Fetch from all parent groups in issue epic select

The epic dropdown for issues should fetch epics from
all ancestor groups, not just the immediate parent.

Changelog: fixed
MR: https://gitlab.com/gitlab-org/gitlab/-/merge_requests/63618
EE: true

ee/app/assets/javascripts/sidebar/queries/group_epics.query.graphql

@@ -2,7 +2,12 @@
 
 query issueEpics($fullPath: ID!, $title: String, $state: EpicState) {
   workspace: group(fullPath: $fullPath) {
-    attributes: epics(search: $title, state: $state) {
+    attributes: epics(
+      search: $title
+      state: $state
+      includeAncestorGroups: true
+      includeDescendantGroups: false
+    ) {
       nodes {
         ...EpicFragment
         state

ee/spec/features/issues/epic_in_issue_sidebar_spec.rb

@@ -5,59 +5,73 @@ require 'spec_helper'
 RSpec.describe 'Epic in issue sidebar', :js do
   let_it_be(:user) { create(:user) }
   let_it_be(:group) { create(:group, :public) }
-  let_it_be(:epic1) { create(:epic, group: group, title: 'Foo') }
-  let_it_be(:epic2) { create(:epic, group: group, title: 'Bar') }
-  let_it_be(:epic3) { create(:epic, group: group, title: 'Baz') }
+  let_it_be(:epic1) { create(:epic, group: group, title: 'Epic Foo') }
+  let_it_be(:epic2) { create(:epic, group: group, title: 'Epic Bar') }
+  let_it_be(:epic3) { create(:epic, group: group, title: 'Epic Baz') }
   let_it_be(:project) { create(:project, :public, group: group) }
   let_it_be(:issue) { create(:issue, project: project) }
   let_it_be(:epic_issue) { create(:epic_issue, epic: epic1, issue: issue) }
 
+  let_it_be(:subgroup) { create(:group, :public, parent: group) }
+  let_it_be(:subproject) { create(:project, :public, group: subgroup) }
+  let_it_be(:subepic) { create(:epic, group: subgroup, title: 'Subgroup epic') }
+  let_it_be(:subissue) { create(:issue, project: subproject) }
+
+  let_it_be(:sidebar_epic_selector) { '[data-testid="sidebar-epic"]' }
+
   shared_examples 'epic in issue sidebar' do
+    before do
+      group.add_owner(user)
+      sign_in user
+    end
+
     context 'projects within a group' do
       before do
-        group.add_owner(user)
-        sign_in user
         visit project_issue_path(project, issue)
         wait_for_all_requests
       end
 
       it 'shows epic in issue sidebar' do
-        expect(page.find('[data-testid="sidebar-epic"]')).to have_content(epic1.title)
+        expect(page.find(sidebar_epic_selector)).to have_content(epic1.title)
       end
 
       it 'shows edit button in issue sidebar' do
-        expect(page.find('[data-testid="sidebar-epic"]')).to have_button('Edit')
+        expect(page.find(sidebar_epic_selector)).to have_button('Edit')
       end
 
       it 'shows epics select dropdown' do
-        page.within(find('[data-testid="sidebar-epic"]')) do
-          click_button 'Edit'
-
-          wait_for_all_requests
-
-          expect(page).to have_selector('.gl-new-dropdown-contents .gl-new-dropdown-item', count: 4) # `No Epic` + 3 epics
+        page.within(sidebar_epic_selector) do
+          click_edit
+
+          aggregate_failures do
+            expect(page).to have_selector('.gl-new-dropdown-contents .gl-new-dropdown-item', count: 4)
+            expect(page).to have_content 'No epic'
+            expect(page).to have_content epic1.title
+            expect(page).to have_content epic2.title
+            expect(page).to have_content epic3.title
+          end
         end
       end
 
       it 'supports searching for an epic' do
-        page.within(find('[data-testid="sidebar-epic"]')) do
-          click_button 'Edit'
-
-          wait_for_all_requests
+        page.within(sidebar_epic_selector) do
+          click_edit
 
           page.find('.gl-form-input').send_keys('Foo')
 
           wait_for_all_requests
 
-          expect(page).to have_selector('.gl-new-dropdown-contents .gl-new-dropdown-item', count: 2) # `No Epic` + 1 matching epic
+          aggregate_failures do
+            expect(page).to have_selector('.gl-new-dropdown-contents .gl-new-dropdown-item', count: 2)
+            expect(page).to have_content 'No epic'
+            expect(page).to have_content epic1.title
+          end
         end
       end
 
       it 'select an epic from the dropdown' do
-        page.within(find('[data-testid="sidebar-epic"]')) do
-          click_button 'Edit'
-
-          wait_for_all_requests
+        page.within(sidebar_epic_selector) do
+          click_edit
 
           find('.gl-new-dropdown-item', text: epic2.title).click
 
@@ -68,6 +82,28 @@ RSpec.describe 'Epic in issue sidebar', :js do
       end
     end
 
+    context 'project within a subgroup' do
+      before do
+        visit project_issue_path(subproject, issue)
+        wait_for_all_requests
+      end
+
+      it 'shows all epics belonging to the sub group and its parents' do
+        page.within(sidebar_epic_selector) do
+          click_edit
+
+          aggregate_failures do
+            expect(page).to have_selector('.gl-new-dropdown-contents .gl-new-dropdown-item', count: 5)
+            expect(page).to have_content 'No epic'
+            expect(page).to have_content epic1.title
+            expect(page).to have_content epic2.title
+            expect(page).to have_content epic3.title
+            expect(page).to have_content subepic.title
+          end
+        end
+      end
+    end
+
     context 'personal projects' do
       it 'does not show epic in issue sidebar' do
         personal_project = create(:project, :public)
@@ -127,4 +163,10 @@ RSpec.describe 'Epic in issue sidebar', :js do
   def expect_no_epic
     expect(page).not_to have_selector('.block.epic')
   end
+
+  def click_edit
+    click_button 'Edit'
+
+    wait_for_all_requests
+  end
 end