test: replace function with arrow function

1. Among the list of Code and Learn, I solved the unfinished task of replacing function with arrow function: nodejs/code-and-learn#72 (comment) 2. Replace arrow function with shorter property syntax Arrow function makes `this` lexical scope. But toString expects evaluate `this` in runtime. 3. Replace this with null makeBlock does not need `this`. update `this` with `null` to clarify the intent. PR-URL: #17345 Reviewed-By: Anna Henningsen <[email protected]> Reviewed-By: Jon Moss <[email protected]> Reviewed-By: Yosuke Furukawa <[email protected]>

Author: Leko

test/parallel/test-assert.js

@@ -26,8 +26,8 @@ const a = assert;
 
 functionmakeBlock(f){
 constargs=Array.prototype.slice.call(arguments,1);
-returnfunction(){
-returnf.apply(this,args);
+return()=>{
+returnf.apply(null,args);
 };
 }
 
@@ -183,7 +183,7 @@ assert.doesNotThrow(makeBlock(a.deepEqual, a1, a2));
 
 // having an identical prototype property
 constnbRoot={
-toString: function(){return`${this.first}${this.last}`;}
+toString(){return`${this.first}${this.last}`;}
 };
 
 functionnameBuilder(first,last){
@@ -458,10 +458,10 @@ assert.throws(makeBlock(thrower, TypeError));
 'a.doesNotThrow is not catching type matching errors');
 }
 
-assert.throws(function(){assert.ifError(newError('test error'));},
+assert.throws(()=>{assert.ifError(newError('test error'));},
 /^Error:testerror$/);
-assert.doesNotThrow(function(){assert.ifError(null);});
-assert.doesNotThrow(function(){assert.ifError();});
+assert.doesNotThrow(()=>{assert.ifError(null);});
+assert.doesNotThrow(()=>{assert.ifError();});
 
 assert.throws(()=>{
 assert.doesNotThrow(makeBlock(thrower,Error),'user message');
@@ -473,7 +473,7 @@ assert.throws(() =>{
 letthrew=false;
 try{
 assert.throws(
-function(){
+()=>{
 throw({});// eslint-disable-line no-throw-literal
 },
 Array
@@ -488,7 +488,7 @@ assert.throws(() =>{
 a.throws(makeBlock(thrower,TypeError),/\[objectObject\]/);
 
 // use a fn to validate error object
-a.throws(makeBlock(thrower,TypeError),function(err){
+a.throws(makeBlock(thrower,TypeError),(err)=>{
 if((errinstanceofTypeError)&&/\[objectObject\]/.test(err)){
 returntrue;
 }
@@ -591,7 +591,7 @@ testAssertionMessage({a: NaN, b: Infinity, c: -Infinity },
 letthrew=false;
 try{
 // eslint-disable-next-line no-restricted-syntax
-assert.throws(function(){
+assert.throws(()=>{
 assert.ifError(null);
 });
 }catch(e){

test/parallel/test-domain-top-level-error-handler-clears-stack.js

@@ -9,8 +9,8 @@ const domain = require('domain');
  */
 constd=domain.create();
 
-d.on('error',common.mustCall(function(){
-process.nextTick(function(){
+d.on('error',common.mustCall(()=>{
+process.nextTick(()=>{
 // Scheduling a callback with process.nextTick will enter a _new_ domain,
 // and the callback will be called after the domain that handled the error
 // was exited. So there should be only one domain on the domains stack if
@@ -29,6 +29,6 @@ d.on('error', common.mustCall(function(){
 });
 }));
 
-d.run(function(){
+d.run(()=>{
 thrownewError('Error from domain');
 });

test/parallel/test-querystring.js

@@ -129,7 +129,7 @@ const qsWeirdObjects = [
 [{regexp: /./g},'regexp=',{'regexp': ''}],
 // eslint-disable-next-line no-unescaped-regexp-dot
 [{regexp: newRegExp('.','g')},'regexp=',{'regexp': ''}],
-[{fn: function(){}},'fn=',{'fn': ''}],
+[{fn: ()=>{}},'fn=',{'fn': ''}],
 [{fn: newFunction('')},'fn=',{'fn': ''}],
 [{math: Math},'math=',{'math': ''}],
 [{e: extendedFunction},'e=',{'e': ''}],
@@ -189,7 +189,7 @@ function check(actual, expected, input){
 `Expected keys: ${inspect(expectedKeys)}`;
 }
 assert.deepStrictEqual(actualKeys,expectedKeys,msg);
-expectedKeys.forEach(function(key){
+expectedKeys.forEach((key)=>{
 if(typeofinput==='string'){
 msg=`Input: ${inspect(input)}\n`+
 `Key: ${inspect(key)}\n`+
@@ -203,21 +203,21 @@ function check(actual, expected, input){
 }
 
 // test that the canonical qs is parsed properly.
-qsTestCases.forEach(function(testCase){
+qsTestCases.forEach((testCase)=>{
 check(qs.parse(testCase[0]),testCase[2],testCase[0]);
 });
 
 // test that the colon test cases can do the same
-qsColonTestCases.forEach(function(testCase){
+qsColonTestCases.forEach((testCase)=>{
 check(qs.parse(testCase[0],'',':'),testCase[2],testCase[0]);
 });
 
 // test the weird objects, that they get parsed properly
-qsWeirdObjects.forEach(function(testCase){
+qsWeirdObjects.forEach((testCase)=>{
 check(qs.parse(testCase[1]),testCase[2],testCase[1]);
 });
 
-qsNoMungeTestCases.forEach(function(testCase){
+qsNoMungeTestCases.forEach((testCase)=>{
 assert.deepStrictEqual(testCase[0],qs.stringify(testCase[1],'&','='));
 });
 
@@ -255,15 +255,15 @@ qsNoMungeTestCases.forEach(function(testCase){
 // now test stringifying
 
 // basic
-qsTestCases.forEach(function(testCase){
+qsTestCases.forEach((testCase)=>{
 assert.strictEqual(testCase[1],qs.stringify(testCase[2]));
 });
 
-qsColonTestCases.forEach(function(testCase){
+qsColonTestCases.forEach((testCase)=>{
 assert.strictEqual(testCase[1],qs.stringify(testCase[2],'',':'));
 });
 
-qsWeirdObjects.forEach(function(testCase){
+qsWeirdObjects.forEach((testCase)=>{
 assert.strictEqual(testCase[1],qs.stringify(testCase[0]));
 });
 
@@ -292,7 +292,7 @@ assert.strictEqual('foo=', qs.stringify({foo: Infinity }));
 assert.strictEqual(f,'a=b&q=x%3Dy%26y%3Dz');
 }
 
-assert.doesNotThrow(function(){
+assert.doesNotThrow(()=>{
 qs.parse(undefined);
 });
 
@@ -423,15 +423,15 @@ check(qs.parse('%\u0100=%\u0101'),{'%Ā': '%ā'});
 }
 
 // Test QueryString.unescapeBuffer
-qsUnescapeTestCases.forEach(function(testCase){
+qsUnescapeTestCases.forEach((testCase)=>{
 assert.strictEqual(qs.unescape(testCase[0]),testCase[1]);
 assert.strictEqual(qs.unescapeBuffer(testCase[0]).toString(),testCase[1]);
 });
 
 // test overriding .unescape
 {
 constprevUnescape=qs.unescape;
-qs.unescape=function(str){
+qs.unescape=(str)=>{
 returnstr.replace(/o/g,'_');
 };
 check(

test/parallel/test-writeint.js

@@ -37,10 +37,10 @@ function test8(clazz){
 assert.strictEqual(0xfb,buffer[1]);
 
 /* Make sure we handle truncation correctly */
-assert.throws(function(){
+assert.throws(()=>{
 buffer.writeInt8(0xabc,0);
 },errorOutOfBounds);
-assert.throws(function(){
+assert.throws(()=>{
 buffer.writeInt8(0xabc,0);
 },errorOutOfBounds);
 
@@ -50,10 +50,10 @@ function test8(clazz){
 
 assert.strictEqual(0x7f,buffer[0]);
 assert.strictEqual(0x80,buffer[1]);
-assert.throws(function(){
+assert.throws(()=>{
 buffer.writeInt8(0x7f+1,0);
 },errorOutOfBounds);
-assert.throws(function(){
+assert.throws(()=>{
 buffer.writeInt8(-0x80-1,0);
 },errorOutOfBounds);
 }
@@ -90,10 +90,10 @@ function test16(clazz){
 assert.strictEqual(0xff,buffer[1]);
 assert.strictEqual(0x80,buffer[2]);
 assert.strictEqual(0x00,buffer[3]);
-assert.throws(function(){
+assert.throws(()=>{
 buffer.writeInt16BE(0x7fff+1,0);
 },errorOutOfBounds);
-assert.throws(function(){
+assert.throws(()=>{
 buffer.writeInt16BE(-0x8000-1,0);
 },errorOutOfBounds);
 
@@ -103,10 +103,10 @@ function test16(clazz){
 assert.strictEqual(0x7f,buffer[1]);
 assert.strictEqual(0x00,buffer[2]);
 assert.strictEqual(0x80,buffer[3]);
-assert.throws(function(){
+assert.throws(()=>{
 buffer.writeInt16LE(0x7fff+1,0);
 },errorOutOfBounds);
-assert.throws(function(){
+assert.throws(()=>{
 buffer.writeInt16LE(-0x8000-1,0);
 },errorOutOfBounds);
 }
@@ -159,10 +159,10 @@ function test32(clazz){
 assert.strictEqual(0x00,buffer[5]);
 assert.strictEqual(0x00,buffer[6]);
 assert.strictEqual(0x00,buffer[7]);
-assert.throws(function(){
+assert.throws(()=>{
 buffer.writeInt32BE(0x7fffffff+1,0);
 },errorOutOfBounds);
-assert.throws(function(){
+assert.throws(()=>{
 buffer.writeInt32BE(-0x80000000-1,0);
 },errorOutOfBounds);
 
@@ -176,10 +176,10 @@ function test32(clazz){
 assert.strictEqual(0x00,buffer[5]);
 assert.strictEqual(0x00,buffer[6]);
 assert.strictEqual(0x80,buffer[7]);
-assert.throws(function(){
+assert.throws(()=>{
 buffer.writeInt32LE(0x7fffffff+1,0);
 },errorOutOfBounds);
-assert.throws(function(){
+assert.throws(()=>{
 buffer.writeInt32LE(-0x80000000-1,0);
 },errorOutOfBounds);
 }

test/parallel/test-zerolengthbufferbug.js

@@ -4,20 +4,20 @@
 constcommon=require('../common');
 consthttp=require('http');
 
-constserver=http.createServer(function(req,res){
+constserver=http.createServer((req,res)=>{
 constbuffer=Buffer.alloc(0);
 // FIXME: WTF gjslint want this?
 res.writeHead(200,{'Content-Type': 'text/html',
 'Content-Length': buffer.length});
 res.end(buffer);
 });
 
-server.listen(0,common.mustCall(function(){
-http.get({port: this.address().port},common.mustCall(function(res){
+server.listen(0,common.mustCall(()=>{
+http.get({port: server.address().port},common.mustCall((res)=>{
 
 res.on('data',common.mustNotCall());
 
-res.on('end',function(d){
+res.on('end',(d)=>{
 server.close();
 });
 }));