Add failing test

quinn/src/tests.rs

@@ -744,3 +744,44 @@ async fn two_datagram_readers() {
     assert!(*a == *b"one" || *b == *b"one");
     assert!(*a == *b"two" || *b == *b"two");
 }
+
+#[tokio::test]
+async fn finish_finished_stream_no_error() {
+    let _guard = subscribe();
+    let endpoint = endpoint();
+
+    let (client, server) = tokio::join!(
+        async { endpoint
+            .connect(endpoint.local_addr().unwrap(), "localhost")
+            .unwrap().await.unwrap() },
+        async { endpoint.accept().await.unwrap().await.unwrap() }
+    );
+
+    let client = async {
+        let (mut send_stream, mut recv_stream) = client.open_bi().await.unwrap();
+        send_stream.write_all(b"request").await.unwrap();
+
+        let mut buf = [0u8; 8];
+        recv_stream.read_exact(&mut buf).await.unwrap();
+
+        assert_eq!(&buf, b"response");
+
+        tokio::time::sleep(Duration::from_millis(100)).await; // Simulate some more processing of the response.
+
+        send_stream.finish().await.unwrap(); // Be a good citizen and close stream instead of dropping.
+    };
+
+    let server = async {
+        let (mut send_stream, mut recv_stream) = server.accept_bi().await.unwrap();
+
+        let mut buf = [0u8; 7];
+        recv_stream.read_exact(&mut buf).await.unwrap();
+
+        assert_eq!(&buf, b"request");
+
+        send_stream.write_all(b"response").await.unwrap();
+        send_stream.finish().await.unwrap();
+    };
+
+    tokio::join!(client, server);
+}