child_process: fire close event from stdio

PR-URL: #22892
Reviewed-By: Anna Henningsen <anna@addaleax.net>

Author: koh110

lib/internal/child_process.js

@@ -386,6 +386,9 @@ ChildProcess.prototype.spawn = function(options) {
 // The stream is already cloned and piped, thus close it.
 if(stream.type==='wrap'){
 stream.handle.close();
+if(stream._stdio&&stream._stdioinstanceofEventEmitter){
+stream._stdio.emit('close');
+}
 continue;
 }
 
@@ -946,7 +949,8 @@ function _validateStdio(stdio, sync) {
 acc.push({
 type: 'wrap',
 wrapType: getHandleWrapType(handle),
-handle: handle
+handle: handle,
+_stdio: stdio
 });
 }elseif(isArrayBufferView(stdio)||typeofstdio==='string'){
 if(!sync){

test/parallel/test-child-process-server-close.js

@@ -0,0 +1,20 @@
+'use strict';
+
+constcommon=require('../common');
+const{ spawn }=require('child_process');
+constnet=require('net');
+
+constserver=net.createServer((conn)=>{
+conn.on('close',common.mustCall());
+
+spawn(process.execPath,['-v'],{
+stdio: ['ignore',conn,'ignore']
+}).on('close',common.mustCall());
+}).listen(common.PIPE,()=>{
+constclient=net.connect(common.PIPE,common.mustCall());
+client.on('data',()=>{
+client.end(()=>{
+server.close();
+});
+});
+});