Add author token filtering support

Add ability to filter test cases with author
username.

ee/app/assets/javascripts/test_case_list/components/test_case_list_root.vue

 <script>
 import { GlButton } from '@gitlab/ui';
 
+import Api from '~/api';
 import { s__, __ } from '~/locale';
 import createFlash from '~/flash';
 import axios from '~/lib/utils/axios_utils';
@@ -8,6 +9,7 @@ import { urlParamsToObject } from '~/lib/utils/common_utils';
 import { updateHistory, setUrlParams } from '~/lib/utils/url_utility';
 
 import IssuableList from '~/issuable_list/components/issuable_list_root.vue';
+import AuthorToken from '~/vue_shared/components/filtered_search_bar/tokens/author_token.vue';
 import LabelToken from '~/vue_shared/components/filtered_search_bar/tokens/label_token.vue';
 
 import TestCaseListEmptyState from './test_case_list_empty_state.vue';
@@ -215,6 +217,17 @@ export default {
     },
     getFilteredSearchTokens() {
       return [
+        {
+          type: 'author_username',
+          icon: 'user',
+          title: __('Author'),
+          unique: true,
+          symbol: '@',
+          token: AuthorToken,
+          operators: [{ value: '=', description: __('is'), default: 'true' }],
+          fetchPath: this.projectFullPath,
+          fetchAuthors: Api.projectUsers.bind(Api),
+        },
         {
           type: 'label_name',
           icon: 'labels',

ee/app/assets/javascripts/test_case_list/queries/project_test_cases.query.graphql

@@ -6,6 +6,7 @@ query projectIssues(
   $projectPath: ID!
   $types: [IssueType!]
   $state: IssuableState
+  $authorUsername: String = ""
   $labelName: [String]
   $search: String = ""
   $sortBy: IssueSort = created_desc
@@ -19,6 +20,7 @@ query projectIssues(
     issues(
       types: $types
       state: $state
+      authorUsername: $authorUsername
       labelName: $labelName
       search: $search
       sort: $sortBy

ee/changelogs/unreleased/292721-test-case-author-filtering.yml

+---
+title: Add author token filtering support for Test Cases
+merge_request: 50747
+author:
+type: added

ee/spec/features/projects/quality/test_case_list_spec.rb

@@ -55,6 +55,16 @@ RSpec.describe 'Test Cases', :js do
       end
     end
 
+    it 'shows filter tokens author and label' do
+      page.within('.vue-filtered-search-bar-container .gl-search-box-by-click') do
+        page.find('input').click
+
+        expect(page.find('.gl-filtered-search-suggestion-list')).to have_selector('li', count: 2)
+        expect(page.find('.gl-filtered-search-suggestion-list li:nth-child(1)')).to have_content('Author')
+        expect(page.find('.gl-filtered-search-suggestion-list li:nth-child(2)')).to have_content('Label')
+      end
+    end
+
     context 'open tab' do
       it 'shows list of all open test cases' do
         page.within('.issuable-list-container .issuable-list') do