net: add a unit test for res.end

This unit test exploits the fact that the server will
stay in half-closed state after `res.end()`
Thus, the parser will receive the second request
and will parse it, triggering another call of the
connection handler - but it won't be able
to respond since the connection has been closed
in this direction
The bugged version will force the socket closing
and won't receive the second request

Refs: #36205

test/parallel/test-https-end-rst.js

@@ -0,0 +1,31 @@
+'use strict';
+const common = require('../common');
+
+const http = require('http');
+const net = require('net');
+
+const data = 'hello';
+const server = http.createServer({}, common.mustCallAtLeast((req, res) => {
+  res.setHeader('content-length', data.length);
+  res.end(data);
+}, 2));
+
+server.listen(0, function() {
+  const options = {
+    host: '127.0.0.1',
+    port: server.address().port,
+    allowHalfOpen: true
+  };
+  const socket = net.connect(options, common.mustCall(() => {
+    socket.on('ready', common.mustCall(() => {
+      socket.write('GET /\n\n');
+      setTimeout(() => {
+        socket.write('GET /\n\n');
+        setTimeout(() => {
+          socket.destroy();
+          server.close();
+        }, common.platformTimeout(10));
+      }, common.platformTimeout(10));
+    }));
+  }));
+});