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-rw-r--r--vendor/futures-channel/tests/mpsc-size_hint.rs40
1 files changed, 40 insertions, 0 deletions
diff --git a/vendor/futures-channel/tests/mpsc-size_hint.rs b/vendor/futures-channel/tests/mpsc-size_hint.rs
new file mode 100644
index 000000000..d9cdaa31f
--- /dev/null
+++ b/vendor/futures-channel/tests/mpsc-size_hint.rs
@@ -0,0 +1,40 @@
+use futures::channel::mpsc;
+use futures::stream::Stream;
+
+#[test]
+fn unbounded_size_hint() {
+ let (tx, mut rx) = mpsc::unbounded::<u32>();
+ assert_eq!((0, None), rx.size_hint());
+ tx.unbounded_send(1).unwrap();
+ assert_eq!((1, None), rx.size_hint());
+ rx.try_next().unwrap().unwrap();
+ assert_eq!((0, None), rx.size_hint());
+ tx.unbounded_send(2).unwrap();
+ tx.unbounded_send(3).unwrap();
+ assert_eq!((2, None), rx.size_hint());
+ drop(tx);
+ assert_eq!((2, Some(2)), rx.size_hint());
+ rx.try_next().unwrap().unwrap();
+ assert_eq!((1, Some(1)), rx.size_hint());
+ rx.try_next().unwrap().unwrap();
+ assert_eq!((0, Some(0)), rx.size_hint());
+}
+
+#[test]
+fn channel_size_hint() {
+ let (mut tx, mut rx) = mpsc::channel::<u32>(10);
+ assert_eq!((0, None), rx.size_hint());
+ tx.try_send(1).unwrap();
+ assert_eq!((1, None), rx.size_hint());
+ rx.try_next().unwrap().unwrap();
+ assert_eq!((0, None), rx.size_hint());
+ tx.try_send(2).unwrap();
+ tx.try_send(3).unwrap();
+ assert_eq!((2, None), rx.size_hint());
+ drop(tx);
+ assert_eq!((2, Some(2)), rx.size_hint());
+ rx.try_next().unwrap().unwrap();
+ assert_eq!((1, Some(1)), rx.size_hint());
+ rx.try_next().unwrap().unwrap();
+ assert_eq!((0, Some(0)), rx.size_hint());
+}