test,net: add tests for server.connections

There were no tests confirming situations where server.connections
should return `null`. Add a test for that situation.

Expand existing server.connection test slightly to check value.

Refactor (mostly spacing) code for server.connections setter.

PR-URL: https://github.com/nodejs/node/pull/10762
Reviewed-By: James M Snell <jasnell@gmail.com>

1 files changed, 10 insertions, 4 deletions

diff --git a/test/parallel/test-net-server-connections.js b/test/parallel/test-net-server-connections.js
index 7ee1df1a54..01e535803a 100644
--- a/test/parallel/test-net-server-connections.js
+++ b/test/parallel/test-net-server-connections.js
@@ -1,12 +1,18 @@
 'use strict';
-require('../common');
+const common = require('../common');
 const assert = require('assert');
 
 const net = require('net');
 
-// test that server.connections property is no longer enumerable now that it
-// has been marked as deprecated
-
 const server = new net.Server();
 
+const expectedWarning = 'Server.connections property is deprecated. ' +
+                        'Use Server.getConnections method instead.';
+
+common.expectWarning('DeprecationWarning', expectedWarning);
+
+// test that server.connections property is no longer enumerable now that it
+// has been marked as deprecated
 assert.strictEqual(Object.keys(server).indexOf('connections'), -1);
+
+assert.strictEqual(server.connections, 0);