test: cleanup test-stdout-close-catch.js

Added common.mustCall in child process on 'close' callback Changed several 'var' statements to 'const' or 'let' where appropriate Also linting PR-URL: #10006 Reviewed-By: Michael Dawson <[email protected]> Reviewed-By: Michaël Zasso <[email protected]> Reviewed-By: Colin Ihrig <[email protected]> Reviewed-By: Roman Reiss <[email protected]>

Author: furnox

test/parallel/test-stdout-close-catch.js

@@ -1,27 +1,30 @@
 'use strict';
-varcommon=require('../common');
-varassert=require('assert');
-varpath=require('path');
-varchild_process=require('child_process');
+constcommon=require('../common');
+constassert=require('assert');
+constpath=require('path');
+constchild_process=require('child_process');
 
-vartestScript=path.join(common.fixturesDir,'catch-stdout-error.js');
+consttestScript=path.join(common.fixturesDir,'catch-stdout-error.js');
 
-varcmd=JSON.stringify(process.execPath)+' '+
-JSON.stringify(testScript)+' | '+
-JSON.stringify(process.execPath)+' '+
-'-pe "process.stdin.on(\'data\' , () => process.exit(1))"';
+constcmd=JSON.stringify(process.execPath)+' '+
+JSON.stringify(testScript)+' | '+
+JSON.stringify(process.execPath)+' '+
+'-pe "process.stdin.on(\'data\' , () => process.exit(1))"';
 
-varchild=child_process.exec(cmd);
-varoutput='';
-varoutputExpect={'code': 'EPIPE',
-'errno': 'EPIPE',
-'syscall': 'write'};
+constchild=child_process.exec(cmd);
+letoutput='';
+constoutputExpect={
+code: 'EPIPE',
+errno: 'EPIPE',
+syscall: 'write'
+};
 
 child.stderr.on('data',function(c){
 output+=c;
 });
 
-child.on('close',function(code){
+
+child.on('close',common.mustCall(function(code){
 try{
 output=JSON.parse(output);
 }catch(er){
@@ -31,4 +34,4 @@ child.on('close', function(code){
 
 assert.deepStrictEqual(output,outputExpect);
 console.log('ok');
-});
+}));