import sync

struct Counter {
pub mut:
    i int
}

fn (mut c Counter) add(i int) {
    c.i = c.i + i
}

fn run(mut m sync.ManyTimes, mut co Counter, c chan bool) {
    m.do(fn [mut co] () {
        co.add(5)
    })
    c <- true
}

fn test_many_times_once() {
    mut co := &Counter{}
    mut m := sync.new_many_times(1)
    c := chan bool{}
    n := 10

    // It is executed 10 times, but only once actually.
    for i := 0; i < n; i++ {
        spawn run(mut m, mut co, c)
    }
    for i := 0; i < n; i++ {
        <-c
    }
    assert co.i == 5
}

fn test_many_times_fifth() {
    mut co := &Counter{}
    mut m := sync.new_many_times(5)
    c := chan bool{}
    n := 10

    // It is executed 10 times, but only 5 times actually.
    for i := 0; i < n; i++ {
        spawn run(mut m, mut co, c)
    }
    for i := 0; i < n; i++ {
        <-c
    }
    assert co.i == 25
}