From 50ae892d5e38d643523a9c4ff46ef27c374f17e8 Mon Sep 17 00:00:00 2001
From: Alexander Simmerl <a.simmerl@gmail.com>
Date: Mon, 19 Mar 2018 20:35:12 +0100
Subject: [PATCH] p2p: Keep reference to connections in test peer

We observed non-deterministic test failures in one of our switch tests,
which would happen if the GC would run between iterations of the accept
loop. As we don't hold any reference to the connection the setup
finalizer might get triggered and therefore the file handle closed. For
the curious check the references on finalizers and the variable scoping
in the spec:

https://groups.google.com/forum/#!topic/golang-nuts/xWkhGJ5PY6c
https://groups.google.com/forum/#!topic/golang-nuts/d8aF4rAob7U/discussion
https://golang.org/ref/spec#Declarations_and_scope

Fixes #1266
---
 p2p/peer_test.go | 11 +++++++++--
 1 file changed, 9 insertions(+), 2 deletions(-)

diff --git a/p2p/peer_test.go b/p2p/peer_test.go
index 45e2b0457..0bf7076e1 100644
--- a/p2p/peer_test.go
+++ b/p2p/peer_test.go
@@ -140,6 +140,8 @@ func (p *remotePeer) Stop() {
 }
 
 func (p *remotePeer) accept(l net.Listener) {
+	conns := []net.Conn{}
+
 	for {
 		conn, err := l.Accept()
 		if err != nil {
@@ -160,10 +162,15 @@ func (p *remotePeer) accept(l net.Listener) {
 		if err != nil {
 			golog.Fatalf("Failed to perform handshake: %+v", err)
 		}
+
+		conns = append(conns, conn)
+
 		select {
 		case <-p.quit:
-			if err := conn.Close(); err != nil {
-				golog.Fatal(err)
+			for _, conn := range conns {
+				if err := conn.Close(); err != nil {
+					golog.Fatal(err)
+				}
 			}
 			return
 		default: