async-hooks,net: ensure asyncId=null if no handle

If the .listen() hasn't been called on the server, there is no handle object. In this case use null as the triggerAsyncId. Fixes: #13548 PR-URL: #13938 Reviewed-By: James M Snell <[email protected]> Reviewed-By: Refael Ackermann <[email protected]> Reviewed-By: Trevor Norris <[email protected]> Reviewed-By: Andreas Madsen <[email protected]>

Author: Matt Sergeant

lib/net.js

@@ -1558,7 +1558,8 @@ Server.prototype.getConnections = function(cb){
 constself=this;
 
 functionend(err,connections){
-nextTick(self[async_id_symbol],cb,err,connections);
+constasyncId=self._handle ? self[async_id_symbol] : null;
+nextTick(asyncId,cb,err,connections);
 }
 
 if(!this._usingSlaves){

test/async-hooks/test-net-get-connections.js

@@ -0,0 +1,11 @@
+'use strict';
+
+constcommon=require('../common');
+constnet=require('net');
+constserver=net.createServer();
+
+// This test was based on an error raised by Haraka.
+// It caused server.getConnections to raise an exception.
+// Ref: https://github.com/haraka/Haraka/pull/1951
+
+server.getConnections(common.mustCall());