http: make OutgoingMessage more streamlike

Implement missing getters error & closed. Add support for
proper "writable" check through `isWritable` helper.
We cannot fix the `OutgoingMessage.writable` property as that
would break the ecosystem.
PR-URL: #45672
Reviewed-By: Matteo Collina <matteo.collina@gmail.com>
Reviewed-By: Gerhard Stöbich <deb2001-github@yahoo.de>
Reviewed-By: Minwoo Jung <nodecorelab@gmail.com>
Reviewed-By: Antoine du Hamel <duhamelantoine1995@gmail.com>

Author: ronag

lib/_http_outgoing.js

@@ -88,6 +88,7 @@ const kCorked = Symbol('corked');
 constkUniqueHeaders=Symbol('kUniqueHeaders');
 constkBytesWritten=Symbol('kBytesWritten');
 constkEndCalled=Symbol('kEndCalled');
+constkErrored=Symbol('errored');
 
 constnop=()=>{};
 
@@ -147,10 +148,26 @@ function OutgoingMessage() {
 this._keepAliveTimeout=0;
 
 this._onPendingData=nop;
+
+this[kErrored]=null;
 }
 ObjectSetPrototypeOf(OutgoingMessage.prototype,Stream.prototype);
 ObjectSetPrototypeOf(OutgoingMessage,Stream);
 
+ObjectDefineProperty(OutgoingMessage.prototype,'errored',{
+__proto__: null,
+get(){
+returnthis[kErrored];
+},
+});
+
+ObjectDefineProperty(OutgoingMessage.prototype,'closed',{
+__proto__: null,
+get(){
+returnthis._closed;
+},
+});
+
 ObjectDefineProperty(OutgoingMessage.prototype,'writableFinished',{
 __proto__: null,
 get(){
@@ -320,6 +337,8 @@ OutgoingMessage.prototype.destroy = function destroy(error) {
 }
 this.destroyed=true;
 
+this[kErrored]=error;
+
 if(this.socket){
 this.socket.destroy(error);
 }else{

test/parallel/test-http-client-incomingmessage-destroy.js

@@ -20,6 +20,13 @@ server.listen(0, () => {
 get({
 port: server.address().port
 },common.mustCall((res)=>{
-res.destroy(newError('Destroy test'));
+consterr=newError('Destroy test');
+assert.strictEqual(res.errored,null);
+res.destroy(err);
+assert.strictEqual(res.closed,false);
+assert.strictEqual(res.errored,err);
+res.on('close',()=>{
+assert.strictEqual(res.closed,true);
+});
 }));
 });

test/parallel/test-http-outgoing-destroyed.js

@@ -1,24 +1,55 @@
 'use strict';
 constcommon=require('../common');
 consthttp=require('http');
+constassert=require('assert');
 
-constserver=http.createServer(common.mustCall((req,res)=>{
-req.pipe(res);
-res.on('error',common.mustNotCall());
-res.on('close',common.mustCall(()=>{
-res.end('asd');
-process.nextTick(()=>{
-server.close();
-});
-}));
-})).listen(0,()=>{
-http
-.request({
-port: server.address().port,
-method: 'PUT'
-})
-.on('response',(res)=>{
-res.destroy();
-})
-.write('asd');
-});
+{
+constserver=http.createServer(common.mustCall((req,res)=>{
+assert.strictEqual(res.closed,false);
+req.pipe(res);
+res.on('error',common.mustNotCall());
+res.on('close',common.mustCall(()=>{
+assert.strictEqual(res.closed,true);
+res.end('asd');
+process.nextTick(()=>{
+server.close();
+});
+}));
+})).listen(0,()=>{
+http
+.request({
+port: server.address().port,
+method: 'PUT'
+})
+.on('response',(res)=>{
+res.destroy();
+})
+.write('asd');
+});
+}
+
+{
+constserver=http.createServer(common.mustCall((req,res)=>{
+assert.strictEqual(res.closed,false);
+req.pipe(res);
+res.on('error',common.mustNotCall());
+res.on('close',common.mustCall(()=>{
+assert.strictEqual(res.closed,true);
+process.nextTick(()=>{
+server.close();
+});
+}));
+consterr=newError('Destroy test');
+res.destroy(err);
+assert.strictEqual(res.errored,err);
+})).listen(0,()=>{
+http
+.request({
+port: server.address().port,
+method: 'PUT'
+})
+.on('error',common.mustCall())
+.write('asd');
+});
+
+}