Backport PR #6653

---------

**Commit 1:**
[internal] Replace empty var declaration with let

Any time there is a variable defined in a JS file without also storing a
value in it, we know that definition cannot be converted to a const, so
we convert it to a let.

For example:

`var blah;` becomes `let blah;`

Some of these things variables might be unused, and many others can
likely be switched to const with only minor refactoring, but the commit
is very large, so there are no changes in it other than the 1:1 switch.

* Original sha: bfc59e9
* Authored by Court Ewing <court@epixa.com> on 2016-03-24T22:27:29Z

backport.rej.md

@@ -0,0 +1,24 @@
+Backport of PR [#6653](https://github.com/elastic/kibana/pull/6653) to branch 4.x failed
+
+60 file could not be found in this branch,
+182 patch failed to apply,
+while 30 patch applied successfully.
+
+The following script will rebase the commits that need to be backported onto
+this backport branch. Resolve any conflicts as you normally would in a rebase.
+You do *not* need to remove these backport.rej files, and you can add
+additional commits if that's necessary.
+
+```
+sh begin-backport.rej
+```
+
+Once the conficts are resolved on your local backport branch, the following
+script will remove the remnants of this backport commit and squash the newly
+resolved commits (and any others you may have added) into a single backport
+commit with the proper commit message. Finally, it'll replace the upstream
+backport branch (the one from the backport PR) with the result.
+
+```
+sh finish-backport.rej
+```

src/server/status/__tests__/status.js.rej

@@ -0,0 +1,12 @@
+diff a/src/server/status/__tests__/status.js b/src/server/status/__tests__/status.js	(rejected hunks)
+@@ -4,8 +4,8 @@ import Status from '../status';
+ import ServerStatus from '../server_status';
+
+ describe('Status class', function () {
+-  var server;
+-  var serverStatus;
++  let server;
++  let serverStatus;
+
+   beforeEach(function () {
+     server = { expose: sinon.stub(), log: sinon.stub() };

src/ui/public/Binder/__tests__/binder.js.rej

@@ -0,0 +1,10 @@
+diff a/src/ui/public/binder/__tests__/binder.js b/src/ui/public/binder/__tests__/binder.js	(rejected hunks)
+@@ -6,7 +6,7 @@ import Binder from 'ui/binder';
+ import $ from 'jquery';
+
+ describe('Binder class', function () {
+-  var $scope;
++  let $scope;
+
+   beforeEach(ngMock.module('kibana'));
+   beforeEach(ngMock.inject(function ($rootScope) {

src/ui/public/Vis/__tests__/_renderbot.js.rej

@@ -0,0 +1,10 @@
+diff a/src/ui/public/vis/__tests__/_renderbot.js b/src/ui/public/vis/__tests__/_renderbot.js	(rejected hunks)
+@@ -2,7 +2,7 @@ import expect from 'expect.js';
+ import ngMock from 'ng_mock';
+ import VisRenderbotProvider from 'ui/vis/renderbot';
+ describe('renderbot', function () {
+-  var Renderbot;
++  let Renderbot;
+
+   function init() {
+     ngMock.module('kibana');

src/ui/public/Vis/__tests__/_vis.js.rej

@@ -0,0 +1,17 @@
+diff a/src/ui/public/vis/__tests__/_vis.js b/src/ui/public/vis/__tests__/_vis.js	(rejected hunks)
+@@ -7,11 +7,11 @@ import RegistryVisTypesProvider from 'ui/registry/vis_types';
+ describe('Vis Class', function () {
+
+
+-  var indexPattern;
+-  var Vis;
+-  var visTypes;
++  let indexPattern;
++  let Vis;
++  let visTypes;
+
+-  var vis;
++  let vis;
+   var stateFixture = {
+     type: 'pie',
+     aggs: [

src/ui/public/agg_response/geo_json/__tests__/geo_json.js.rej

@@ -0,0 +1,18 @@
+diff a/src/ui/public/agg_response/geo_json/__tests__/geo_json.js b/src/ui/public/agg_response/geo_json/__tests__/geo_json.js	(rejected hunks)
+@@ -9,11 +9,11 @@ import AggResponseTabifyTabifyProvider from 'ui/agg_response/tabify/tabify';
+ import AggResponseGeoJsonGeoJsonProvider from 'ui/agg_response/geo_json/geo_json';
+
+ describe('GeoJson Agg Response Converter', function () {
+-  var vis;
+-  var tabify;
+-  var convert;
+-  var esResponse;
+-  var aggs;
++  let vis;
++  let tabify;
++  let convert;
++  let esResponse;
++  let aggs;
+
+   beforeEach(ngMock.module('kibana'));
+   beforeEach(ngMock.inject(function (Private) {

src/ui/public/agg_response/hierarchical/__tests__/build_hierarchical_data.js.rej

@@ -0,0 +1,18 @@
+diff a/src/ui/public/agg_response/hierarchical/__tests__/build_hierarchical_data.js b/src/ui/public/agg_response/hierarchical/__tests__/build_hierarchical_data.js	(rejected hunks)
+@@ -9,11 +9,11 @@ import VisAggConfigsProvider from 'ui/vis/agg_configs';
+ import FixturesStubbedLogstashIndexPatternProvider from 'fixtures/stubbed_logstash_index_pattern';
+ import AggResponseHierarchicalBuildHierarchicalDataProvider from 'ui/agg_response/hierarchical/build_hierarchical_data';
+
+-var Vis;
+-var Notifier;
+-var AggConfigs;
+-var indexPattern;
+-var buildHierarchicalData;
++let Vis;
++let Notifier;
++let AggConfigs;
++let indexPattern;
++let buildHierarchicalData;
+
+ describe('buildHierarchicalData', function () {
+

src/ui/public/agg_response/hierarchical/__tests__/collect_branch.js.rej

@@ -0,0 +1,10 @@
+diff a/src/ui/public/agg_response/hierarchical/__tests__/collect_branch.js b/src/ui/public/agg_response/hierarchical/__tests__/collect_branch.js	(rejected hunks)
+@@ -3,7 +3,7 @@ import _ from 'lodash';
+ import collectBranch from 'ui/agg_response/hierarchical/_collect_branch';
+ import expect from 'expect.js';
+ describe('collectBranch()', function () {
+-  var results;
++  let results;
+   var convert = function (name) {
+     return 'converted:' + name;
+   };

src/ui/public/agg_response/hierarchical/__tests__/create_raw_data.js.rej

@@ -0,0 +1,21 @@
+diff a/src/ui/public/agg_response/hierarchical/__tests__/create_raw_data.js b/src/ui/public/agg_response/hierarchical/__tests__/create_raw_data.js	(rejected hunks)
+@@ -9,14 +9,14 @@ import VisProvider from 'ui/vis';
+ import VisAggConfigsProvider from 'ui/vis/agg_configs';
+ import FixturesStubbedLogstashIndexPatternProvider from 'fixtures/stubbed_logstash_index_pattern';
+
+-var AggConfigs;
+-var Vis;
+-var indexPattern;
++let AggConfigs;
++let Vis;
++let indexPattern;
+
+ describe('buildHierarchicalData()', function () {
+   describe('createRawData()', function () {
+-    var vis;
+-    var results;
++    let vis;
++    let results;
+
+     beforeEach(ngMock.module('kibana'));
+

src/ui/public/agg_response/hierarchical/__tests__/transform_aggregation.js.rej

@@ -0,0 +1,12 @@
+diff a/src/ui/public/agg_response/hierarchical/__tests__/transform_aggregation.js b/src/ui/public/agg_response/hierarchical/__tests__/transform_aggregation.js	(rejected hunks)
+@@ -5,8 +5,8 @@ import AggResponseHierarchicalTransformAggregationProvider from 'ui/agg_response
+
+ describe('buildHierarchicalData()', function () {
+   describe('transformAggregation()', function () {
+-    var transform;
+-    var fixture;
++    let transform;
++    let fixture;
+
+     beforeEach(ngMock.module('kibana'));
+     beforeEach(ngMock.inject(function (Private) {

src/ui/public/agg_response/hierarchical/_array_to_linked_list.js.rej

@@ -0,0 +1,9 @@
+diff a/src/ui/public/agg_response/hierarchical/_array_to_linked_list.js b/src/ui/public/agg_response/hierarchical/_array_to_linked_list.js	(rejected hunks)
+@@ -1,6 +1,6 @@
+ import _ from 'lodash';
+ export default function (buckets) {
+-  var previous;
++  let previous;
+   _.each(buckets, function (bucket) {
+     if (previous) {
+       bucket._previous = previous;

src/ui/public/agg_response/hierarchical/_hierarchical_tooltip_formatter.js.rej

@@ -0,0 +1,10 @@
+diff a/src/ui/public/agg_response/hierarchical/_hierarchical_tooltip_formatter.js b/src/ui/public/agg_response/hierarchical/_hierarchical_tooltip_formatter.js	(rejected hunks)
+@@ -21,7 +21,7 @@ export default function HierarchicalTooltipFormaterProvider($rootScope, $compile
+       _.forEachRight($tooltipScope.rows, function (row, i, rows) {
+         row.spacer = $sce.trustAsHtml(_.repeat(' ', row.depth));
+
+-        var percent;
++        let percent;
+         if (row.item.percentOfGroup != null) {
+           percent = row.item.percentOfGroup;
+         }

src/ui/public/agg_response/point_series/__tests__/_add_to_siri.js.rej

@@ -0,0 +1,10 @@
+diff a/src/ui/public/agg_response/point_series/__tests__/_add_to_siri.js b/src/ui/public/agg_response/point_series/__tests__/_add_to_siri.js	(rejected hunks)
+@@ -2,7 +2,7 @@ import expect from 'expect.js';
+ import ngMock from 'ng_mock';
+ import AggResponsePointSeriesAddToSiriProvider from 'ui/agg_response/point_series/_add_to_siri';
+ describe('addToSiri', function () {
+-  var addToSiri;
++  let addToSiri;
+
+   beforeEach(ngMock.module('kibana'));
+   beforeEach(ngMock.inject(function (Private) {

src/ui/public/agg_response/point_series/__tests__/_fake_x_aspect.js.rej

@@ -0,0 +1,18 @@
+diff a/src/ui/public/agg_response/point_series/__tests__/_fake_x_aspect.js b/src/ui/public/agg_response/point_series/__tests__/_fake_x_aspect.js	(rejected hunks)
+@@ -6,11 +6,11 @@ import AggTypesAggTypeProvider from 'ui/agg_types/agg_type';
+ import AggResponsePointSeriesFakeXAspectProvider from 'ui/agg_response/point_series/_fake_x_aspect';
+ describe('makeFakeXAspect', function () {
+
+-  var makeFakeXAspect;
+-  var Vis;
+-  var AggType;
+-  var AggConfig;
+-  var indexPattern;
++  let makeFakeXAspect;
++  let Vis;
++  let AggType;
++  let AggConfig;
++  let indexPattern;
+
+   beforeEach(ngMock.module('kibana'));
+   beforeEach(ngMock.inject(function (Private) {

src/ui/public/agg_response/point_series/__tests__/_get_aspects.js.rej

@@ -0,0 +1,29 @@
+diff a/src/ui/public/agg_response/point_series/__tests__/_get_aspects.js b/src/ui/public/agg_response/point_series/__tests__/_get_aspects.js	(rejected hunks)
+@@ -9,11 +9,11 @@ import AggResponsePointSeriesGetAspectsProvider from 'ui/agg_response/point_seri
+ import FixturesStubbedLogstashIndexPatternProvider from 'fixtures/stubbed_logstash_index_pattern';
+ describe('getAspects', function () {
+
+-  var Vis;
+-  var Table;
+-  var AggConfig;
+-  var indexPattern;
+-  var getAspects;
++  let Vis;
++  let Table;
++  let AggConfig;
++  let indexPattern;
++  let getAspects;
+
+   beforeEach(ngMock.module('kibana'));
+   beforeEach(ngMock.inject(function (Private) {
+@@ -24,8 +24,8 @@ describe('getAspects', function () {
+     indexPattern = Private(FixturesStubbedLogstashIndexPatternProvider);
+   }));
+
+-  var vis;
+-  var table;
++  let vis;
++  let table;
+
+   var date = _.memoize(function (n) {
+     return moment().startOf('day').add(n, 'hour').valueOf();

src/ui/public/agg_response/point_series/__tests__/_get_point.js.rej

@@ -0,0 +1,10 @@
+diff a/src/ui/public/agg_response/point_series/__tests__/_get_point.js b/src/ui/public/agg_response/point_series/__tests__/_get_point.js	(rejected hunks)
+@@ -5,7 +5,7 @@ import AggResponsePointSeriesGetPointProvider from 'ui/agg_response/point_series
+
+ describe('getPoint', function () {
+
+-  var getPoint;
++  let getPoint;
+
+   var truthFormatted = { fieldFormatter: _.constant(_.constant(true)) };
+   var identFormatted = { fieldFormatter: _.constant(_.identity) };

src/ui/public/agg_response/point_series/__tests__/_get_series.js.rej

@@ -0,0 +1,10 @@
+diff a/src/ui/public/agg_response/point_series/__tests__/_get_series.js b/src/ui/public/agg_response/point_series/__tests__/_get_series.js	(rejected hunks)
+@@ -3,7 +3,7 @@ import expect from 'expect.js';
+ import ngMock from 'ng_mock';
+ import AggResponsePointSeriesGetSeriesProvider from 'ui/agg_response/point_series/_get_series';
+ describe('getSeries', function () {
+-  var getSeries;
++  let getSeries;
+
+   var agg = { fieldFormatter: _.constant(_.identity) };
+

src/ui/public/agg_response/point_series/__tests__/_init_x_axis.js.rej

@@ -0,0 +1,10 @@
+diff a/src/ui/public/agg_response/point_series/__tests__/_init_x_axis.js b/src/ui/public/agg_response/point_series/__tests__/_init_x_axis.js	(rejected hunks)
+@@ -4,7 +4,7 @@ import ngMock from 'ng_mock';
+ import AggResponsePointSeriesInitXAxisProvider from 'ui/agg_response/point_series/_init_x_axis';
+ describe('initXAxis', function () {
+
+-  var initXAxis;
++  let initXAxis;
+
+   beforeEach(ngMock.module('kibana'));
+   beforeEach(ngMock.inject(function (Private) {

src/ui/public/agg_response/point_series/__tests__/_init_y_axis.js.rej

@@ -0,0 +1,10 @@
+diff a/src/ui/public/agg_response/point_series/__tests__/_init_y_axis.js b/src/ui/public/agg_response/point_series/__tests__/_init_y_axis.js	(rejected hunks)
+@@ -4,7 +4,7 @@ import ngMock from 'ng_mock';
+ import AggResponsePointSeriesInitYAxisProvider from 'ui/agg_response/point_series/_init_y_axis';
+ describe('initYAxis', function () {
+
+-  var initYAxis;
++  let initYAxis;
+
+   beforeEach(ngMock.module('kibana'));
+   beforeEach(ngMock.inject(function (Private) {

src/ui/public/agg_response/point_series/__tests__/_main.js.rej

@@ -0,0 +1,16 @@
+diff a/src/ui/public/agg_response/point_series/__tests__/_main.js b/src/ui/public/agg_response/point_series/__tests__/_main.js	(rejected hunks)
+@@ -11,10 +11,10 @@ describe('pointSeriesChartDataFromTable', function () {
+   this.slow(1000);
+
+
+-  var pointSeriesChartDataFromTable;
+-  var indexPattern;
+-  var Table;
+-  var Vis;
++  let pointSeriesChartDataFromTable;
++  let indexPattern;
++  let Table;
++  let Vis;
+
+   beforeEach(ngMock.module('kibana'));
+   beforeEach(ngMock.inject(function (Private) {

src/ui/public/agg_response/point_series/__tests__/_tooltip_formatter.js.rej

@@ -0,0 +1,10 @@
+diff a/src/ui/public/agg_response/point_series/__tests__/_tooltip_formatter.js b/src/ui/public/agg_response/point_series/__tests__/_tooltip_formatter.js	(rejected hunks)
+@@ -5,7 +5,7 @@ import ngMock from 'ng_mock';
+ import AggResponsePointSeriesTooltipFormatterProvider from 'ui/agg_response/point_series/_tooltip_formatter';
+ describe('tooltipFormatter', function () {
+
+-  var tooltipFormatter;
++  let tooltipFormatter;
+
+   beforeEach(ngMock.module('kibana'));
+   beforeEach(ngMock.inject(function (Private) {

src/ui/public/agg_response/point_series/_get_series.js.rej

@@ -0,0 +1,10 @@
+diff a/src/ui/public/agg_response/point_series/_get_series.js b/src/ui/public/agg_response/point_series/_get_series.js	(rejected hunks)
+@@ -37,7 +37,7 @@ export default function PointSeriesGetSeries(Private) {
+     if (multiY) {
+       series = _.sortBy(series, function (siri) {
+         var firstVal = siri.values[0];
+-        var y;
++        let y;
+
+         if (firstVal) {
+           var agg = firstVal.aggConfigResult.aggConfig;

src/ui/public/agg_response/tabify/__tests__/_buckets.js.rej

@@ -0,0 +1,10 @@
+diff a/src/ui/public/agg_response/tabify/__tests__/_buckets.js b/src/ui/public/agg_response/tabify/__tests__/_buckets.js	(rejected hunks)
+@@ -2,7 +2,7 @@ import expect from 'expect.js';
+ import ngMock from 'ng_mock';
+ import AggResponseTabifyBucketsProvider from 'ui/agg_response/tabify/_buckets';
+ describe('Buckets wrapper', function () {
+-  var Buckets;
++  let Buckets;
+
+   beforeEach(ngMock.module('kibana'));
+   beforeEach(ngMock.inject(function (Private, $injector) {

src/ui/public/agg_response/tabify/__tests__/_get_columns.js.rej

@@ -0,0 +1,14 @@
+diff a/src/ui/public/agg_response/tabify/__tests__/_get_columns.js b/src/ui/public/agg_response/tabify/__tests__/_get_columns.js	(rejected hunks)
+@@ -4,9 +4,9 @@ import AggResponseTabifyGetColumnsProvider from 'ui/agg_response/tabify/_get_col
+ import VisProvider from 'ui/vis';
+ import FixturesStubbedLogstashIndexPatternProvider from 'fixtures/stubbed_logstash_index_pattern';
+ describe('get columns', function () {
+-  var getColumns;
+-  var Vis;
+-  var indexPattern;
++  let getColumns;
++  let Vis;
++  let indexPattern;
+
+   beforeEach(ngMock.module('kibana'));
+   beforeEach(ngMock.inject(function (Private, $injector) {

src/ui/public/agg_response/tabify/__tests__/_integration.js.rej

@@ -0,0 +1,16 @@
+diff a/src/ui/public/agg_response/tabify/__tests__/_integration.js b/src/ui/public/agg_response/tabify/__tests__/_integration.js	(rejected hunks)
+@@ -7,10 +7,10 @@ import VisProvider from 'ui/vis';
+ import FixturesStubbedLogstashIndexPatternProvider from 'fixtures/stubbed_logstash_index_pattern';
+ describe('tabifyAggResponse Integration', function () {
+
+-  var Vis;
+-  var Buckets;
+-  var indexPattern;
+-  var tabifyAggResponse;
++  let Vis;
++  let Buckets;
++  let indexPattern;
++  let tabifyAggResponse;
+
+   beforeEach(ngMock.module('kibana'));
+   beforeEach(ngMock.inject(function (Private, $injector) {

src/ui/public/agg_response/tabify/__tests__/_response_writer.js.rej

@@ -0,0 +1,24 @@
+diff a/src/ui/public/agg_response/tabify/__tests__/_response_writer.js b/src/ui/public/agg_response/tabify/__tests__/_response_writer.js	(rejected hunks)
+@@ -10,14 +10,14 @@ import VisProvider from 'ui/vis';
+ import FixturesStubbedLogstashIndexPatternProvider from 'fixtures/stubbed_logstash_index_pattern';
+ describe('ResponseWriter class', function () {
+
+-  var Vis;
+-  var Table;
+-  var Buckets;
+-  var Private;
+-  var TableGroup;
+-  var getColumns;
+-  var indexPattern;
+-  var ResponseWriter;
++  let Vis;
++  let Table;
++  let Buckets;
++  let Private;
++  let TableGroup;
++  let getColumns;
++  let indexPattern;
++  let ResponseWriter;
+
+   function defineSetup(stubGetColumns) {
+     beforeEach(ngMock.module('kibana'));