test: use random ports where possible

This helps to prevent issues where a failed test can keep a bound
socket open long enough to cause other tests to fail with EADDRINUSE
because the same port number is used.

PR-URL: https://github.com/nodejs/node/pull/7045
Reviewed-By: Ben Noordhuis <info@bnoordhuis.nl>
Reviewed-By: Matteo Collina <matteo.collina@gmail.com>
Reviewed-By: Rod Vagg <rod@vagg.org>

1 files changed, 2 insertions, 3 deletions

diff --git a/test/parallel/test-tls-alpn-server-client.js b/test/parallel/test-tls-alpn-server-client.js
index 35784511c4..0da2086f4d 100644
--- a/test/parallel/test-tls-alpn-server-client.js
+++ b/test/parallel/test-tls-alpn-server-client.js
@@ -24,7 +24,6 @@ function loadPEM(n) {
   return fs.readFileSync(filenamePEM(n));
 }
 
-var serverPort = common.PORT;
 var serverIP = common.localhostIPv4;
 
 function checkResults(result, expected) {
@@ -43,13 +42,13 @@ function runTest(clientsOptions, serverOptions, cb) {
     results[index].server = {ALPN: c.alpnProtocol, NPN: c.npnProtocol};
   });
 
-  server.listen(serverPort, serverIP, function() {
+  server.listen(0, serverIP, function() {
     connectClient(clientsOptions);
   });
 
   function connectClient(options) {
     var opt = options.shift();
-    opt.port = serverPort;
+    opt.port = server.address().port;
     opt.host = serverIP;
     opt.rejectUnauthorized = false;