parseInteger and parsePositive are incorrect on Int

[Riateche]

Steps to Reproduce

In REPL:

:module Data.String
the (Maybe Int) (parseInteger "1111111111111111111111111")

Expected Behavior

parseInteger should return Nothing if the input can't be represented as an Int.

Observed Behavior

It returns incorrect value: Just 8375319363688624583.

Same issue with parsePositive.