v/vlib/context/deadline_test.v

64 lines
1.4 KiB
V

import context
import time
const (
// a reasonable duration to block in an example
short_duration = 1 * time.millisecond
)
fn after(dur time.Duration) chan int {
dst := chan int{}
go fn (dur time.Duration, dst chan int) {
time.sleep(dur)
dst <- 0
}(dur, dst)
return dst
}
// This example passes a context with an arbitrary deadline to tell a blocking
// function that it should abandon its work as soon as it gets to it.
fn test_with_deadline() {
dur := time.now().add(short_duration)
ctx := context.with_deadline(context.background(), dur)
defer {
// Even though ctx will be expired, it is good practice to call its
// cancellation function in any case. Failure to do so may keep the
// context and its parent alive longer than necessary.
context.cancel(ctx)
}
after_ch := after(1 * time.second)
ctx_ch := ctx.done()
select {
_ := <-after_ch {
assert false
}
_ := <-ctx_ch {
assert true
}
}
}
// This example passes a context with a timeout to tell a blocking function that
// it should abandon its work after the timeout elapses.
fn test_with_timeout() {
// Pass a context with a timeout to tell a blocking function that it
// should abandon its work after the timeout elapses.
ctx := context.with_timeout(context.background(), short_duration)
defer {
context.cancel(ctx)
}
after_ch := after(1 * time.second)
ctx_ch := ctx.done()
select {
_ := <-after_ch {
assert false
}
_ := <-ctx_ch {
assert true
}
}
}