chore: use let/const instead of var

Author: Trott

benchmark/benchmark.js

@@ -1,4 +1,4 @@
-var slug = require('../slug')
+const slug = require('../slug')
 
 const BENCHMARK_RUNS = 2048
 const MAX_WORD_LENGTH = 16

slug.js

@@ -1,6 +1,6 @@
 /* global btoa */
 (function (root) {
-  var base64
+  let base64
 
   // This function's sole purpose is to help us ignore lone surrogates so that
   // malformed strings don't throw in the browser while being processed
@@ -60,9 +60,10 @@
       // Polyfill for environments that don't have btoa or Buffer class (notably, React Native).
       // Based on https://github.com/davidchambers/Base64.js/blob/a121f75bb10c8dd5d557886c4b1069b31258d230/base64.js
       base64 = function (input) {
-        var str = unescape(encodeURIComponent(input + ''))
+        const str = unescape(encodeURIComponent(input + ''))
+        let output = ''
         for (
-          var block, charCode, idx = 0, map = 'ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/=', output = '';
+          let block, charCode, idx = 0, map = 'ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/=';
           str.charAt(idx | 0) || (map = '=', idx % 1);
           output += map.charAt(63 & block >> 8 - idx % 1 * 8)
         ) {
@@ -95,12 +96,13 @@
           throw new TypeError('Cannot convert undefined or null to object')
         }
 
-        var to = Object(target)
+        const to = Object(target)
 
-        for (var index = 1; index < arguments.length; index++) {
-          var nextSource = arguments[index]
+        for (let index = 1; index < arguments.length; index++) {
+          const nextSource = arguments[index]
 
           if (nextSource !== null && nextSource !== undefined) {
+            // eslint-disable-next-line no-var
             for (var nextKey in nextSource) {
               // Avoid bugs when hasOwnProperty is shadowed
               if (Object.prototype.hasOwnProperty.call(nextSource, nextKey)) {
@@ -117,7 +119,7 @@
   }
 
   function slug (string, opts) {
-    var result = slugify(string, opts)
+    let result = slugify(string, opts)
     // If output is an empty string, try slug for base64 of string.
     if (result === '') {
       // Get rid of lone surrogates.
@@ -148,34 +150,34 @@
     if (typeof opts === 'string') { opts = { replacement: opts } }
     opts = opts ? Object.assign({}, opts) : {}
     opts.mode = opts.mode || slug.defaults.mode
-    var defaults = slug.defaults.modes[opts.mode]
-    var keys = ['replacement', 'multicharmap', 'charmap', 'remove', 'lower']
+    const defaults = slug.defaults.modes[opts.mode]
+    const keys = ['replacement', 'multicharmap', 'charmap', 'remove', 'lower']
     for (let key, i = 0, l = keys.length; i < l; i++) {
       key = keys[i]
       opts[key] = (key in opts) ? opts[key] : defaults[key]
     }
     const localeMap = locales[opts.locale] || {}
 
-    var lengths = []
+    let lengths = []
     // "let" instead of "const" in next line is for IE11 compatibilty
     for (let key in opts.multicharmap) { // eslint-disable-line prefer-const
       if (!Object.prototype.hasOwnProperty.call(opts.multicharmap, key)) { continue }
 
-      var len = key.length
+      const len = key.length
       if (lengths.indexOf(len) === -1) { lengths.push(len) }
     }
 
     // We want to match the longest string if there are multiple matches, so
     // sort lengths in descending order.
     lengths = lengths.sort(function (a, b) { return b - a })
 
-    var result = ''
+    let result = ''
     for (let char, i = 0, l = string.length; i < l; i++) {
       char = string[i]
       let matchedMultichar = false
       for (let j = 0; j < lengths.length; j++) {
         const len = lengths[j]
-        var str = string.substr(i, len)
+        const str = string.substr(i, len)
         if (opts.multicharmap[str]) {
           i += len - 1
           char = opts.multicharmap[str]

test/fuzz.test.js

@@ -1,12 +1,12 @@
 /* global chai, describe, it, window */
 
-var slug = (typeof window !== 'undefined' && window.slug) || require('../slug')
-var assert = typeof chai === 'undefined' ? require('assert') : chai.assert
+const slug = (typeof window !== 'undefined' && window.slug) || require('../slug')
+const assert = typeof chai === 'undefined' ? require('assert') : chai.assert
 
 // IE11 polyfill
 if (!Array.from) {
   Array.from = (function () {
-    var symbolIterator
+    let symbolIterator
     try {
       symbolIterator = Symbol.iterator
         ? Symbol.iterator
@@ -15,33 +15,33 @@ if (!Array.from) {
       symbolIterator = 'Symbol(Symbol.iterator)'
     }
 
-    var toStr = Object.prototype.toString
-    var isCallable = function (fn) {
+    const toStr = Object.prototype.toString
+    const isCallable = function (fn) {
       return (
         typeof fn === 'function' ||
               toStr.call(fn) === '[object Function]'
       )
     }
-    var toInteger = function (value) {
-      var number = Number(value)
+    const toInteger = function (value) {
+      const number = Number(value)
       if (isNaN(number)) return 0
       if (number === 0 || !isFinite(number)) return number
       return (number > 0 ? 1 : -1) * Math.floor(Math.abs(number))
     }
-    var maxSafeInteger = Math.pow(2, 53) - 1
-    var toLength = function (value) {
-      var len = toInteger(value)
+    const maxSafeInteger = Math.pow(2, 53) - 1
+    const toLength = function (value) {
+      const len = toInteger(value)
       return Math.min(Math.max(len, 0), maxSafeInteger)
     }
 
-    var setGetItemHandler = function setGetItemHandler (isIterator, items) {
-      var iterator = isIterator && items[symbolIterator]()
+    const setGetItemHandler = function setGetItemHandler (isIterator, items) {
+      const iterator = isIterator && items[symbolIterator]()
       return function getItem (k) {
         return isIterator ? iterator.next() : items[k]
       }
     }
 
-    var getArray = function getArray (
+    const getArray = function getArray (
       T,
       A,
       len,
@@ -50,13 +50,13 @@ if (!Array.from) {
       mapFn
     ) {
       // 16. Let k be 0.
-      var k = 0
+      let k = 0
 
       // 17. Repeat, while k < len… or while iterator is done (also steps a - h)
       // eslint-disable-next-line no-unmodified-loop-condition
       while (k < len || isIterator) {
-        var item = getItem(k)
-        var kValue = isIterator ? item.value : item
+        const item = getItem(k)
+        const kValue = isIterator ? item.value : item
 
         if (isIterator && item.done) {
           return A
@@ -87,11 +87,11 @@ if (!Array.from) {
     // The length property of the from method is 1.
     return function from (arrayLikeOrIterator /*, mapFn, thisArg */) {
       // 1. Let C be the this value.
-      var C = this
+      const C = this
 
       // 2. Let items be ToObject(arrayLikeOrIterator).
-      var items = Object(arrayLikeOrIterator)
-      var isIterator = isCallable(items[symbolIterator])
+      const items = Object(arrayLikeOrIterator)
+      const isIterator = isCallable(items[symbolIterator])
 
       // 3. ReturnIfAbrupt(items).
       if (arrayLikeOrIterator == null && !isIterator) {
@@ -102,8 +102,8 @@ if (!Array.from) {
 
       // 4. If mapfn is undefined, then let mapping be false.
       // eslint-disable-next-line no-void
-      var mapFn = arguments.length > 1 ? arguments[1] : void undefined
-      var T
+      const mapFn = arguments.length > 1 ? arguments[1] : void undefined
+      let T
       if (typeof mapFn !== 'undefined') {
         // 5. else
         // 5. a If IsCallable(mapfn) is false, throw a TypeError exception.
@@ -121,13 +121,13 @@ if (!Array.from) {
 
       // 10. Let lenValue be Get(items, "length").
       // 11. Let len be ToLength(lenValue).
-      var len = toLength(items.length)
+      const len = toLength(items.length)
 
       // 13. If IsConstructor(C) is true, then
       // 13. a. Let A be the result of calling the [[Construct]] internal method
       // of C with an argument list containing the single item len.
       // 14. a. Else, Let A be ArrayCreate(len).
-      var A = isCallable(C) ? Object(new C(len)) : new Array(len)
+      const A = isCallable(C) ? Object(new C(len)) : new Array(len)
 
       return getArray(
         T,

test/slug.test.js

@@ -5,10 +5,10 @@ const inBrowser = typeof window !== 'undefined'
 // Polyfill for IE11.
 if (!String.fromCodePoint) {
   (function (stringFromCharCode) {
-    var fromCodePoint = function (_) {
-      var codeUnits = []; var codeLen = 0; var result = ''
-      for (var index = 0, len = arguments.length; index !== len; ++index) {
-        var codePoint = +arguments[index]
+    const fromCodePoint = function (_) {
+      const codeUnits = []; let codeLen = 0; let result = ''
+      for (let index = 0, len = arguments.length; index !== len; ++index) {
+        let codePoint = +arguments[index]
         // correctly handles all cases including `NaN`, `-Infinity`, `+Infinity`
         // The surrounding `!(...)` is required to correctly handle `NaN` cases
         // The (codePoint>>>0) === codePoint clause handles decimals and negatives