v/vlib/sync/once_with_param_test.v

40 lines
717 B
V

import sync
// Note: this is the same test as `vlib/sync/once_test.v`, but
// it uses an explicit passing of the voidptr parameter in
// once.do_with_param/2, instead of passing a closure of it
// in once.do/1.
// Closures are not yet implemented on Windows.
struct One {
pub mut:
i int
}
fn (mut o One) add(i int) {
o.i = o.i + i
}
fn run(mut once sync.Once, mut o One, c chan bool) {
once.do_with_param(fn (mut o One) {
o.add(5)
}, o)
c <- true
}
fn test_once() {
mut o := &One{}
mut once := sync.new_once()
c := chan bool{}
n := 10
// It is executed 10 times, but only once actually.
for i := 0; i < n; i++ {
go run(mut once, mut o, c)
}
for i := 0; i < n; i++ {
<-c
}
assert o.i == 5
}