From 84f1380f4830055bfe69ca14b5ade527a5edef6b Mon Sep 17 00:00:00 2001
From: Sebastien Bourdeauducq <sb@m-labs.hk>
Date: Sun, 19 Jul 2020 16:14:22 +0800
Subject: [PATCH] libasync: assert that callback consumes data in smoltcp recv

---
 libasync/src/smoltcp/tcp_stream.rs | 1 +
 1 file changed, 1 insertion(+)

diff --git a/libasync/src/smoltcp/tcp_stream.rs b/libasync/src/smoltcp/tcp_stream.rs
index c5bf991..f6846da 100644
--- a/libasync/src/smoltcp/tcp_stream.rs
+++ b/libasync/src/smoltcp/tcp_stream.rs
@@ -127,6 +127,7 @@ impl TcpStream {
                     socket.recv(|buf| {
                         if buf.len() > 0 {
                             let (amount, result) = (self.f)(buf);
+                            assert!(amount > 0);
                             (amount, Poll::Ready(Ok(result)))
                         } else {
                             (0, Poll::Pending)