From 08b93ff3c363d22cfac38e6a16795e2022800e8d Mon Sep 17 00:00:00 2001
From: Andy Hanson <anhans@microsoft.com>
Date: Tue, 21 Feb 2017 15:01:48 -0800
Subject: [PATCH] WIP

---
 d3-array/d3-array-tests.ts                    |  83 +++++-----
 .../v3/react-router-redux-tests.ts            |   2 +-
 react-router/react-router-tests.tsx           |  12 +-
 swiper/v2/swiper-tests.ts                     |  38 ++---
 vinyl-fs/vinyl-fs-tests.ts                    | 155 +++++++++---------
 5 files changed, 141 insertions(+), 149 deletions(-)

diff --git a/d3-array/d3-array-tests.ts b/d3-array/d3-array-tests.ts
index e086fd2502..74b749bea3 100644
--- a/d3-array/d3-array-tests.ts
+++ b/d3-array/d3-array-tests.ts
@@ -15,22 +15,22 @@ import { timeYear } from 'd3-time';
 // -----------------------------------------------------------------------------
 
 class NumCoercible {
-    public a: number;
+    a: number;
 
     constructor(a: number) {
         this.a = a;
     }
-    public valueOf() {
+    valueOf() {
         return this.a;
     }
 }
 
 class MixedObject {
 
-    public num: number;
-    public str: string;
-    public numeric: NumCoercible;
-    public date: Date;
+    num: number;
+    str: string;
+    numeric: NumCoercible;
+    date: Date;
 
     constructor(a: number, date: Date) {
         this.num = a;
@@ -55,32 +55,32 @@ let mixedOrUndefinedExtent: [d3Array.Primitive | NumCoercible, d3Array.Primitive
 let dateOrUndefinedExtent: [Date, Date] | [undefined, undefined];
 
 let numbersArray = [10, 20, 30, 40, 50];
-let numbersOrUndefinedArray = [10, 20, undefined, null, 40, 50];
-let stringyNumbersArray = ['10', '20', '30', '40', '50'];
-let numericArray = [new NumCoercible(10), new NumCoercible(20), new NumCoercible(30), new NumCoercible(40), new NumCoercible(50)];
-let dateArray = [new Date(2016, 6, 1), new Date(2016, 7, 30), new Date(2015, 3, 15)];
-let mixedObjectArray = [
+const numbersOrUndefinedArray = [10, 20, undefined, null, 40, 50];
+const stringyNumbersArray = ['10', '20', '30', '40', '50'];
+const numericArray = [new NumCoercible(10), new NumCoercible(20), new NumCoercible(30), new NumCoercible(40), new NumCoercible(50)];
+const dateArray = [new Date(2016, 6, 1), new Date(2016, 7, 30), new Date(2015, 3, 15)];
+const mixedObjectArray = [
     new MixedObject(10, new Date(2016, 6, 1)),
     new MixedObject(20, new Date(2016, 7, 30)),
     new MixedObject(30, new Date(2015, 3, 15)),
     new MixedObject(40, new Date(2014, 3, 15)),
     new MixedObject(50, new Date(2017, 4, 15))
 ];
-let mixedObjectOrUndefinedArray = [...mixedObjectArray, undefined]
+const mixedObjectOrUndefinedArray = [...mixedObjectArray, undefined];
 
-function accessorMixedObjectToNum(datum: MixedObject, index: number, array: Array<MixedObject>): number {
+function accessorMixedObjectToNum(datum: MixedObject, index: number, array: MixedObject[]): number {
     return datum.num;
 }
 
-function accessorMixedObjectToStr(datum: MixedObject, index: number, array: Array<MixedObject>): string {
+function accessorMixedObjectToStr(datum: MixedObject, index: number, array: MixedObject[]): string {
     return datum.str;
 }
 
-function accessorMixedObjectToNumeric(datum: MixedObject, index: number, array: Array<MixedObject>): NumCoercible {
+function accessorMixedObjectToNumeric(datum: MixedObject, index: number, array: MixedObject[]): NumCoercible {
     return datum.numeric;
 }
 
-function accessorMixedObjectToDate(datum: MixedObject, index: number, array: Array<MixedObject>): Date {
+function accessorMixedObjectToDate(datum: MixedObject, index: number, array: MixedObject[]): Date {
     return datum.date;
 }
 
@@ -88,7 +88,7 @@ function accessorMixedObjectToNumOrUndefined(datum: MixedObject | undefined, ind
     return datum ? datum.num : undefined;
 }
 
-function accessorMixedObjectToStrOrUndefined(datum: MixedObject | undefined, index: number, array: Array<MixedObject>): string | undefined | null {
+function accessorMixedObjectToStrOrUndefined(datum: MixedObject | undefined, index: number, array: MixedObject[]): string | undefined | null {
     return datum ? datum.str : undefined;
 }
 
@@ -210,17 +210,17 @@ numOrUndefined = d3Array.variance(mixedObjectOrUndefinedArray, accessorMixedObje
 
 // scan() ----------------------------------------------------------------------
 
-numOrUndefined = d3Array.scan(numbersArray)
+numOrUndefined = d3Array.scan(numbersArray);
 
-numOrUndefined = d3Array.scan(mixedObjectArray, function (a, b) {
-    let aElem: MixedObject = a;
-    let bElem: MixedObject = b;
+numOrUndefined = d3Array.scan(mixedObjectArray, (a, b) => {
+    const aElem: MixedObject = a;
+    const bElem: MixedObject = b;
     return a.num - b.num;
 });
 
-numOrUndefined = d3Array.scan(mixedObjectOrUndefinedArray, function (a, b) {
-    let aElem: MixedObject | undefined = a;
-    let bElem: MixedObject | undefined = b;
+numOrUndefined = d3Array.scan(mixedObjectOrUndefinedArray, (a, b) => {
+    const aElem: MixedObject | undefined = a;
+    const bElem: MixedObject | undefined = b;
     return a && b ? a.num - b.num : NaN;
 });
 
@@ -268,19 +268,16 @@ num = d3Array.bisect([new Date(2010, 1, 1), new Date(2011, 1, 1), new Date(2012,
 
 // bisector() ------------------------------------------------------------------
 
-mixedObjectArray.sort(function (a, b) { return a.date.valueOf() - b.date.valueOf(); });
+mixedObjectArray.sort((a, b) => a.date.valueOf() - b.date.valueOf());
 
 let mixedObjectDateBisectorObject: d3Array.Bisector<MixedObject, Date>;
 
 // define using accessor
-mixedObjectDateBisectorObject = d3Array.bisector<MixedObject, Date>(function (el) {
-    return el.date;
-});
+mixedObjectDateBisectorObject = d3Array.bisector<MixedObject, Date>(el => el.date);
 
 // define using comparator
-mixedObjectDateBisectorObject = d3Array.bisector<MixedObject, Date>(function (el, x) {
-    return el.date.valueOf() - x.valueOf();
-});
+mixedObjectDateBisectorObject = d3Array.bisector<MixedObject, Date>((el, x) =>
+    el.date.valueOf() - x.valueOf());
 
 // bisect left
 num = mixedObjectDateBisectorObject.left(mixedObjectArray, new Date(2015, 3, 14));
@@ -346,14 +343,14 @@ mergedArray = d3Array.permute(mergedArray, [1, 0, 2, 5, 3, 4, 6]);
 
 // Getting an ordered array with object properties
 
-let testObject = {
+const testObject = {
     val: 10,
     name: 'Test',
     when: new Date(),
     more: [10, 30, 40]
 };
 
-let x: Array<number | string | Date | number[]> = d3Array.permute(testObject, ['name', 'val', 'when', 'more']);
+const x: Array<number | string | Date | number[]> = d3Array.permute(testObject, ['name', 'val', 'when', 'more']);
 
 
 // range() ---------------------------------------------------------------------
@@ -412,7 +409,7 @@ testArrays = d3Array.zip(
 // Test Histogram
 // -----------------------------------------------------------------------------
 
-let tScale = scaleTime();
+const tScale = scaleTime();
 
 // Create histogram generator ==================================================
 
@@ -426,10 +423,10 @@ testHistogram = d3Array.histogram<MixedObject, Date>();
 
 // value(...) ------------------------------------------------------------------
 
-testHistogram = testHistogram.value(function (d, i, data) {
-    let datum: MixedObject = d; // d is of type MixedObject
-    let index: number = i; // i is number
-    let array: MixedObject[] = data; // data is of type MixedObject[]
+testHistogram = testHistogram.value((d, i, data) => {
+    const datum: MixedObject = d; // d is of type MixedObject
+    const index: number = i; // i is number
+    const array: MixedObject[] = data; // data is of type MixedObject[]
     return datum.date;
 });
 
@@ -442,16 +439,14 @@ valueAccessorFn = testHistogram.value();
 testHistogram = testHistogram.domain([new Date(2014, 3, 15), new Date(2017, 4, 15)]);
 
 // usage with scale domain:
-let domain = tScale.domain();
+const domain = tScale.domain();
 
 testHistogram = testHistogram.domain([domain[0], domain[domain.length]]);
 
 // testHistogram = testHistogram.domain(tScale.domain()); // fails, as scale domain is an array with possibly more than the two elements expected by histogram
 
 // use with accessor function
-testHistogram = testHistogram.domain(function (values) {
-    return [values[0], values[values.length]];
-});
+testHistogram = testHistogram.domain(values => [values[0], values[values.length]]);
 
 // get current domain accessor function
 let domainAccessorFn: (values: Date[]) => [Date, Date];
@@ -470,7 +465,7 @@ defaultHistogram = defaultHistogram.thresholds(d3Array.thresholdScott);
 testHistogram = testHistogram.thresholds([new Date(2015, 11, 15), new Date(2016, 6, 1), new Date(2016, 8, 30)]);
 
 // with thresholds value array accessors
-testHistogram = testHistogram.thresholds(function (values: Date[], min: Date, max: Date) {
+testHistogram = testHistogram.thresholds((values: Date[], min: Date, max: Date) => {
     let thresholds: Date[];
     thresholds = [values[0], values[2], values[4]];
     return thresholds;
@@ -498,7 +493,7 @@ let testBin: d3Array.Bin<MixedObject, Date>;
 testBin = testBins[0];
 
 num = testBin.length; // defaultBin is array
-let mixedObject: MixedObject = testBin[0]; // with element type MixedObject
+const mixedObject: MixedObject = testBin[0]; // with element type MixedObject
 date = testBin.x0; // bin lower bound is Date
 date = testBin.x1; // bin upper bound is Date
 
diff --git a/react-router-redux/v3/react-router-redux-tests.ts b/react-router-redux/v3/react-router-redux-tests.ts
index d98ac08768..9d7beca92b 100644
--- a/react-router-redux/v3/react-router-redux-tests.ts
+++ b/react-router-redux/v3/react-router-redux-tests.ts
@@ -5,7 +5,7 @@ import { syncHistory, routeReducer } from 'react-router-redux';
 const reducer = combineReducers({ routing: routeReducer });
 
 // Sync dispatched route actions to the history
-const browserHistory = createHistory()
+const browserHistory = createHistory();
 const reduxRouterMiddleware = syncHistory(browserHistory);
 const createStoreWithMiddleware = applyMiddleware(reduxRouterMiddleware)(createStore);
 
diff --git a/react-router/react-router-tests.tsx b/react-router/react-router-tests.tsx
index 9e7bcb4efc..85db539951 100644
--- a/react-router/react-router-tests.tsx
+++ b/react-router/react-router-tests.tsx
@@ -24,21 +24,21 @@ import {
 } from "react-router";
 import { createHistory, History } from "history";
 
-const routerHistory = useRouterHistory(createHistory)({ basename: "/test" })
+const routerHistory = useRouterHistory(createHistory)({ basename: "/test" });
 
 interface CustomHistory {
 	test(): undefined;
 }
 
-type CombinedHistory = History & CustomHistory
+type CombinedHistory = History & CustomHistory;
 
 function createCustomHistory(history: History): CombinedHistory {
 	return {
 		...history,
 		test() {}
-	} as CombinedHistory
+	} as CombinedHistory;
 }
-const customHistory = createCustomHistory(browserHistory)
+const customHistory = createCustomHistory(browserHistory);
 
 
 const NavLink = (props: LinkProps) => (
@@ -141,13 +141,13 @@ ReactDOM.render((
 	<Router history={ routerHistory }>
 		<Route path="/" component={Master} />
 	</Router>
-), document.body)
+), document.body);
 
 ReactDOM.render((
 	<Router history={ customHistory }>
 		<Route path="/" component={Master} />
 	</Router>
-), document.body)
+), document.body);
 
 
 const history = createMemoryHistory("baseurl");
diff --git a/swiper/v2/swiper-tests.ts b/swiper/v2/swiper-tests.ts
index 12abcc8944..ad1180a352 100644
--- a/swiper/v2/swiper-tests.ts
+++ b/swiper/v2/swiper-tests.ts
@@ -14,12 +14,12 @@ function defaultDemo() {
         paginationClickable: true
     });
 
-    $('.arrow-left').on('click', function (e) {
+    $('.arrow-left').on('click', e => {
         e.preventDefault();
         mySwiper.swipePrev();
     });
 
-    $('.arrow-right').on('click', function (e) {
+    $('.arrow-right').on('click', e => {
         e.preventDefault();
         mySwiper.swipeNext();
     });
@@ -40,7 +40,7 @@ function dynamicSlides() {
         pagination: '.pagination',
         paginationClickable: true
     });
-    
+
     function randomColor() {
         var colors = ('blue red green orange pink').split(' ');
         return colors[Math.floor(Math.random() * colors.length)];
@@ -48,41 +48,41 @@ function dynamicSlides() {
 
     var count = 4;
 
-    $('.sdl-append').click(function (e) {
+    $('.sdl-append').click(e => {
         e.preventDefault();
-        mySwiper.appendSlide('<div class="title">Slide ' + (++count) + '</div>', 'swiper-slide ' + randomColor() + '-slide')
+        mySwiper.appendSlide('<div class="title">Slide ' + (++count) + '</div>', 'swiper-slide ' + randomColor() + '-slide');
     });
 
-    $('.sdl-prepend').click(function (e) {
+    $('.sdl-prepend').click(e => {
         e.preventDefault();
-        mySwiper.prependSlide('<div class="title">Slide  ' + (++count) + '</div>', 'swiper-slide ' + randomColor() + '-slide')
+        mySwiper.prependSlide('<div class="title">Slide  ' + (++count) + '</div>', 'swiper-slide ' + randomColor() + '-slide');
     });
 
-    $('.sdl-swap').click(function (e) {
+    $('.sdl-swap').click(e => {
         e.preventDefault();
         mySwiper
             .getFirstSlide()
             .insertAfter(1);
     });
 
-    $('.sdl-insert').click(function (e) {
+    $('.sdl-insert').click(e => {
         e.preventDefault();
         mySwiper
             .createSlide('<div class="title">Slide  ' + (++count) + '</div>', 'swiper-slide ' + randomColor() + '-slide')
             .insertAfter(0);
     });
 
-    $('.sdl-remove1').click(function (e) {
+    $('.sdl-remove1').click(e => {
         e.preventDefault();
         mySwiper.removeSlide(0);
     });
 
-    $('.sdl-removel').click(function (e) {
+    $('.sdl-removel').click(e => {
         e.preventDefault();
         mySwiper.removeLastSlide();
     });
 
-    $('.sdl-remove2').click(function (e) {
+    $('.sdl-remove2').click(e => {
         e.preventDefault();
         mySwiper.removeSlide(1);
     });
@@ -108,7 +108,7 @@ function freeMode() {
     });
 }
 
-// 06-carousel-mode.html 
+// 06-carousel-mode.html
 function carouselMode() {
     var mySwiper = new Swiper('.swiper-container', {
         pagination: '.pagination',
@@ -174,14 +174,14 @@ function tabs() {
         speed: 500
     });
 
-    $(".tabs a").on('touchstart mousedown', function (e) {
+    $(".tabs a").on('touchstart mousedown', e => {
         e.preventDefault();
         $(".tabs .active").removeClass('active');
         $(this).addClass('active');
         tabsSwiper.swipeTo($(this).index());
     });
 
-    $(".tabs a").click(function (e) {
+    $(".tabs a").click(e => {
         e.preventDefault();
     });
 }
@@ -190,20 +190,20 @@ function tabs() {
 function tabsFeedback() {
     var tabsSwiper = new Swiper('.swiper-container', {
         speed: 500,
-        onSlideChangeStart: function () {
+        onSlideChangeStart: () => {
             $(".tabs .active").removeClass('active');
             $(".tabs a").eq(tabsSwiper.activeIndex).addClass('active');
         }
     });
 
-    $(".tabs a").on('touchstart mousedown', function (e) {
+    $(".tabs a").on('touchstart mousedown', e => {
         e.preventDefault();
         $(".tabs .active").removeClass('active');
         $(this).addClass('active');
         tabsSwiper.swipeTo($(this).index());
     });
 
-    $(".tabs a").click(function (e) {
+    $(".tabs a").click(e => {
         e.preventDefault();
     });
 }
@@ -256,7 +256,7 @@ function visibilityApi() {
     });
 }
 
-// 17 - responsive.html 
+// 17 - responsive.html
 function responsive() {
     var mySwiper = new Swiper('.swiper-container', {
         pagination: '.pagination',
diff --git a/vinyl-fs/vinyl-fs-tests.ts b/vinyl-fs/vinyl-fs-tests.ts
index 41dfa92c4c..33d031f521 100644
--- a/vinyl-fs/vinyl-fs-tests.ts
+++ b/vinyl-fs/vinyl-fs-tests.ts
@@ -1,6 +1,3 @@
-/// <reference types="mocha" />
-/// <reference types="should" />
-
 // from src
 
 import * as vfs from 'vinyl-fs';
@@ -22,16 +19,16 @@ import 'mocha';
 declare var gulp: any;
 declare var bufferStream: any;
 
-var dataWrap = function (fn: any) {
-   return function (data: any, enc: any, cb: any) {
+var dataWrap = (fn: any) => {
+   return (data: any, enc: any, cb: any) => {
       fn(data);
       cb();
    };
 };
 
-describe('source stream', function () {
+describe('source stream', () => {
 
-   it('should explode on invalid glob (empty)', function (done) {
+   it('should explode on invalid glob (empty)', done => {
       var stream: any;
       try {
          stream = gulp.src();
@@ -42,7 +39,7 @@ describe('source stream', function () {
       }
    });
 
-   it('should explode on invalid glob (number)', function (done) {
+   it('should explode on invalid glob (number)', done => {
       var stream: any;
       try {
          stream = gulp.src(123);
@@ -53,7 +50,7 @@ describe('source stream', function () {
       }
    });
 
-   it('should explode on invalid glob (empty array)', function (done) {
+   it('should explode on invalid glob (empty array)', done => {
       var stream: any;
       try {
          stream = gulp.src([]);
@@ -64,7 +61,7 @@ describe('source stream', function () {
       }
    });
 
-   it('should pass through writes', function (done) {
+   it('should pass through writes', done => {
       var expectedPath = path.join(__dirname, "./fixtures/test.coffee");
       var expectedContent = fs.readFileSync(expectedPath);
 
@@ -75,7 +72,7 @@ describe('source stream', function () {
          contents: expectedContent
       });
 
-      var onEnd = function () {
+      var onEnd = () => {
          buffered.length.should.equal(1);
          buffered[0].should.equal(expectedFile);
          bufEqual(buffered[0].contents, expectedContent).should.equal(true);
@@ -91,11 +88,11 @@ describe('source stream', function () {
       stream.end();
    });
 
-   it('should glob a file with default settings', function (done) {
+   it('should glob a file with default settings', done => {
       var expectedPath = path.join(__dirname, "./fixtures/test.coffee");
       var expectedContent = fs.readFileSync(expectedPath);
 
-      var onEnd = function () {
+      var onEnd = () => {
          buffered.length.should.equal(1);
          should.exist(buffered[0].stat);
          buffered[0].path.should.equal(expectedPath);
@@ -111,11 +108,11 @@ describe('source stream', function () {
       stream.pipe(bufferStream);
    });
 
-   it('should glob a file with default settings and relative cwd', function (done) {
+   it('should glob a file with default settings and relative cwd', done => {
       var expectedPath = path.join(__dirname, "./fixtures/test.coffee");
       var expectedContent = fs.readFileSync(expectedPath);
 
-      var onEnd = function () {
+      var onEnd = () => {
          buffered.length.should.equal(1);
          should.exist(buffered[0].stat);
          buffered[0].path.should.equal(expectedPath);
@@ -131,10 +128,10 @@ describe('source stream', function () {
       stream.pipe(bufferStream);
    });
 
-   it('should glob a directory with default settings', function (done) {
+   it('should glob a directory with default settings', done => {
       var expectedPath = path.join(__dirname, "./fixtures/wow");
 
-      var onEnd = function () {
+      var onEnd = () => {
          buffered.length.should.equal(1);
          buffered[0].path.should.equal(expectedPath);
          buffered[0].isNull().should.equal(true);
@@ -149,11 +146,11 @@ describe('source stream', function () {
       stream.pipe(bufferStream);
    });
 
-   it('should glob a file with with no contents', function (done) {
+   it('should glob a file with with no contents', done => {
       var expectedPath = path.join(__dirname, "./fixtures/test.coffee");
       var expectedContent = fs.readFileSync(expectedPath);
 
-      var onEnd = function () {
+      var onEnd = () => {
          buffered.length.should.equal(1);
          buffered[0].path.should.equal(expectedPath);
          buffered[0].isNull().should.equal(true);
@@ -168,22 +165,22 @@ describe('source stream', function () {
       stream.pipe(bufferStream);
    });
 
-   it('should glob a file with streaming contents', function (done) {
+   it('should glob a file with streaming contents', done => {
       var expectedPath = path.join(__dirname, "./fixtures/test.coffee");
       var expectedContent = fs.readFileSync(expectedPath);
 
-      var onEnd = function () {
+      var onEnd = () => {
          buffered.length.should.equal(1);
          should.exist(buffered[0].stat);
          buffered[0].path.should.equal(expectedPath);
          buffered[0].isStream().should.equal(true);
 
          var contentBuffer = new Buffer([]);
-         var contentBufferStream = through(dataWrap(function (data: any) {
+         var contentBufferStream = through(dataWrap((data: any) => {
             contentBuffer = Buffer.concat([contentBuffer, data]);
          }));
          buffered[0].contents.pipe(contentBufferStream);
-         buffered[0].contents.once('end', function () {
+         buffered[0].contents.once('end', () => {
             bufEqual(contentBuffer, expectedContent);
             done();
          });
@@ -212,26 +209,26 @@ import rimraf = require('rimraf');
 // var should = require('should');
 // require('mocha');
 
-var wipeOut = function (cb: any) {
+var wipeOut = (cb: any) => {
    rimraf(path.join(__dirname, "./out-fixtures/"), cb);
 };
 
-var dataWrap = function (fn: any) {
-   return function (data: any, enc: any, cb: any) {
+var dataWrap = (fn: any) => {
+   return (data: any, enc: any, cb: any) => {
       fn(data);
       cb();
    };
 };
 
-var realMode = function (n: any) {
+var realMode = (n: any) => {
    return n & parseInt("07777", 8);
 };
 
-describe('dest stream', function () {
+describe('dest stream', () => {
    beforeEach(wipeOut);
    afterEach(wipeOut);
 
-   it('should explode on invalid folder', function (done) {
+   it('should explode on invalid folder', done => {
       var stream: any;
       try {
          stream = gulp.dest();
@@ -242,7 +239,7 @@ describe('dest stream', function () {
       }
    });
 
-   it('should pass through writes with cwd', function (done) {
+   it('should pass through writes with cwd', done => {
       var inputPath = path.join(__dirname, "./fixtures/test.coffee");
 
       var expectedFile = new File({
@@ -252,7 +249,7 @@ describe('dest stream', function () {
          contents: null
       });
 
-      var onEnd = function () {
+      var onEnd = () => {
          buffered.length.should.equal(1);
          buffered[0].should.equal(expectedFile);
          done();
@@ -267,7 +264,7 @@ describe('dest stream', function () {
       stream.end();
    });
 
-   it('should pass through writes with default cwd', function (done) {
+   it('should pass through writes with default cwd', done => {
       var inputPath = path.join(__dirname, "./fixtures/test.coffee");
 
       var expectedFile = new File({
@@ -277,7 +274,7 @@ describe('dest stream', function () {
          contents: null
       });
 
-      var onEnd = function () {
+      var onEnd = () => {
          buffered.length.should.equal(1);
          buffered[0].should.equal(expectedFile);
          done();
@@ -292,7 +289,7 @@ describe('dest stream', function () {
       stream.end();
    });
 
-   it('should not write null files', function (done) {
+   it('should not write null files', done => {
       var inputPath = path.join(__dirname, "./fixtures/test.coffee");
       var inputBase = path.join(__dirname, "./fixtures/");
       var expectedPath = path.join(__dirname, "./out-fixtures/test.coffee");
@@ -306,7 +303,7 @@ describe('dest stream', function () {
          contents: null
       });
 
-      var onEnd = function () {
+      var onEnd = () => {
          buffered.length.should.equal(1);
          buffered[0].should.equal(expectedFile);
          buffered[0].cwd.should.equal(expectedCwd, 'cwd should have changed');
@@ -325,7 +322,7 @@ describe('dest stream', function () {
       stream.end();
    });
 
-   it('should write buffer files to the right folder with relative cwd', function (done) {
+   it('should write buffer files to the right folder with relative cwd', done => {
       var inputPath = path.join(__dirname, "./fixtures/test.coffee");
       var inputBase = path.join(__dirname, "./fixtures/");
       var expectedPath = path.join(__dirname, "./out-fixtures/test.coffee");
@@ -340,7 +337,7 @@ describe('dest stream', function () {
          contents: expectedContents
       });
 
-      var onEnd = function () {
+      var onEnd = () => {
          buffered.length.should.equal(1);
          buffered[0].should.equal(expectedFile);
          buffered[0].cwd.should.equal(expectedCwd, 'cwd should have changed');
@@ -360,7 +357,7 @@ describe('dest stream', function () {
       stream.end();
    });
 
-   it('should write buffer files to the right folder', function (done) {
+   it('should write buffer files to the right folder', done => {
       var inputPath = path.join(__dirname, "./fixtures/test.coffee");
       var inputBase = path.join(__dirname, "./fixtures/");
       var expectedPath = path.join(__dirname, "./out-fixtures/test.coffee");
@@ -379,7 +376,7 @@ describe('dest stream', function () {
          }
       });
 
-      var onEnd = function () {
+      var onEnd = () => {
          buffered.length.should.equal(1);
          buffered[0].should.equal(expectedFile);
          buffered[0].cwd.should.equal(expectedCwd, 'cwd should have changed');
@@ -400,7 +397,7 @@ describe('dest stream', function () {
       stream.end();
    });
 
-   it('should write streaming files to the right folder', function (done) {
+   it('should write streaming files to the right folder', done => {
       var inputPath = path.join(__dirname, "./fixtures/test.coffee");
       var inputBase = path.join(__dirname, "./fixtures/");
       var expectedPath = path.join(__dirname, "./out-fixtures/test.coffee");
@@ -420,7 +417,7 @@ describe('dest stream', function () {
          }
       });
 
-      var onEnd = function () {
+      var onEnd = () => {
          buffered.length.should.equal(1);
          buffered[0].should.equal(expectedFile);
          buffered[0].cwd.should.equal(expectedCwd, 'cwd should have changed');
@@ -438,14 +435,14 @@ describe('dest stream', function () {
       bufferStream = through.obj(dataWrap(buffered.push.bind(buffered)), onEnd);
       stream.pipe(bufferStream);
       stream.write(expectedFile);
-      setTimeout(function () {
+      setTimeout(() => {
          contentStream.write(expectedContents);
          contentStream.end();
       }, 100);
       stream.end();
    });
 
-   it('should write directories to the right folder', function (done) {
+   it('should write directories to the right folder', done => {
       var inputPath = path.join(__dirname, "./fixtures/test");
       var inputBase = path.join(__dirname, "./fixtures/");
       var expectedPath = path.join(__dirname, "./out-fixtures/test");
@@ -464,7 +461,7 @@ describe('dest stream', function () {
          }
       });
 
-      var onEnd = function () {
+      var onEnd = () => {
          buffered.length.should.equal(1);
          buffered[0].should.equal(expectedFile);
          buffered[0].cwd.should.equal(expectedCwd, 'cwd should have changed');
@@ -485,7 +482,7 @@ describe('dest stream', function () {
       stream.end();
    });
 
-   it('should allow piping multiple dests in streaming mode', function (done) {
+   it('should allow piping multiple dests in streaming mode', done => {
       var inputPath1 = path.join(__dirname, "./out-fixtures/multiple-first");
       var inputPath2 = path.join(__dirname, "./out-fixtures/multiple-second");
       var inputBase = path.join(__dirname, "./out-fixtures/");
@@ -493,20 +490,20 @@ describe('dest stream', function () {
       var stream1 = vfs.dest('./out-fixtures/', { cwd: __dirname });
       var stream2 = vfs.dest('./out-fixtures/', { cwd: __dirname });
       var content = fs.readFileSync(srcPath);
-      var rename = through.obj(function (file: any, _: any, next: any) {
+      var rename = through.obj((file: any, _: any, next: any) => {
          file.path = inputPath2;
          this.push(file);
          next();
       });
 
-      stream1.on('data', function (file: any) {
+      stream1.on('data', (file: any) => {
          file.path.should.equal(inputPath1);
       });
 
       stream1.pipe(rename).pipe(stream2);
-      stream2.on('data', function (file: any) {
+      stream2.on('data', (file: any) => {
          file.path.should.equal(inputPath2);
-      }).once('end', function () {
+      }).once('end', () => {
          fs.readFileSync(inputPath1, 'utf8').should.equal(content.toString());
          fs.readFileSync(inputPath2, 'utf8').should.equal(content.toString());
          done();
@@ -533,29 +530,29 @@ describe('dest stream', function () {
 var chmodSpy = spies.chmodSpy;
 var statSpy = spies.statSpy;
 
-var wipeOut = function (cb: any) {
+var wipeOut = (cb: any) => {
    rimraf(path.join(__dirname, './out-fixtures/'), cb);
    spies.setError('false');
    statSpy.reset();
    chmodSpy.reset();
 };
 
-var dataWrap = function (fn: any) {
-   return function (data: any, enc: any, cb: any) {
+var dataWrap = (fn: any) => {
+   return (data: any, enc: any, cb: any) => {
       fn(data);
       cb();
    };
 };
 
-var realMode = function (n: any) {
+var realMode = (n: any) => {
    return n & parseInt("07777", 8);
 };
 
-describe('symlink stream', function () {
+describe('symlink stream', () => {
    beforeEach(wipeOut);
    afterEach(wipeOut);
 
-   it('should explode on invalid folder', function (done: any) {
+   it('should explode on invalid folder', (done: any) => {
       var stream: any;
       try {
          stream = gulp.symlink();
@@ -566,7 +563,7 @@ describe('symlink stream', function () {
       }
    });
 
-   it('should pass through writes with cwd', function (done) {
+   it('should pass through writes with cwd', done => {
       var inputPath = path.join(__dirname, './fixtures/test.coffee');
 
       var expectedFile = new File({
@@ -576,7 +573,7 @@ describe('symlink stream', function () {
          contents: null
       });
 
-      var onEnd = function () {
+      var onEnd = () => {
          buffered.length.should.equal(1);
          buffered[0].should.equal(expectedFile);
          done();
@@ -591,7 +588,7 @@ describe('symlink stream', function () {
       stream.end();
    });
 
-   it('should pass through writes with default cwd', function (done) {
+   it('should pass through writes with default cwd', done => {
       var inputPath = path.join(__dirname, './fixtures/test.coffee');
 
       var expectedFile = new File({
@@ -601,7 +598,7 @@ describe('symlink stream', function () {
          contents: null
       });
 
-      var onEnd = function () {
+      var onEnd = () => {
          buffered.length.should.equal(1);
          buffered[0].should.equal(expectedFile);
          done();
@@ -616,7 +613,7 @@ describe('symlink stream', function () {
       stream.end();
    });
 
-   it('should make link to the right folder with relative cwd', function (done) {
+   it('should make link to the right folder with relative cwd', done => {
       var inputPath = path.join(__dirname, './fixtures/test.coffee');
       var inputBase = path.join(__dirname, './fixtures/');
       var expectedPath = path.join(__dirname, './out-fixtures/test.coffee');
@@ -631,7 +628,7 @@ describe('symlink stream', function () {
          contents: expectedContents
       });
 
-      var onEnd = function () {
+      var onEnd = () => {
          buffered.length.should.equal(1);
          buffered[0].should.equal(expectedFile);
          buffered[0].cwd.should.equal(__dirname, 'cwd should have changed');
@@ -652,7 +649,7 @@ describe('symlink stream', function () {
       stream.end();
    });
 
-   it('should write buffer files to the right folder with function and relative cwd', function (done) {
+   it('should write buffer files to the right folder with function and relative cwd', done => {
       var inputPath = path.join(__dirname, './fixtures/test.coffee');
       var inputBase = path.join(__dirname, './fixtures/');
       var expectedPath = path.join(__dirname, './out-fixtures/test.coffee');
@@ -667,7 +664,7 @@ describe('symlink stream', function () {
          contents: expectedContents
       });
 
-      var onEnd = function () {
+      var onEnd = () => {
          buffered.length.should.equal(1);
          buffered[0].should.equal(expectedFile);
          buffered[0].cwd.should.equal(__dirname, 'cwd should have changed');
@@ -679,7 +676,7 @@ describe('symlink stream', function () {
          done();
       };
 
-      var stream = vfs.symlink(function (file) {
+      var stream = vfs.symlink(file => {
          should.exist(file);
          file.should.equal(expectedFile);
          return './out-fixtures';
@@ -692,7 +689,7 @@ describe('symlink stream', function () {
       stream.end();
    });
 
-   it('should write buffer files to the right folder', function (done) {
+   it('should write buffer files to the right folder', done => {
       var inputPath = path.join(__dirname, './fixtures/test.coffee');
       var inputBase = path.join(__dirname, './fixtures/');
       var expectedPath = path.join(__dirname, './out-fixtures/test.coffee');
@@ -711,7 +708,7 @@ describe('symlink stream', function () {
          }
       });
 
-      var onEnd = function () {
+      var onEnd = () => {
          buffered.length.should.equal(1);
          buffered[0].should.equal(expectedFile);
          buffered[0].cwd.should.equal(__dirname, 'cwd should have changed');
@@ -732,7 +729,7 @@ describe('symlink stream', function () {
       stream.end();
    });
 
-   it('should write streaming files to the right folder', function (done) {
+   it('should write streaming files to the right folder', done => {
       var inputPath = path.join(__dirname, './fixtures/test.coffee');
       var inputBase = path.join(__dirname, './fixtures/');
       var expectedPath = path.join(__dirname, './out-fixtures/test.coffee');
@@ -752,7 +749,7 @@ describe('symlink stream', function () {
          }
       });
 
-      var onEnd = function () {
+      var onEnd = () => {
          buffered.length.should.equal(1);
          buffered[0].should.equal(expectedFile);
          buffered[0].cwd.should.equal(__dirname, 'cwd should have changed');
@@ -770,14 +767,14 @@ describe('symlink stream', function () {
       bufferStream = through.obj(dataWrap(buffered.push.bind(buffered)), onEnd);
       stream.pipe(bufferStream);
       stream.write(expectedFile);
-      setTimeout(function () {
+      setTimeout(() => {
          contentStream.write(expectedContents);
          contentStream.end();
       }, 100);
       stream.end();
    });
 
-   it('should write directories to the right folder', function (done) {
+   it('should write directories to the right folder', done => {
       var inputPath = path.join(__dirname, './fixtures/wow');
       var inputBase = path.join(__dirname, './fixtures/');
       var expectedPath = path.join(__dirname, './out-fixtures/wow');
@@ -796,7 +793,7 @@ describe('symlink stream', function () {
          }
       });
 
-      var onEnd = function () {
+      var onEnd = () => {
          buffered.length.should.equal(1);
          buffered[0].should.equal(expectedFile);
          buffered[0].cwd.should.equal(__dirname, 'cwd should have changed');
@@ -817,7 +814,7 @@ describe('symlink stream', function () {
       stream.end();
    });
 
-   it('should use different modes for files and directories', function (done) {
+   it('should use different modes for files and directories', done => {
       var inputBase = path.join(__dirname, './fixtures');
       var inputPath = path.join(__dirname, './fixtures/wow/suchempty');
       var expectedBase = path.join(__dirname, './out-fixtures/wow');
@@ -831,7 +828,7 @@ describe('symlink stream', function () {
          stat: fs.statSync(inputPath)
       });
 
-      var onEnd = function () {
+      var onEnd = () => {
          realMode(fs.lstatSync(expectedBase).mode).should.equal(expectedDirMode);
          realMode(buffered[0].stat.mode).should.equal(expectedFileMode);
          done();
@@ -851,7 +848,7 @@ describe('symlink stream', function () {
       stream.end();
    });
 
-   it('should report IO errors', function (done) {
+   it('should report IO errors', done => {
       var inputPath = path.join(__dirname, './fixtures/test.coffee');
       var inputBase = path.join(__dirname, './fixtures/');
       var expectedPath = path.join(__dirname, './out-fixtures/test.coffee');
@@ -874,19 +871,19 @@ describe('symlink stream', function () {
       fs.chmodSync(expectedBase, 0);
 
       var stream = vfs.symlink('./out-fixtures/', { cwd: __dirname });
-      stream.on('error', function (err: any) {
+      stream.on('error', (err: any) => {
          err.code.should.equal('EACCES');
          done();
       });
       stream.write(expectedFile);
    });
 
-   ['end', 'finish'].forEach(function (eventName) {
-      it('should emit ' + eventName + ' event', function (done) {
+   ['end', 'finish'].forEach(eventName => {
+      it('should emit ' + eventName + ' event', done => {
          var srcPath = path.join(__dirname, './fixtures/test.coffee');
          var stream = vfs.symlink('./out-fixtures/', { cwd: __dirname });
 
-         stream.on(eventName, function () {
+         stream.on(eventName, () => {
             done();
          });
 
@@ -900,7 +897,7 @@ describe('symlink stream', function () {
          stream.end();
       });
    });
-   it('should check if it"s a vinyl file', function () {
+   it('should check if it"s a vinyl file', () => {
       var srcPath = path.join(__dirname, './fixtures/test.coffee');
       var options = {
          path: srcPath,