depend or rely on getting something before one has it Don`t count your chickens before they`re hatched - remember you haven`t passed your exams yet and may not get the job you expect.
COUNT ONE`S CHICKENS BEFORE THEY`RE HATCHED
Meaning of COUNT ONE`S CHICKENS BEFORE THEY`RE HATCHED in English
English idioms vocab. Словарь английских идиом и выражений. 2012