http: fix res emit close before user finish

PR-URL: nodejs#20941
Reviewed-By: James M Snell <jasnell@gmail.com>
Reviewed-By: Matteo Collina <matteo.collina@gmail.com>
Reviewed-By: Ruben Bridgewater <ruben@bridgewater.de>

lib/_http_server.js

@@ -562,7 +562,7 @@ function resOnFinish(req, res, socket, state, server) {
 
   res.detachSocket(socket);
   req.emit('close');
-  res.emit('close');
+  process.nextTick(emitCloseNT, res);
 
   if (res._last) {
     if (typeof socket.destroySoon === 'function') {
@@ -585,6 +585,10 @@ function resOnFinish(req, res, socket, state, server) {
   }
 }
 
+function emitCloseNT(self) {
+  self.emit('close');
+}
+
 // The following callback is issued after the headers have been read on a
 // new message. In this callback we setup the response object and pass it
 // to the user.

test/parallel/test-http-req-res-close.js

@@ -2,12 +2,21 @@
 
 const common = require('../common');
 const http = require('http');
+const assert = require('assert');
 
 const server = http.Server(common.mustCall((req, res) => {
+  let resClosed = false;
+
   res.end();
-  res.on('finish', common.mustCall());
-  res.on('close', common.mustCall());
-  req.on('close', common.mustCall());
+  res.on('finish', common.mustCall(() => {
+    assert.strictEqual(resClosed, false);
+  }));
+  res.on('close', common.mustCall(() => {
+    resClosed = true;
+  }));
+  req.on('close', common.mustCall(() => {
+    assert.strictEqual(req._readableState.ended, true);
+  }));
   res.socket.on('close', () => server.close());
 }));