1
0
mirror of https://github.com/vlang/v.git synced 2023-08-10 21:13:21 +03:00
v/vlib/rand/util/util_test.v

58 lines
1.2 KiB
V
Raw Normal View History

import rand
import rand.util
fn test_sample_nr() {
lengths := [1, 3, 4, 5, 6, 7]
a := ['one', 'two', 'three', 'four', 'five', 'six', 'seven']
for length in lengths {
b := util.sample_nr(a, length)
assert b.len == length
for element in b {
assert element in a
// make sure every element occurs once
mut count := 0
for e in b {
if e == element {
count++
}
}
assert count == 1
}
}
}
fn test_sample_r() {
k := 20
a := ['heads', 'tails']
b := util.sample_r(a, k)
assert b.len == k
for element in b {
assert element in a
}
}
fn test_shuffle() {
rand.seed([u32(1), 2]) // set seed to produce same results in order
a := [1, 2, 3, 4, 5, 6, 7, 8, 9, 10]
mut b := a.clone()
mut c := a.clone()
util.shuffle(mut b, 0)
util.shuffle(mut c, 0)
assert b == [6, 4, 5, 1, 9, 2, 10, 3, 8, 7]
assert c == [1, 6, 5, 8, 7, 2, 10, 9, 3, 4]
// test shuffling a slice
mut d := a.clone()
util.shuffle(mut d[..5], 0)
assert d == [5, 2, 1, 3, 4, 6, 7, 8, 9, 10]
assert d[5..] == a[5..]
// test shuffling n items
mut e := a.clone()
util.shuffle(mut e, 5)
assert e[..5] == [10, 3, 1, 8, 4]
assert e[5..] == [6, 7, 5, 9, 2]
// test shuffling empty array
mut f := a[..0]
util.shuffle(mut f, 0)
assert f == []int{}
}