buf: stream and iter helpers (#1011)

tokio-buf/tests/stream.rs

@@ -0,0 +1,49 @@
+extern crate bytes;
+extern crate futures;
+extern crate tokio_buf;
+extern crate tokio_mock_task;
+
+use futures::sync::mpsc;
+use futures::Async::*;
+use std::io::Cursor;
+use tokio_buf::{util, BufStream};
+use tokio_mock_task::MockTask;
+
+#[macro_use]
+mod support;
+
+type Buf = Cursor<&'static [u8]>;
+
+#[test]
+fn empty_stream() {
+    let (_, rx) = mpsc::unbounded::<Buf>();
+    let mut bs = util::stream(rx);
+    assert_none!(bs.poll_buf());
+}
+
+#[test]
+fn full_stream() {
+    let (tx, rx) = mpsc::unbounded();
+    let mut bs = util::stream(rx);
+    let mut task = MockTask::new();
+
+    tx.unbounded_send(buf(b"one")).unwrap();
+
+    assert_buf_eq!(bs.poll_buf(), "one");
+    task.enter(|| assert_not_ready!(bs.poll_buf()));
+
+    tx.unbounded_send(buf(b"two")).unwrap();
+
+    assert!(task.is_notified());
+    assert_buf_eq!(bs.poll_buf(), "two");
+    task.enter(|| assert_not_ready!(bs.poll_buf()));
+
+    drop(tx);
+
+    assert!(task.is_notified());
+    assert_none!(bs.poll_buf());
+}
+
+fn buf(data: &'static [u8]) -> Buf {
+    Cursor::new(data)
+}