perl - How to test that a method generating random numbers does generate random numbers -

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how can test method generating random numbers generates random numbers? there ($tested_method, rand) sort of syntax?

specifically, i'm referring ping generator method:

sub _create_ping_number {    ( $ping, @random_array );    $max            = 100000;    $random_counter = 0;     if ( $random_counter == $max ) {      @random_array   = ();      $random_counter = 0;    }     until ( !undef( $random_array[ $ping = int( rand($max) ) ] ) ) { }       $random_array[$ping] = 1;       $random_counter++;       return $ping; }

the links in comment mob provide detail on how difficult assert data source random.

for unit test, may better off using srand in test setup (making technically "white box" test), , relying on fact behaviour of rand() known. normal practice far know, unless want test prng or entropy source have written.


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