http: makes response.writeHead return the response

Fixes: #25935 PR-URL: #25974 Reviewed-By: Anna Henningsen <[email protected]> Reviewed-By: Luigi Pinca <[email protected]>

Author: qubyte

doc/api/http.md

@@ -1444,6 +1444,10 @@ the request body should be sent. See the [`'checkContinue'`][] event on
 <!-- YAML
 added: v0.1.30
 changes:
+ - version: REPLACEME
+ pr-url: https://github.com/nodejs/node/pull/25974
+ description: Return `this` from `writeHead()` to allow chaining with
+ `end()`.
  - version: v5.11.0, v4.4.5
  pr-url: https://github.com/nodejs/node/pull/6291
  description: A `RangeError` is thrown if `statusCode` is not a number in
@@ -1453,17 +1457,23 @@ changes:
 *`statusCode`{number}
 *`statusMessage`{string}
 *`headers`{Object}
+* Returns:{http.ServerResponse}
 
 Sends a response header to the request. The status code is a 3-digit HTTP
 status code, like `404`. The last argument, `headers`, are the response headers.
 Optionally one can give a human-readable `statusMessage` as the second
 argument.
 
+Returns a reference to the `ServerResponse`, so that calls can be chained.
+
 ```js
 constbody='hello world';
-response.writeHead(200,{
-'Content-Length':Buffer.byteLength(body),
-'Content-Type':'text/plain' });
+response
+ .writeHead(200,{
+'Content-Length':Buffer.byteLength(body),
+'Content-Type':'text/plain'
+ })
+ .end(body);
 ```
 
 This method must only be called once on a message and it must

lib/_http_server.js

@@ -268,6 +268,8 @@ function writeHead(statusCode, reason, obj){
 }
 
 this._storeHeader(statusLine,headers);
+
+returnthis;
 }
 
 // Docs-only deprecated: DEP0063

test/parallel/test-http-response-writehead-returns-this.js

@@ -0,0 +1,22 @@
+'use strict';
+require('../common');
+consthttp=require('http');
+constassert=require('assert');
+
+constserver=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');
+
+constchunks=[];
+
+res.on('data',(chunk)=>chunks.push(chunk));
+res.on('end',()=>{
+assert.strictEqual(Buffer.concat(chunks).toString(),'abc');
+server.close();
+});
+});
+});