[internal] Replace var assignments with let in non-ui

This change was applied to all directories under src/ except for the ui/
directory. Only .js files were searched.

This was an automatic replacement from var to let for any variable
declaration that doubles as the initial assignment. Ultimately we want
most of these to be converted to const, but this commit is so large that
it warrants breaking each step of automation up into its own commit.

For example:

`var foo = 'bar';` becomes `let foo = 'var';`

This was accomplished by replacing:
find:    `var ([a-zA-Z_$][0-9a-zA-Z_$]*)(\s+)=`
replace: `let $1$2=`

src/cli/command.js

@@ -82,7 +82,7 @@ Command.prototype.parseOptions = _.wrap(Command.prototype.parseOptions, function
 
 Command.prototype.action = _.wrap(Command.prototype.action, function (action, fn) {
   return action.call(this, function (...args) {
-    var ret = fn.apply(this, args);
+    let ret = fn.apply(this, args);
     if (ret && typeof ret.then === 'function') {
       ret.then(null, function (e) {
         console.log('FATAL CLI ERROR', e.stack);

src/cli/help.js

@@ -69,6 +69,6 @@ ${indent(cmd.optionHelp(), 2)}
 }
 
 function humanReadableArgName(arg) {
-  var nameOutput = arg.name + (arg.variadic === true ? '...' : '');
+  let nameOutput = arg.name + (arg.variadic === true ? '...' : '');
   return arg.required ? '<' + nameOutput + '>' : '[' + nameOutput + ']';
 }

src/cli_plugin/cli.js

@@ -23,7 +23,7 @@ program
 .command('help <command>')
 .description('get the help for a specific command')
 .action(function (cmdName) {
-  var cmd = _.find(program.commands, { _name: cmdName });
+  let cmd = _.find(program.commands, { _name: cmdName });
   if (!cmd) return program.error(`unknown command ${cmdName}`);
   cmd.help();
 });
@@ -35,7 +35,7 @@ program
 });
 
 // check for no command name
-var subCommand = argv[2] && !String(argv[2][0]).match(/^-|^\.|\//);
+let subCommand = argv[2] && !String(argv[2][0]).match(/^-|^\.|\//);
 if (!subCommand) {
   program.defaultHelp();
 }

src/fixtures/agg_resp/geohash_grid.js

@@ -17,23 +17,23 @@ export default function GeoHashGridAggResponseFixture() {
   //   },
   // });
 
-  var geoHashCharts = _.union(
+  let geoHashCharts = _.union(
     _.range(48, 57), // 0-9
     _.range(65, 90), // A-Z
     _.range(97, 122) // a-z
   );
 
-  var totalDocCount = 0;
+  let totalDocCount = 0;
 
-  var tags = _.times(_.random(4, 20), function (i) {
+  let tags = _.times(_.random(4, 20), function (i) {
     // random number of tags
-    var docCount = 0;
-    var buckets = _.times(_.random(40, 200), function () {
+    let docCount = 0;
+    let buckets = _.times(_.random(40, 200), function () {
       return _.sample(geoHashCharts, 3).join('');
     })
     .sort()
     .map(function (geoHash) {
-      var count = _.random(1, 5000);
+      let count = _.random(1, 5000);
 
       totalDocCount += count;
       docCount += count;

src/fixtures/fake_chart_events.js

@@ -1,4 +1,4 @@
-var results = {};
+let results = {};
 
 results.timeSeries = {
   data: {

src/fixtures/fake_hierarchical_data.js

@@ -1,4 +1,4 @@
-var data = {  };
+let data = {  };
 
 data.metricOnly = {
   hits: { total: 1000, hits: [], max_score: 0 },

src/fixtures/fake_row.js

@@ -1,5 +1,5 @@
 import _ from 'lodash';
-var longString = Array(200).join('_');
+let longString = Array(200).join('_');
 
 export default function (id, mapping) {
   function fakeVals(type) {

src/fixtures/logstash_fields.js

@@ -1,5 +1,5 @@
 function stubbedLogstashFields() {
-  var sourceData = [
+  let sourceData = [
     { name: 'bytes',              type: 'number',     indexed: true,  analyzed: true, sortable:  true,  filterable: true,   count: 10 },
     { name: 'ssl',                type: 'boolean',    indexed: true,  analyzed: true, sortable:  true,  filterable: true,   count: 20 },
     { name: '@timestamp',         type: 'date',       indexed: true,  analyzed: true, sortable:  true,  filterable: true,   count: 30 },

src/fixtures/mock_courier.js

@@ -3,11 +3,11 @@ import sinon from 'auto-release-sinon';
 import FixturesStubbedLogstashIndexPatternProvider from 'fixtures/stubbed_logstash_index_pattern';
 
 export default function (Private, Promise) {
-  var indexPatterns = Private(FixturesStubbedLogstashIndexPatternProvider);
-  var getIndexPatternStub = sinon.stub();
+  let indexPatterns = Private(FixturesStubbedLogstashIndexPatternProvider);
+  let getIndexPatternStub = sinon.stub();
   getIndexPatternStub.returns(Promise.resolve(indexPatterns));
 
-  var courier = {
+  let courier = {
     indexPatterns: { get: getIndexPatternStub },
     getStub: getIndexPatternStub
   };

src/fixtures/mock_ui_state.js

@@ -1,5 +1,5 @@
 import _ from 'lodash';
-var keys = {};
+let keys = {};
 export default {
   get: function (path, def) {
     return keys[path] == null ? def : keys[path];

src/fixtures/stubbed_doc_source_response.js

@@ -1,7 +1,7 @@
 import FixturesLogstashFieldsProvider from 'fixtures/logstash_fields';
 
 function stubbedDocSourceResponse(Private) {
-  var mockLogstashFields = Private(FixturesLogstashFieldsProvider);
+  let mockLogstashFields = Private(FixturesLogstashFieldsProvider);
 
   return function (id, index) {
     index = index || '.kibana';

src/fixtures/stubbed_logstash_index_pattern.js

@@ -3,21 +3,21 @@ import TestUtilsStubIndexPatternProvider from 'test_utils/stub_index_pattern';
 import IndexPatternsFieldTypesProvider from 'ui/index_patterns/_field_types';
 import FixturesLogstashFieldsProvider from 'fixtures/logstash_fields';
 export default function stubbedLogstashIndexPatternService(Private) {
-  var StubIndexPattern = Private(TestUtilsStubIndexPatternProvider);
-  var fieldTypes = Private(IndexPatternsFieldTypesProvider);
-  var mockLogstashFields = Private(FixturesLogstashFieldsProvider);
+  let StubIndexPattern = Private(TestUtilsStubIndexPatternProvider);
+  let fieldTypes = Private(IndexPatternsFieldTypesProvider);
+  let mockLogstashFields = Private(FixturesLogstashFieldsProvider);
 
 
-  var fields = mockLogstashFields.map(function (field) {
+  let fields = mockLogstashFields.map(function (field) {
     field.displayName = field.name;
-    var type = fieldTypes.byName[field.type];
+    let type = fieldTypes.byName[field.type];
     if (!type) throw new TypeError('unknown type ' + field.type);
     if (!_.has(field, 'sortable')) field.sortable = type.sortable;
     if (!_.has(field, 'filterable')) field.filterable = type.filterable;
     return field;
   });
 
-  var indexPattern = new StubIndexPattern('logstash-*', 'time', fields);
+  let indexPattern = new StubIndexPattern('logstash-*', 'time', fields);
   indexPattern.id = 'logstash-*';
 
   return indexPattern;

src/fixtures/stubbed_search_source.js

@@ -3,8 +3,8 @@ import searchResponse from 'fixtures/search_response';
 import FixturesStubbedLogstashIndexPatternProvider from 'fixtures/stubbed_logstash_index_pattern';
 
 export default function stubSearchSource(Private, $q, Promise) {
-  var deferedResult = $q.defer();
-  var indexPattern = Private(FixturesStubbedLogstashIndexPatternProvider);
+  let deferedResult = $q.defer();
+  let indexPattern = Private(FixturesStubbedLogstashIndexPatternProvider);
 
   return {
     sort: sinon.spy(),

src/fixtures/vislib/_vis_fixture.js

@@ -2,7 +2,7 @@ import _ from 'lodash';
 import $ from 'jquery';
 import VislibVisProvider from 'ui/vislib/vis';
 
-var $visCanvas = $('<div>')
+let $visCanvas = $('<div>')
   .attr('id', 'vislib-vis-fixtures')
   .css({
     height: '500px',
@@ -15,8 +15,8 @@ var $visCanvas = $('<div>')
   })
   .appendTo('body');
 
-var count = 0;
-var visHeight = $visCanvas.height();
+let count = 0;
+let visHeight = $visCanvas.height();
 
 $visCanvas.new = function () {
   count += 1;
@@ -32,7 +32,7 @@ afterEach(function () {
 
 module.exports = function VislibFixtures(Private) {
   return function (visLibParams) {
-    var Vis = Private(VislibVisProvider);
+    let Vis = Private(VislibVisProvider);
     return new Vis($visCanvas.new(), _.defaults({}, visLibParams || {}, {
       shareYAxis: true,
       addTooltip: true,

src/optimize/babel_options.build.js

@@ -1,5 +1,5 @@
 import { cloneDeep } from 'lodash';
-var fromRoot = require('path').resolve.bind(null, __dirname, '../../');
+let fromRoot = require('path').resolve.bind(null, __dirname, '../../');
 
 if (!process.env.BABEL_CACHE_PATH) {
   process.env.BABEL_CACHE_PATH = fromRoot('optimize/.babelcache.json');

src/optimize/babel_options.js

@@ -1,5 +1,5 @@
-var cloneDeep = require('lodash').cloneDeep;
-var fromRoot = require('path').resolve.bind(null, __dirname, '../../');
+let cloneDeep = require('lodash').cloneDeep;
+let fromRoot = require('path').resolve.bind(null, __dirname, '../../');
 
 if (!process.env.BABEL_CACHE_PATH) {
   process.env.BABEL_CACHE_PATH = fromRoot('optimize/.babelcache.json');

src/plugins/kbn_doc_views/public/views/table.js

@@ -26,7 +26,7 @@ docViewsRegistry.register(function () {
         };
 
         $scope.showArrayInObjectsWarning = function (row, field) {
-          var value = $scope.flattened[field];
+          let value = $scope.flattened[field];
           return _.isArray(value) && typeof value[0] === 'object';
         };
       }

src/server/config/__tests__/config.js

@@ -9,12 +9,12 @@ import Joi from 'joi';
  *
  * Config should be newed up with a joi schema (containing defaults via joi)
  *
- * var schema = { ... }
+ * let schema = { ... }
  * new Config(schema);
  *
  */
 
-var data = {
+let data = {
   test: {
     hosts: ['host-01', 'host-02'],
     client: {
@@ -25,7 +25,7 @@ var data = {
   }
 };
 
-var schema = Joi.object({
+let schema = Joi.object({
   test: Joi.object({
     enable: Joi.boolean().default(true),
     hosts: Joi.array().items(Joi.string()),
@@ -44,39 +44,39 @@ describe('lib/config/config', function () {
     describe('constructor', function () {
 
       it('should not allow any config if the schema is not passed', function () {
-        var config = new Config();
-        var run = function () {
+        let config = new Config();
+        let run = function () {
           config.set('something.enable', true);
         };
         expect(run).to.throwException();
       });
 
       it('should allow keys in the schema', function () {
-        var config = new Config(schema);
-        var run = function () {
+        let config = new Config(schema);
+        let run = function () {
           config.set('test.client.host', 'http://0.0.0.0');
         };
         expect(run).to.not.throwException();
       });
 
       it('should not allow keys not in the schema', function () {
-        var config = new Config(schema);
-        var run = function () {
+        let config = new Config(schema);
+        let run = function () {
           config.set('paramNotDefinedInTheSchema', true);
         };
         expect(run).to.throwException();
       });
 
       it('should not allow child keys not in the schema', function () {
-        var config = new Config(schema);
-        var run = function () {
+        let config = new Config(schema);
+        let run = function () {
           config.set('test.client.paramNotDefinedInTheSchema', true);
         };
         expect(run).to.throwException();
       });
 
       it('should set defaults', function () {
-        var config = new Config(schema);
+        let config = new Config(schema);
         expect(config.get('test.enable')).to.be(true);
         expect(config.get('test.client.type')).to.be('datastore');
       });
@@ -92,7 +92,7 @@ describe('lib/config/config', function () {
 
       it('should reset the config object with new values', function () {
         config.set(data);
-        var newData = config.get();
+        let newData = config.get();
         newData.test.enable = false;
         config.resetTo(newData);
         expect(config.get()).to.eql(newData);
@@ -134,21 +134,21 @@ describe('lib/config/config', function () {
       });
 
       it('should use an object to set config values', function () {
-        var hosts = ['host-01', 'host-02'];
+        let hosts = ['host-01', 'host-02'];
         config.set({ test: { enable: false, hosts: hosts } });
         expect(config.get('test.enable')).to.be(false);
         expect(config.get('test.hosts')).to.eql(hosts);
       });
 
       it('should use a flatten object to set config values', function () {
-        var hosts = ['host-01', 'host-02'];
+        let hosts = ['host-01', 'host-02'];
         config.set({ 'test.enable': false, 'test.hosts': hosts });
         expect(config.get('test.enable')).to.be(false);
         expect(config.get('test.hosts')).to.eql(hosts);
       });
 
       it('should override values with just the values present', function () {
-        var newData = _.cloneDeep(data);
+        let newData = _.cloneDeep(data);
         config.set(data);
         newData.test.enable = false;
         config.set({ test: { enable: false } });
@@ -156,7 +156,7 @@ describe('lib/config/config', function () {
       });
 
       it('should thow an exception when setting a value with the wrong type', function (done) {
-        var run = function () {
+        let run = function () {
           config.set('test.enable', 'something');
         };
         expect(run).to.throwException(function (err) {
@@ -179,7 +179,7 @@ describe('lib/config/config', function () {
       });
 
       it('should return the whole config object when called without a key', function () {
-        var newData = _.cloneDeep(data);
+        let newData = _.cloneDeep(data);
         newData.test.enable = true;
         expect(config.get()).to.eql(newData);
       });
@@ -194,14 +194,14 @@ describe('lib/config/config', function () {
       });
 
       it('should throw exception for unknown config values', function () {
-        var run = function () {
+        let run = function () {
           config.get('test.does.not.exist');
         };
         expect(run).to.throwException(/Unknown config key: test.does.not.exist/);
       });
 
       it('should not throw exception for undefined known config values', function () {
-        var run = function getUndefValue() {
+        let run = function getUndefValue() {
           config.get('test.undefValue');
         };
         expect(run).to.not.throwException();
@@ -216,13 +216,13 @@ describe('lib/config/config', function () {
       });
 
       it('should allow you to extend the schema at the top level', function () {
-        var newSchema = Joi.object({ test: Joi.boolean().default(true) }).default();
+        let newSchema = Joi.object({ test: Joi.boolean().default(true) }).default();
         config.extendSchema('myTest', newSchema);
         expect(config.get('myTest.test')).to.be(true);
       });
 
       it('should allow you to extend the schema with a prefix', function () {
-        var newSchema = Joi.object({ test: Joi.boolean().default(true) }).default();
+        let newSchema = Joi.object({ test: Joi.boolean().default(true) }).default();
         config.extendSchema('prefix.myTest', newSchema);
         expect(config.get('prefix')).to.eql({ myTest: { test: true }});
         expect(config.get('prefix.myTest')).to.eql({ test: true });
@@ -230,8 +230,8 @@ describe('lib/config/config', function () {
       });
 
       it('should NOT allow you to extend the schema if somethign else is there', function () {
-        var newSchema = Joi.object({ test: Joi.boolean().default(true) }).default();
-        var run = function () {
+        let newSchema = Joi.object({ test: Joi.boolean().default(true) }).default();
+        let run = function () {
           config.extendSchema('test', newSchema);
         };
         expect(run).to.throwException();
@@ -241,7 +241,7 @@ describe('lib/config/config', function () {
 
     describe('#removeSchema(key)', function () {
       it('should completely remove the key', function () {
-        var config = new Config(Joi.object().keys({
+        let config = new Config(Joi.object().keys({
           a: Joi.number().default(1)
         }));
 
@@ -251,7 +251,7 @@ describe('lib/config/config', function () {
       });
 
       it('only removes existing keys', function () {
-        var config = new Config(Joi.object());
+        let config = new Config(Joi.object());
 
         expect(() => config.removeSchema('b')).to.throwException('Unknown schema');
       });

src/server/config/__tests__/explode_by.js

@@ -4,7 +4,7 @@ import expect from 'expect.js';
 describe('explode_by(dot, flatObject)', function () {
 
   it('should explode a flatten object with dots', function () {
-    var flatObject = {
+    let flatObject = {
       'test.enable': true,
       'test.hosts': ['host-01', 'host-02']
     };
@@ -17,7 +17,7 @@ describe('explode_by(dot, flatObject)', function () {
   });
 
   it('should explode a flatten object with slashes', function () {
-    var flatObject = {
+    let flatObject = {
       'test/enable': true,
       'test/hosts': ['host-01', 'host-02']
     };

src/server/config/__tests__/flatten_with.js

@@ -4,7 +4,7 @@ import expect from 'expect.js';
 describe('flatten_with(dot, nestedObj)', function () {
 
   it('should flatten object with dot', function () {
-    var nestedObj = {
+    let nestedObj = {
       test: {
         enable: true,
         hosts: ['host-01', 'host-02'],

src/server/config/__tests__/override.js

@@ -4,7 +4,7 @@ import expect from 'expect.js';
 describe('override(target, source)', function () {
 
   it('should override the values form source to target', function () {
-    var target = {
+    let target = {
       test: {
         enable: true,
         host: ['host-01', 'host-02'],
@@ -13,7 +13,7 @@ describe('override(target, source)', function () {
         }
       }
     };
-    var source = { test: { client: { type: 'nosql' } } };
+    let source = { test: { client: { type: 'nosql' } } };
     expect(override(target, source)).to.eql({
       test: {
         enable: true,

src/server/config/explode_by.js

@@ -1,10 +1,10 @@
 import _ from 'lodash';
 module.exports = function (dot, flatObject) {
-  var fullObject = {};
+  let fullObject = {};
   _.each(flatObject, function (value, key) {
-    var keys = key.split(dot);
+    let keys = key.split(dot);
     (function walk(memo, keys, value) {
-      var _key = keys.shift();
+      let _key = keys.shift();
       if (keys.length === 0) {
         memo[_key] = value;
       } else {

src/server/config/flatten_with.js

@@ -1,8 +1,8 @@
 import _ from 'lodash';
 module.exports = function (dot, nestedObj, flattenArrays) {
   let key; // original key
-  var stack = []; // track key stack
-  var flatObj = {};
+  let stack = []; // track key stack
+  let flatObj = {};
   (function flattenObj(obj) {
     _.keys(obj).forEach(function (key) {
       stack.push(key);

src/server/config/override.js

@@ -3,8 +3,8 @@ import flattenWith from './flatten_with';
 import explodeBy from './explode_by';
 
 module.exports = function (target, source) {
-  var _target = flattenWith('.', target);
-  var _source = flattenWith('.', source);
+  let _target = flattenWith('.', target);
+  let _source = flattenWith('.', source);
   return explodeBy('.', _.defaults(_source, _target));
 };
 

src/server/logging/__tests__/apply_filters_to_keys.js

@@ -3,7 +3,7 @@ import expect from 'expect.js';
 
 describe('applyFiltersToKeys(obj, actionsByKey)', function () {
   it('applies for each key+prop in actionsByKey', function () {
-    var data = applyFiltersToKeys({
+    let data = applyFiltersToKeys({
       a: {
         b: {
           c: 1

src/server/logging/apply_filters_to_keys.js

@@ -21,7 +21,7 @@ function apply(obj, key, action) {
           obj[k] = ('' + val).replace(/./g, 'X');
         }
         else if (/\/.+\//.test(action)) {
-          var matches = action.match(/\/(.+)\//);
+          let matches = action.match(/\/(.+)\//);
           if (matches) {
             let regex = new RegExp(matches[1]);
             obj[k] = ('' + val).replace(regex, replacer);

src/server/logging/log_format.js

@@ -41,13 +41,13 @@ module.exports = class TransformObjStream extends Stream.Transform {
   }
 
   _transform(event, enc, next) {
-    var data = this.filter(this.readEvent(event));
+    let data = this.filter(this.readEvent(event));
     this.push(this.format(data) + '\n');
     next();
   }
 
   readEvent(event) {
-    var data = {
+    let data = {
       type: event.event,
       '@timestamp': moment.utc(event.timestamp).format(),
       tags: [].concat(event.tags || []),
@@ -69,7 +69,7 @@ module.exports = class TransformObjStream extends Stream.Transform {
         referer: event.source.referer
       };
 
-      var contentLength = 0;
+      let contentLength = 0;
       if (typeof event.responsePayload === 'object') {
         contentLength = stringify(event.responsePayload).length;
       } else {
@@ -82,7 +82,7 @@ module.exports = class TransformObjStream extends Stream.Transform {
         contentLength: contentLength
       };
 
-      var query = querystring.stringify(event.query);
+      let query = querystring.stringify(event.query);
       if (query) data.req.url += '?' + query;
 
 

src/server/pid/index.js

@@ -2,19 +2,19 @@ import _ from 'lodash';
 import Boom from 'boom';
 import Promise from 'bluebird';
 import { unlinkSync as unlink } from 'fs';
-var writeFile = Promise.promisify(require('fs').writeFile);
+let writeFile = Promise.promisify(require('fs').writeFile);
 
 module.exports = Promise.method(function (kbnServer, server, config) {
-  var path = config.get('pid.file');
+  let path = config.get('pid.file');
   if (!path) return;
 
-  var pid = String(process.pid);
+  let pid = String(process.pid);
 
   return writeFile(path, pid, { flag: 'wx' })
   .catch(function (err) {
     if (err.code !== 'EEXIST') throw err;
 
-    var log = {
+    let log = {
       tmpl: 'pid file already exists at <%= path %>',
       path: path,
       pid: pid
@@ -36,7 +36,7 @@ module.exports = Promise.method(function (kbnServer, server, config) {
       pid: pid
     });
 
-    var clean = _.once(function (code) {
+    let clean = _.once(function (code) {
       unlink(path);
     });
 

src/server/plugins/scan.js

@@ -6,7 +6,7 @@ import { each } from 'bluebird';
 import PluginCollection from './plugin_collection';
 module.exports = async (kbnServer, server, config) => {
 
-  var plugins = kbnServer.plugins = new PluginCollection(kbnServer);
+  let plugins = kbnServer.plugins = new PluginCollection(kbnServer);
 
   let scanDirs = [].concat(config.get('plugins.scanDirs') || []);
   let pluginPaths = [].concat(config.get('plugins.paths') || []);

src/server/status/__tests__/server_status.js

@@ -17,21 +17,21 @@ describe('ServerStatus class', function () {
 
   describe('#create(name)', function () {
     it('should create a new status by name', function () {
-      var status = serverStatus.create('name');
+      let status = serverStatus.create('name');
       expect(status).to.be.a(Status);
     });
   });
 
   describe('#get(name)', function () {
     it('exposes plugins by name', function () {
-      var status = serverStatus.create('name');
+      let status = serverStatus.create('name');
       expect(serverStatus.get('name')).to.be(status);
     });
   });
 
   describe('#getState(name)', function () {
     it('should expose the state of the plugin by name', function () {
-      var status = serverStatus.create('name');
+      let status = serverStatus.create('name');
       status.green();
       expect(serverStatus.getState('name')).to.be('green');
     });
@@ -39,11 +39,11 @@ describe('ServerStatus class', function () {
 
   describe('#overall()', function () {
     it('considers each status to produce a summary', function () {
-      var status = serverStatus.create('name');
+      let status = serverStatus.create('name');
 
       expect(serverStatus.overall().state).to.be('uninitialized');
 
-      var match = function (overall, state) {
+      let match = function (overall, state) {
         expect(overall).to.have.property('state', state.id);
         expect(overall).to.have.property('title', state.title);
         expect(overall).to.have.property('icon', state.icon);
@@ -65,20 +65,20 @@ describe('ServerStatus class', function () {
 
   describe('#toJSON()', function () {
     it('serializes to overall status and individuals', function () {
-      var one = serverStatus.create('one');
-      var two = serverStatus.create('two');
-      var three = serverStatus.create('three');
+      let one = serverStatus.create('one');
+      let two = serverStatus.create('two');
+      let three = serverStatus.create('three');
 
       one.green();
       two.yellow();
       three.red();
 
-      var obj = JSON.parse(JSON.stringify(serverStatus));
+      let obj = JSON.parse(JSON.stringify(serverStatus));
       expect(obj).to.have.property('overall');
       expect(obj.overall.state).to.eql(serverStatus.overall().state);
       expect(obj.statuses).to.have.length(3);
 
-      var outs = _.indexBy(obj.statuses, 'name');
+      let outs = _.indexBy(obj.statuses, 'name');
       expect(outs.one).to.have.property('state', 'green');
       expect(outs.two).to.have.property('state', 'yellow');
       expect(outs.three).to.have.property('state', 'red');

src/server/status/__tests__/status.js

@@ -17,7 +17,7 @@ describe('Status class', function () {
   });
 
   it('emits change when the status is set', function (done) {
-    var status = serverStatus.create('test');
+    let status = serverStatus.create('test');
 
     status.once('change', function (prev, prevMsg) {
       expect(status.state).to.be('green');
@@ -40,8 +40,8 @@ describe('Status class', function () {
   });
 
   it('should only trigger the change listener when something changes', function () {
-    var status = serverStatus.create('test');
-    var stub = sinon.stub();
+    let status = serverStatus.create('test');
+    let stub = sinon.stub();
     status.on('change', stub);
     status.green('Ready');
     status.green('Ready');
@@ -50,17 +50,17 @@ describe('Status class', function () {
   });
 
   it('should create a JSON representation of the status', function () {
-    var status = serverStatus.create('test');
+    let status = serverStatus.create('test');
     status.green('Ready');
 
-    var json = status.toJSON();
+    let json = status.toJSON();
     expect(json.state).to.eql('green');
     expect(json.message).to.eql('Ready');
   });
 
   it('should call on handler if status is already matched', function (done) {
-    var status = serverStatus.create('test');
-    var msg = 'Test Ready';
+    let status = serverStatus.create('test');
+    let msg = 'Test Ready';
     status.green(msg);
 
     status.on('green', function (prev, prevMsg) {
@@ -73,8 +73,8 @@ describe('Status class', function () {
   });
 
   it('should call once handler if status is already matched', function (done) {
-    var status = serverStatus.create('test');
-    var msg = 'Test Ready';
+    let status = serverStatus.create('test');
+    let msg = 'Test Ready';
     status.green(msg);
 
     status.once('green', function (prev, prevMsg) {
@@ -88,16 +88,16 @@ describe('Status class', function () {
 
   function testState(color) {
     it(`should change the state to ${color} when #${color}() is called`, function () {
-      var status = serverStatus.create('test');
-      var message = 'testing ' + color;
+      let status = serverStatus.create('test');
+      let message = 'testing ' + color;
       status[color](message);
       expect(status).to.have.property('state', color);
       expect(status).to.have.property('message', message);
     });
 
     it(`should trigger the "change" listner when #${color}() is called`, function (done) {
-      var status = serverStatus.create('test');
-      var message = 'testing ' + color;
+      let status = serverStatus.create('test');
+      let message = 'testing ' + color;
       status.on('change', function (prev, prevMsg) {
         expect(status.state).to.be(color);
         expect(status.message).to.be(message);
@@ -110,8 +110,8 @@ describe('Status class', function () {
     });
 
     it(`should trigger the "${color}" listner when #${color}() is called`, function (done) {
-      var status = serverStatus.create('test');
-      var message = 'testing ' + color;
+      let status = serverStatus.create('test');
+      let message = 'testing ' + color;
       status.on(color, function (prev, prevMsg) {
         expect(status.state).to.be(color);
         expect(status.message).to.be(message);

src/server/status/index.js

@@ -22,8 +22,8 @@ module.exports = function (kbnServer, server, config) {
   });
 
   server.decorate('reply', 'renderStatusPage', function () {
-    var app = kbnServer.uiExports.getHiddenApp('status_page');
-    var resp = app ? this.renderApp(app) : this(kbnServer.status.toString());
+    let app = kbnServer.uiExports.getHiddenApp('status_page');
+    let resp = app ? this.renderApp(app) : this(kbnServer.status.toString());
     resp.code(kbnServer.status.isGreen() ? 200 : 503);
     return resp;
   });

src/server/status/metrics.js

@@ -10,7 +10,7 @@ module.exports = function (kbnServer, server, config) {
     let secSinceLast = (now - lastReport) / 1000;
     lastReport = now;
 
-    var port = config.get('server.port');
+    let port = config.get('server.port');
     let requests = _.get(event, ['requests', port, 'total'], 0);
     let requestsPerSecond = requests / secSinceLast;
 

src/server/status/samples.js

@@ -7,8 +7,8 @@ function Samples(max) {
 }
 
 Samples.prototype.add = function (sample) {
-  var vals = this.vals;
-  var length = this.length = Math.min(this.length + 1, this.max);
+  let vals = this.vals;
+  let length = this.length = Math.min(this.length + 1, this.max);
 
   _.forOwn(sample, function (val, name) {
     if (val == null) val = null;

src/server/status/server_status.js

@@ -31,15 +31,15 @@ module.exports = class ServerStatus {
   }
 
   overall() {
-    var state = _(this._created)
+    let state = _(this._created)
     .map(function (status) {
       return states.get(status.state);
     })
     .sortBy('severity')
     .pop();
 
-    var statuses = _.where(this._created, { state: state.id });
-    var since = _.get(_.sortBy(statuses, 'since'), [0, 'since']);
+    let statuses = _.where(this._created, { state: state.id });
+    let since = _.get(_.sortBy(statuses, 'since'), [0, 'since']);
 
     return {
       state: state.id,
@@ -59,7 +59,7 @@ module.exports = class ServerStatus {
   }
 
   toString() {
-    var overall = this.overall();
+    let overall = this.overall();
     return `${overall.title} – ${overall.nickname}`;
   }
 

src/server/status/status.js

@@ -13,7 +13,7 @@ class Status extends EventEmitter {
 
     this.on('change', function (previous, previousMsg) {
       this.since = new Date();
-      var tags = ['status', name];
+      let tags = ['status', name];
       tags.push(this.state === 'red' ? 'error' : 'info');
 
       server.log(tags, {

src/test_utils/no_digest_promises.js

@@ -8,7 +8,7 @@ Bluebird.longStackTraces();
  * replace the Promise service with Bluebird so that tests
  * can use promises without having to call $rootScope.apply()
  *
- * var noDigestPromises = require('test_utils/no_digest_promises');
+ * let noDigestPromises = require('test_utils/no_digest_promises');
  *
  * describe('some module that does complex shit with promises', function () {
  *   beforeEach(noDigestPromises.activate);
@@ -16,7 +16,7 @@ Bluebird.longStackTraces();
  * });
  */
 
-var active = false;
+let active = false;
 
 uiModules
 .get('kibana')

src/test_utils/simulate_keys.js

@@ -2,8 +2,8 @@ import $ from 'jquery';
 import _ from 'lodash';
 import Promise from 'bluebird';
 import keyMap from 'ui/utils/key_map';
-var reverseKeyMap = _.mapValues(_.invert(keyMap), _.ary(_.parseInt, 1));
-var KeyboardEvent = window.KeyboardEvent;
+let reverseKeyMap = _.mapValues(_.invert(keyMap), _.ary(_.parseInt, 1));
+let KeyboardEvent = window.KeyboardEvent;
 
 /**
  * Simulate keyboard events in an element. This allows testing the way that
@@ -35,7 +35,7 @@ var KeyboardEvent = window.KeyboardEvent;
  * @async
  */
 export default function ($el, sequence) {
-  var modifierState = {
+  let modifierState = {
     ctrlKey: false,
     shiftKey: false,
     altKey: false,
@@ -45,7 +45,7 @@ export default function ($el, sequence) {
   return doList(_.clone(sequence));
 
   function setModifier(key, state) {
-    var name = key + 'Key';
+    let name = key + 'Key';
     if (modifierState.hasOwnProperty(name)) {
       modifierState[name] = !!state;
     }
@@ -55,7 +55,7 @@ export default function ($el, sequence) {
     return Promise.try(function () {
       if (!list || !list.length) return;
 
-      var event = list[0];
+      let event = list[0];
       if (_.isString(event)) {
         event = { type: 'press', key: event };
       }
@@ -91,14 +91,14 @@ export default function ($el, sequence) {
   }
 
   function fire(type, key, repeat) {
-    var keyCode = reverseKeyMap[key];
+    let keyCode = reverseKeyMap[key];
     if (!keyCode) throw new TypeError('invalid key "' + key + '"');
 
     if (type === 'keydown') setModifier(key, true);
     if (type === 'keyup') setModifier(key, false);
 
-    var $target = _.isFunction($el) ? $el() : $el;
-    var $event = new $.Event(type, _.defaults({ keyCode: keyCode }, modifierState));
+    let $target = _.isFunction($el) ? $el() : $el;
+    let $event = new $.Event(type, _.defaults({ keyCode: keyCode }, modifierState));
     $target.trigger($event);
   }
 };

src/test_utils/stub_index_pattern.js

@@ -9,10 +9,10 @@ import RegistryFieldFormatsProvider from 'ui/registry/field_formats';
 import IndexPatternsFlattenHitProvider from 'ui/index_patterns/_flatten_hit';
 import IndexPatternsFieldProvider from 'ui/index_patterns/_field';
 export default function (Private) {
-  var fieldFormats = Private(RegistryFieldFormatsProvider);
-  var flattenHit = Private(IndexPatternsFlattenHitProvider);
+  let fieldFormats = Private(RegistryFieldFormatsProvider);
+  let flattenHit = Private(IndexPatternsFlattenHitProvider);
 
-  var Field = Private(IndexPatternsFieldProvider);
+  let Field = Private(IndexPatternsFieldProvider);
 
   function StubIndexPattern(pattern, timeField, fields) {
     this.id = pattern;

src/utils/package_json.js

@@ -5,7 +5,7 @@ let packageDir;
 let packagePath;
 
 while (!packagePath || !existsSync(packagePath)) {
-  var prev = packageDir;
+  let prev = packageDir;
   packageDir = prev ? join(prev, '..') : __dirname;
   packagePath = join(packageDir, 'package.json');