test: implemented es6 conventions

implemented arrow functions and changed var to const where appropriate. PR-URL: #9669 Reviewed-By: Michaël Zasso <[email protected]> Reviewed-By: Colin Ihrig <[email protected]> Reviewed-By: James M Snell <[email protected]>

Author: ruggertech

test/parallel/test-fs-read-stream-err.js

@@ -1,43 +1,42 @@
 'use strict';
-varcommon=require('../common');
-varassert=require('assert');
-varfs=require('fs');
+constcommon=require('../common');
+constassert=require('assert');
+constfs=require('fs');
 
-varstream=fs.createReadStream(__filename,{
+conststream=fs.createReadStream(__filename,{
 bufferSize: 64
 });
-varerr=newError('BAM');
+consterr=newError('BAM');
 
-stream.on('error',common.mustCall(functionerrorHandler(err_){
-console.error('error event');
-process.nextTick(function(){
-assert.equal(stream.fd,null);
-assert.equal(err_,err);
-});
+stream.on('error',common.mustCall((err_)=>{
+process.nextTick(common.mustCall(()=>{
+assert.strictEqual(stream.fd,null);
+assert.strictEqual(err_,err);
+}));
 }));
 
-fs.close=common.mustCall(function(fd_,cb){
-assert.equal(fd_,stream.fd);
+fs.close=common.mustCall((fd_,cb)=>{
+assert.strictEqual(fd_,stream.fd);
 process.nextTick(cb);
 });
 
-varread=fs.read;
+constread=fs.read;
 fs.read=function(){
 // first time is ok.
 read.apply(fs,arguments);
 // then it breaks
-fs.read=function(){
-varcb=arguments[arguments.length-1];
-process.nextTick(function(){
+fs.read=common.mustCall(function(){
+constcb=arguments[arguments.length-1];
+process.nextTick(()=>{
 cb(err);
 });
 // and should not be called again!
-fs.read=function(){
+fs.read=()=>{
 thrownewError('BOOM!');
 };
-};
+});
 };
 
-stream.on('data',function(buf){
-stream.on('data',common.fail);// no more 'data' events should follow
+stream.on('data',(buf)=>{
+stream.on('data',()=>common.fail("no more 'data' events should follow"));
 });