feat(VSelect): emit selected listIndex event (#7828)

* docs(component): menuListIndex event added to docs

Add update:menuListIndex event to VSelect documentation in events tab

* feat(VSelect): add update:listIndex event to VSelect

update:listIndex added to VSelect to indicate when keyboard-selected item is changed

* chore(deps): bump lodash.template from 4.4.0 to 4.5.0 (#7808)

Bumps [lodash.template](https://github.com/lodash/lodash) from 4.4.0 to 4.5.0.
- [Release notes](https://github.com/lodash/lodash/releases)
- [Commits](lodash/lodash@4.4.0...4.5.0)

Signed-off-by: dependabot[bot] <support@github.com>

* chore(release): publish v2.0.0-beta.8

* docs(vue-analytics): revert autoTracking parameter

* feat(VSelect): code review updates, name unification

Unified naming in docs to use kebab-case, moved tests to VSelect dir

* feat(VSelect): event name update:listIndex -> update:list-index

Changed event name to kebab case as in vue guide

packages/api-generator/src/helpers/variables.js

@@ -237,6 +237,10 @@ const VSelect = {
       name: 'update:search-input',
       value: 'string',
     },
+    {
+      name: 'update:list-index',
+      value: 'number',
+    },
     ...inputEvents,
     ...textEvents,
   ].concat(validatableEvents),

packages/docs/src/lang/en/components/Autocompletes.json

@@ -60,6 +60,7 @@
     "click:prepend": "Components.Inputs.events['click:prepend']",
     "click:prepend-inner": "Components.TextFields.events['click:prepend-inner']",
     "update:error": "Mixins.Validatable.events['update:error']",
+    "update:list-index": "Components.Selects.events['update:list-index']",
     "update:search-input": "The `search-input.sync` event"
   }
 }

packages/docs/src/lang/en/components/Combobox.json

@@ -42,6 +42,7 @@
     "click:prepend": "Components.Inputs.events['click:prepend']",
     "click:prepend-inner": "Components.TextFields.events['click:prepend-inner']",
     "update:error": "Mixins.Validatable.events['update:error']",
+    "update:list-index": "Components.Selects.events['update:list-index']",
     "update:search-input": "The `search-input.sync` event"
   }
 }

packages/docs/src/lang/en/components/Selects.json

@@ -100,6 +100,7 @@
     "click:prepend-inner": "Components.TextFields.events['click:prepend-inner']",
     "focus": "Emitted when component is focused",
     "update:error": "Mixins.Validatable.events['update:error']",
+    "update:list-index": "Emitted when menu item is selected using keyboard arrows",
     "update:search-input": "The `search-input.sync` event"
   }
 }

packages/vuetify/src/components/VSelect/VSelect.ts

@@ -609,6 +609,7 @@ export default baseMixins.extend<options>().extend({
       // listIndex change from menu
       if (this.isMenuActive && keyCode !== keyCodes.tab) {
         menu.changeListIndex(e)
+        this.$emit('update:list-index', menu.listIndex)
       }
 
       // If menu is not active, up and down can do

packages/vuetify/src/components/VSelect/__tests__/VSelect4.spec.ts

@@ -254,6 +254,26 @@ describe('VSelect.ts', () => {
     expect(wrapper.vm.$refs.menu.listIndex).toBe(-1)
   })
 
+  it('should emit listIndex event when navigated by keyboard', () => {
+    const wrapper = mountFunction({
+      propsData: {
+        items: ['foo', 'bar'],
+      },
+    })
+
+    const listIndexUpdate = jest.fn()
+    wrapper.vm.$on('update:list-index', listIndexUpdate)
+
+    const input = wrapper.find('input')
+    const slot = wrapper.find('.v-input__slot')
+    slot.trigger('click')
+
+    input.trigger('keydown.down')
+    expect(listIndexUpdate).toHaveBeenCalledWith(0)
+    input.trigger('keydown.down')
+    expect(listIndexUpdate).toHaveBeenCalledWith(1)
+  })
+
   it('should not change value when typing on readonly field', async () => {
     const wrapper = mountFunction({
       propsData: {