From 95b0eec8af9a7bbd6eaae35d0116b915ce34470e Mon Sep 17 00:00:00 2001
From: Stephen Carman <hntd187@users.noreply.github.com>
Date: Fri, 1 Feb 2019 15:54:06 -0500
Subject: [PATCH] sync: bounded channel can not have 0 size (#879)

---
 tokio-sync/src/mpsc/bounded.rs | 1 +
 tokio-sync/tests/mpsc.rs       | 6 ++++++
 2 files changed, 7 insertions(+)

diff --git a/tokio-sync/src/mpsc/bounded.rs b/tokio-sync/src/mpsc/bounded.rs
index f2954448e..9bbfe6770 100644
--- a/tokio-sync/src/mpsc/bounded.rs
+++ b/tokio-sync/src/mpsc/bounded.rs
@@ -111,6 +111,7 @@ pub struct RecvError(());
 /// }));
 /// ```
 pub fn channel<T>(buffer: usize) -> (Sender<T>, Receiver<T>) {
+    assert_eq!(buffer >= 1, true);
     let semaphore = (::semaphore::Semaphore::new(buffer), buffer);
     let (tx, rx) = chan::channel(semaphore);
 
diff --git a/tokio-sync/tests/mpsc.rs b/tokio-sync/tests/mpsc.rs
index 5b184d4e2..b7ecd9efe 100644
--- a/tokio-sync/tests/mpsc.rs
+++ b/tokio-sync/tests/mpsc.rs
@@ -65,6 +65,12 @@ fn send_recv_with_buffer() {
     assert!(val.is_none());
 }
 
+#[test]
+#[should_panic]
+fn buffer_gteq_one() {
+    mpsc::channel::<i32>(0);
+}
+
 #[test]
 fn send_recv_unbounded() {
     let (mut tx, mut rx) = mpsc::unbounded_channel::<i32>();