use futures::future;
use futures::stream;
use futures_test::{
assert_stream_pending, assert_stream_next, assert_stream_done,
};
use futures_test::future::FutureTestExt;
#[test]
fn unfold1() {
let mut stream = stream::unfold(0, |state| {
if state <= 2 {
future::ready(Some((state * 2, state + 1))).pending_once()
} else {
future::ready(None).pending_once()
}
});
assert_stream_pending!(stream);
assert_stream_next!(stream, 0);
assert_stream_pending!(stream);
assert_stream_next!(stream, 2);
assert_stream_pending!(stream);
assert_stream_next!(stream, 4);
assert_stream_pending!(stream);
assert_stream_done!(stream);
}