Convert var to const/let in src files

```
npm install -g jscodeshift
git clone https://github.com/cpojer/js-codemod.git
jscodeshift -t js-codemod/transforms/no-vars.js ./src
```

Author: aminya

src/babel.js

@@ -1,37 +1,37 @@
 'use strict';
 
-var crypto = require('crypto');
-var path = require('path');
-var defaultOptions = require('../static/babelrc.json');
+const crypto = require('crypto');
+const path = require('path');
+const defaultOptions = require('../static/babelrc.json');
 
-var babel = null;
-var babelVersionDirectory = null;
+let babel = null;
+let babelVersionDirectory = null;
 
-var PREFIXES = [
+const PREFIXES = [
   '/** @babel */',
   '"use babel"',
   "'use babel'",
   '/* @flow */',
   '// @flow'
 ];
 
-var PREFIX_LENGTH = Math.max.apply(
+const PREFIX_LENGTH = Math.max.apply(
   Math,
   PREFIXES.map(function(prefix) {
     return prefix.length;
   })
 );
 
 exports.shouldCompile = function(sourceCode) {
-  var start = sourceCode.substr(0, PREFIX_LENGTH);
+  const start = sourceCode.substr(0, PREFIX_LENGTH);
   return PREFIXES.some(function(prefix) {
     return start.indexOf(prefix) === 0;
   });
 };
 
 exports.getCachePath = function(sourceCode) {
   if (babelVersionDirectory == null) {
-    var babelVersion = require('babel-core/package.json').version;
+    const babelVersion = require('babel-core/package.json').version;
     babelVersionDirectory = path.join(
       'js',
       'babel',
@@ -51,8 +51,8 @@ exports.getCachePath = function(sourceCode) {
 exports.compile = function(sourceCode, filePath) {
   if (!babel) {
     babel = require('babel-core');
-    var Logger = require('babel-core/lib/transformation/file/logger');
-    var noop = function() {};
+    const Logger = require('babel-core/lib/transformation/file/logger');
+    const noop = function() {};
     Logger.prototype.debug = noop;
     Logger.prototype.verbose = noop;
   }
@@ -61,8 +61,8 @@ exports.compile = function(sourceCode, filePath) {
     filePath = 'file:///' + path.resolve(filePath).replace(/\\/g, '/');
   }
 
-  var options = { filename: filePath };
-  for (var key in defaultOptions) {
+  const options = { filename: filePath };
+  for (const key in defaultOptions) {
     options[key] = defaultOptions[key];
   }
   return babel.transform(sourceCode, options).code;

src/coffee-script.js

@@ -1,8 +1,8 @@
 'use strict';
 
-var crypto = require('crypto');
-var path = require('path');
-var CoffeeScript = null;
+const crypto = require('crypto');
+const path = require('path');
+let CoffeeScript = null;
 
 exports.shouldCompile = function() {
   return true;
@@ -20,7 +20,7 @@ exports.getCachePath = function(sourceCode) {
 
 exports.compile = function(sourceCode, filePath) {
   if (!CoffeeScript) {
-    var previousPrepareStackTrace = Error.prepareStackTrace;
+    const previousPrepareStackTrace = Error.prepareStackTrace;
     CoffeeScript = require('coffee-script');
 
     // When it loads, coffee-script reassigns Error.prepareStackTrace. We have
@@ -33,7 +33,7 @@ exports.compile = function(sourceCode, filePath) {
     filePath = 'file:///' + path.resolve(filePath).replace(/\\/g, '/');
   }
 
-  var output = CoffeeScript.compile(sourceCode, {
+  const output = CoffeeScript.compile(sourceCode, {
     filename: filePath,
     sourceFiles: [filePath],
     inlineMap: true

src/compile-cache.js

@@ -5,16 +5,16 @@
 // Atom's compile-cache when installing or updating packages, using an older
 // version of node.js
 
-var path = require('path');
-var fs = require('fs-plus');
-var sourceMapSupport = require('@atom/source-map-support');
+const path = require('path');
+const fs = require('fs-plus');
+const sourceMapSupport = require('@atom/source-map-support');
 
-var PackageTranspilationRegistry = require('./package-transpilation-registry');
-var CSON = null;
+const PackageTranspilationRegistry = require('./package-transpilation-registry');
+let CSON = null;
 
-var packageTranspilationRegistry = new PackageTranspilationRegistry();
+const packageTranspilationRegistry = new PackageTranspilationRegistry();
 
-var COMPILERS = {
+const COMPILERS = {
   '.js': packageTranspilationRegistry.wrapTranspiler(require('./babel')),
   '.ts': packageTranspilationRegistry.wrapTranspiler(require('./typescript')),
   '.tsx': packageTranspilationRegistry.wrapTranspiler(require('./typescript')),
@@ -43,11 +43,11 @@ exports.removeTranspilerConfigForPath = function(packagePath) {
   packageTranspilationRegistry.removeTranspilerConfigForPath(packagePath);
 };
 
-var cacheStats = {};
-var cacheDirectory = null;
+const cacheStats = {};
+let cacheDirectory = null;
 
 exports.setAtomHomeDirectory = function(atomHome) {
-  var cacheDir = path.join(atomHome, 'compile-cache');
+  let cacheDir = path.join(atomHome, 'compile-cache');
   if (
     process.env.USER === 'root' &&
     process.env.SUDO_USER &&
@@ -68,7 +68,7 @@ exports.getCacheDirectory = function() {
 
 exports.addPathToCache = function(filePath, atomHome) {
   this.setAtomHomeDirectory(atomHome);
-  var extension = path.extname(filePath);
+  const extension = path.extname(filePath);
 
   if (extension === '.cson') {
     if (!CSON) {
@@ -77,7 +77,7 @@ exports.addPathToCache = function(filePath, atomHome) {
     }
     return CSON.readFileSync(filePath);
   } else {
-    var compiler = COMPILERS[extension];
+    const compiler = COMPILERS[extension];
     if (compiler) {
       return compileFileAtPath(compiler, filePath, extension);
     }
@@ -98,10 +98,10 @@ exports.resetCacheStats = function() {
 };
 
 function compileFileAtPath(compiler, filePath, extension) {
-  var sourceCode = fs.readFileSync(filePath, 'utf8');
+  const sourceCode = fs.readFileSync(filePath, 'utf8');
   if (compiler.shouldCompile(sourceCode, filePath)) {
-    var cachePath = compiler.getCachePath(sourceCode, filePath);
-    var compiledCode = readCachedJavaScript(cachePath);
+    const cachePath = compiler.getCachePath(sourceCode, filePath);
+    let compiledCode = readCachedJavaScript(cachePath);
     if (compiledCode != null) {
       cacheStats[extension].hits++;
     } else {
@@ -115,7 +115,7 @@ function compileFileAtPath(compiler, filePath, extension) {
 }
 
 function readCachedJavaScript(relativeCachePath) {
-  var cachePath = path.join(cacheDirectory, relativeCachePath);
+  const cachePath = path.join(cacheDirectory, relativeCachePath);
   if (fs.isFileSync(cachePath)) {
     try {
       return fs.readFileSync(cachePath, 'utf8');
@@ -125,11 +125,11 @@ function readCachedJavaScript(relativeCachePath) {
 }
 
 function writeCachedJavaScript(relativeCachePath, code) {
-  var cachePath = path.join(cacheDirectory, relativeCachePath);
+  const cachePath = path.join(cacheDirectory, relativeCachePath);
   fs.writeFileSync(cachePath, code, 'utf8');
 }
 
-var INLINE_SOURCE_MAP_REGEXP = /\/\/[#@]\s*sourceMappingURL=([^'"\n]+)\s*$/gm;
+const INLINE_SOURCE_MAP_REGEXP = /\/\/[#@]\s*sourceMappingURL=([^'"\n]+)\s*$/gm;
 
 exports.install = function(resourcesPath, nodeRequire) {
   const snapshotSourceMapConsumer = {
@@ -166,7 +166,7 @@ exports.install = function(resourcesPath, nodeRequire) {
         return null;
       }
 
-      var compiler = COMPILERS[path.extname(filePath)];
+      let compiler = COMPILERS[path.extname(filePath)];
       if (!compiler) compiler = COMPILERS['.js'];
 
       try {
@@ -182,7 +182,7 @@ exports.install = function(resourcesPath, nodeRequire) {
         return null;
       }
 
-      var match, lastMatch;
+      let match, lastMatch;
       INLINE_SOURCE_MAP_REGEXP.lastIndex = 0;
       while ((match = INLINE_SOURCE_MAP_REGEXP.exec(fileData))) {
         lastMatch = match;
@@ -191,8 +191,8 @@ exports.install = function(resourcesPath, nodeRequire) {
         return null;
       }
 
-      var sourceMappingURL = lastMatch[1];
-      var rawData = sourceMappingURL.slice(sourceMappingURL.indexOf(',') + 1);
+      const sourceMappingURL = lastMatch[1];
+      const rawData = sourceMappingURL.slice(sourceMappingURL.indexOf(',') + 1);
 
       try {
         var sourceMap = JSON.parse(Buffer.from(rawData, 'base64'));
@@ -208,7 +208,7 @@ exports.install = function(resourcesPath, nodeRequire) {
     }
   });
 
-  var prepareStackTraceWithSourceMapping = Error.prepareStackTrace;
+  const prepareStackTraceWithSourceMapping = Error.prepareStackTrace;
   var prepareStackTrace = prepareStackTraceWithSourceMapping;
 
   function prepareStackTraceWithRawStackAssignment(error, frames) {
@@ -245,13 +245,13 @@ exports.install = function(resourcesPath, nodeRequire) {
   };
 
   Object.keys(COMPILERS).forEach(function(extension) {
-    var compiler = COMPILERS[extension];
+    const compiler = COMPILERS[extension];
 
     Object.defineProperty(nodeRequire.extensions, extension, {
       enumerable: true,
       writable: false,
       value: function(module, filePath) {
-        var code = compileFileAtPath(compiler, filePath, extension);
+        const code = compileFileAtPath(compiler, filePath, extension);
         return module._compile(code, filePath);
       }
     });

src/delegated-listener.js

@@ -1,7 +1,7 @@
 const EventKit = require('event-kit');
 
 module.exports = function listen(element, eventName, selector, handler) {
-  var innerHandler = function(event) {
+  const innerHandler = function(event) {
     if (selector) {
       var currentTarget = event.target;
       while (currentTarget) {

src/history-manager.js

@@ -89,7 +89,7 @@ class HistoryManager {
   }
 
   getProject(paths) {
-    for (var i = 0; i < this.projects.length; i++) {
+    for (let i = 0; i < this.projects.length; i++) {
       if (arrayEquivalent(paths, this.projects[i].paths)) {
         return this.projects[i];
       }
@@ -121,7 +121,7 @@ class HistoryManager {
 
 function arrayEquivalent(a, b) {
   if (a.length !== b.length) return false;
-  for (var i = 0; i < a.length; i++) {
+  for (let i = 0; i < a.length; i++) {
     if (a[i] !== b[i]) return false;
   }
   return true;

src/module-cache.js

@@ -73,7 +73,7 @@ function loadDependencies(modulePath, rootPath, rootMetadata, moduleCache) {
 
     const childMetadata = JSON.parse(fs.readFileSync(childMetadataPath));
     if (childMetadata && childMetadata.version) {
-      var mainPath;
+      let mainPath;
       try {
         mainPath = require.resolve(childPath);
       } catch (error) {

src/package-manager.js

@@ -531,7 +531,7 @@ module.exports = class PackageManager {
     ) => {
       for (const packageName of packageNames) {
         if (!disabledPackageNames.has(packageName)) {
-          var pack = this.getLoadedPackage(packageName);
+          const pack = this.getLoadedPackage(packageName);
           if (pack != null) {
             action(pack);
           }

src/package.js

@@ -1173,7 +1173,7 @@ module.exports = class Package {
       return nativeModulePaths;
     }
 
-    var traversePath = nodeModulesPath => {
+    const traversePath = nodeModulesPath => {
       try {
         for (let modulePath of fs.listSync(nodeModulesPath)) {
           const modulePathNodeFiles = this.getModulePathNodeFiles(modulePath);

src/state-store.js

@@ -43,7 +43,7 @@ module.exports = class StateStore {
       this.dbPromise.then(db => {
         if (db == null) return resolve();
 
-        var request = db
+        const request = db
           .transaction(['states'], 'readwrite')
           .objectStore('states')
           .put({ value: value, storedAt: new Date().toString() }, key);
@@ -59,7 +59,7 @@ module.exports = class StateStore {
       if (!db) return;
 
       return new Promise((resolve, reject) => {
-        var request = db
+        const request = db
           .transaction(['states'])
           .objectStore('states')
           .get(key);
@@ -83,7 +83,7 @@ module.exports = class StateStore {
       this.dbPromise.then(db => {
         if (db == null) return resolve();
 
-        var request = db
+        const request = db
           .transaction(['states'], 'readwrite')
           .objectStore('states')
           .delete(key);
@@ -99,7 +99,7 @@ module.exports = class StateStore {
       if (!db) return;
 
       return new Promise((resolve, reject) => {
-        var request = db
+        const request = db
           .transaction(['states'], 'readwrite')
           .objectStore('states')
           .clear();
@@ -115,7 +115,7 @@ module.exports = class StateStore {
       if (!db) return;
 
       return new Promise((resolve, reject) => {
-        var request = db
+        const request = db
           .transaction(['states'])
           .objectStore('states')
           .count();

src/style-manager.js

@@ -254,7 +254,7 @@ module.exports = class StyleManager {
   }
 
   buildStylesElement() {
-    var stylesElement = new StylesElement();
+    const stylesElement = new StylesElement();
     stylesElement.initialize(this);
     return stylesElement;
   }