var test = require('tape');
var Random = require('random-js');
var random = new Random(Random.engines.mt19937().seed(0));
var ss = require('../');

function rng() { return random.real(0, 1); }

test('shuffle', function(t) {
    var input = [1, 2, 3, 4, 5, 6];
    t.deepEqual(ss.shuffle([], rng), []);
    t.deepEqual(ss.shuffle(input, rng), [1, 5, 3, 2, 4, 6]);
    t.deepEqual(input, [1, 2, 3, 4, 5, 6], 'does not change original array');
    t.deepEqual(ss.shuffle(input, rng), [5, 4, 1, 3, 6, 2]);
    t.deepEqual(input, [1, 2, 3, 4, 5, 6], 'does not change original array');
    t.end();
});

test('shuffle_in_place', function(t) {
    var input = [1, 2, 3, 4, 5, 6];
    t.deepEqual(ss.shuffle_in_place([], rng), []);
    t.deepEqual(ss.shuffle_in_place(input, rng), [6, 1, 5, 2, 4, 3]);
    t.deepEqual(input, [6, 1, 5, 2, 4, 3], 'changes original array');
    t.end();
});