use futures::future::{Future, FutureObj, FutureExt}; use std::pin::Pin; use futures::task::{Context, Poll}; #[test] fn dropping_does_not_segfault() { FutureObj::new(async { String::new() }.boxed()); } #[test] fn dropping_drops_the_future() { let mut times_dropped = 0; struct Inc<'a>(&'a mut u32); impl Future for Inc<'_> { type Output = (); fn poll(self: Pin<&mut Self>, _: &mut Context<'_>) -> Poll<()> { unimplemented!() } } impl Drop for Inc<'_> { fn drop(&mut self) { *self.0 += 1; } } FutureObj::new(Inc(&mut times_dropped).boxed()); assert_eq!(times_dropped, 1); }