you wish!

don't you wish

You would like this to be the case. A: "Next year, I'm going to beat you for student council president." B: "Yeah, don't you wish!"
See also: wish
Farlex Dictionary of Idioms.

(Don’t) you wish!

exclam. I’m sure you wish it were true. There’s no school tomorrow? You wish!
McGraw-Hill's Dictionary of American Slang and Colloquial Expressions
See also:
  • don't you wish
  • Don't you wish!
  • you wish
  • you wish!
  • as you wish
  • wish (one) well
  • wish somebody/something well
  • wish
  • dying wish
  • wish on