http: makes response.writeHead return the response

Fixes: https://github.com/nodejs/node/issues/25935

PR-URL: https://github.com/nodejs/node/pull/25974
Reviewed-By: Anna Henningsen <anna@addaleax.net>
Reviewed-By: Luigi Pinca <luigipinca@gmail.com>

1 files changed, 22 insertions, 0 deletions

diff --git a/test/parallel/test-http-response-writehead-returns-this.js b/test/parallel/test-http-response-writehead-returns-this.js
new file mode 100644
index 00000000000..a62c2eca035
--- /dev/null
+++ b/test/parallel/test-http-response-writehead-returns-this.js
@@ -0,0 +1,22 @@
+'use strict';
+require('../common');
+const http = require('http');
+const assert = require('assert');
+
+const server = http.createServer((req, res) => {
+  res.writeHead(200, { 'a-header': 'a-header-value' }).end('abc');
+});
+
+server.listen(0, () => {
+  http.get({ port: server.address().port }, (res) => {
+    assert.strictEqual(res.headers['a-header'], 'a-header-value');
+
+    const chunks = [];
+
+    res.on('data', (chunk) => chunks.push(chunk));
+    res.on('end', () => {
+      assert.strictEqual(Buffer.concat(chunks).toString(), 'abc');
+      server.close();
+    });
+  });
+});