pcg_rand 0.10.0

extern crate pcg_rand;
extern crate rand;

use pcg_rand::seeds::PcgSeeder;
use pcg_rand::Pcg32Basic;
use rand::{distributions::Alphanumeric, Rng, SeedableRng};

#[test]
fn pcg_basic_unseeded() {
    let mut ra: Pcg32Basic = Pcg32Basic::new_unseeded();
    let mut rb: Pcg32Basic = Pcg32Basic::new_unseeded();
    assert_eq!(
        ra.sample_iter(&Alphanumeric).take(100).collect::<Vec<_>>(),
        rb.sample_iter(&Alphanumeric).take(100).collect::<Vec<_>>()
    );
}

#[test]
fn pcg_basic_seed_match() {
    let mut ra: Pcg32Basic = SeedableRng::from_seed(PcgSeeder::seed_with_stream(11, 12));
    let mut rb: Pcg32Basic = SeedableRng::from_seed(PcgSeeder::seed_with_stream(11, 12));
    assert_eq!(
        ra.sample_iter(&Alphanumeric).take(100).collect::<Vec<_>>(),
        rb.sample_iter(&Alphanumeric).take(100).collect::<Vec<_>>()
    );
}

#[test]
fn pcg_basic_seq_diff() {
    //Test a bad case same seed with just slightly different
    //sequences (They must be 2 apart because they get incremented to odd
    //numbers for generator properties)
    let mut ra: Pcg32Basic = SeedableRng::from_seed(PcgSeeder::seed_with_stream(11, 12));
    let mut rb: Pcg32Basic = SeedableRng::from_seed(PcgSeeder::seed_with_stream(11, 14));
    assert!(
        ra.sample_iter(&Alphanumeric).take(100).collect::<Vec<_>>()
            != rb.sample_iter(&Alphanumeric).take(100).collect::<Vec<_>>()
    );
}

#[test]
#[should_panic]
fn pcg_basic_seq_aliasing() {
    //Test a bad case same seed with just slightly different
    //sequences. These two end up being the same because 12 gets bumped
    //to 13 or the generator doesn't fill the entire range (needs a 1
    //in the lowest bit)
    //This is only a trait of PCGBasic not the other generators
    let mut ra: Pcg32Basic = SeedableRng::from_seed(PcgSeeder::seed_with_stream(11, 12));
    let mut rb: Pcg32Basic = SeedableRng::from_seed(PcgSeeder::seed_with_stream(11, 13));
    assert!(
        ra.sample_iter(&Alphanumeric).take(100).collect::<Vec<_>>()
            != rb.sample_iter(&Alphanumeric).take(100).collect::<Vec<_>>()
    );
}

#[test]
fn pcg_basic_seed_diff() {
    //Test a bad case same seed with just slightly different
    //seeds
    let mut ra: Pcg32Basic = SeedableRng::from_seed(PcgSeeder::seed_with_stream(11, 11));
    let mut rb: Pcg32Basic = SeedableRng::from_seed(PcgSeeder::seed_with_stream(12, 11));
    assert!(
        ra.sample_iter(&Alphanumeric).take(100).collect::<Vec<_>>()
            != rb.sample_iter(&Alphanumeric).take(100).collect::<Vec<_>>()
    );
}