The Test::MockRandom module replaces random number generation with non-random
 number generation.
 .
 This perhaps ridiculous-seeming module was created to test routines that
 manipulate random numbers by providing a known output from rand. Given a
 list of seeds with srand, it will return each in turn. After seeded
 random numbers are exhausted, it will always return 0. Seed numbers must
 be of a form that meets the expected output from rand as called with no
 arguments -- i.e. they must be between 0 (inclusive) and 1 (exclusive).
 In order to facilitate generating and testing a nearly-one number, this
 module exports the function oneish, which returns a number just
 fractionally less than one.
 .
 Depending on how this module is called with use, it will export rand to
 a specified package (e.g. a class being tested) effectively overriding
 and intercepting calls in that package to the built-in rand. It can also
 override rand in the current package or even globally. In all of these
 cases, it also exports srand and oneish to the current package in order
 to control the output of rand.