Hide behind feature flag

Add reviewer_approval_rules FF

app/assets/javascripts/users_select/index.js

@@ -831,7 +831,7 @@ UsersSelect.prototype.renderRowAvatar = function(issuableType, user, img) {
 };
 
 UsersSelect.prototype.renderApprovalRules = function(elsClassName, approvalRules = []) {
-  if (!elsClassName?.includes('reviewer')) {
+  if (!gon.features?.reviewerApprovalRules || !elsClassName?.includes('reviewer')) {
     return '';
   }
   const count = approvalRules.length;

app/controllers/projects/merge_requests/creations_controller.rb

@@ -14,6 +14,7 @@ class Projects::MergeRequests::CreationsController < Projects::MergeRequests::Ap
   before_action do
     push_frontend_feature_flag(:merge_request_reviewers, @project)
     push_frontend_feature_flag(:mr_collapsed_approval_rules, @project)
+    push_frontend_feature_flag(:reviewer_approval_rules, @project)
   end
 
   def new

app/controllers/projects/merge_requests_controller.rb

@@ -53,6 +53,7 @@ class Projects::MergeRequestsController < Projects::MergeRequests::ApplicationCo
     push_frontend_feature_flag(:vue_issuable_sidebar, @project.group)
     push_frontend_feature_flag(:merge_request_reviewers, @project)
     push_frontend_feature_flag(:mr_collapsed_approval_rules, @project)
+    push_frontend_feature_flag(:reviewer_approval_rules, @project)
   end
 
   around_action :allow_gitaly_ref_name_caching, only: [:index, :show, :discussions]

config/feature_flags/development/reviewer_approval_rules.yml

+---
+name: reviewer_approval_rules
+introduced_by_url: https://gitlab.com/gitlab-org/gitlab/-/merge_requests/46738
+rollout_issue_url: https://gitlab.com/gitlab-org/gitlab/-/issues/293742
+milestone: '13.7'
+type: development
+group: group::code review
+default_enabled: false

ee/spec/features/merge_request/user_edits_multiple_reviewers_mr_spec.rb

@@ -13,7 +13,6 @@ RSpec.describe 'Merge request > User edits MR with multiple reviewers' do
 
   context 'user approval rules', :js do
     let(:rule_name) { 'some-custom-rule' }
-    let(:user) { create(:admin) }
     let!(:mr_rule) { create(:approval_merge_request_rule, merge_request: merge_request, users: [user], name: rule_name, approvals_required: 1 )}
 
     it 'is not shown in assignee dropdown' do
@@ -34,4 +33,22 @@ RSpec.describe 'Merge request > User edits MR with multiple reviewers' do
       end
     end
   end
+
+  context 'when reviewer_approval_rules feature flag off' do
+    let(:rule_name) { 'some-custom-rule' }
+    let!(:mr_rule) { create(:approval_merge_request_rule, merge_request: merge_request, users: [user], name: rule_name, approvals_required: 1 )}
+
+    before do
+      stub_feature_flags(reviewer_approval_rules: false)
+    end
+
+    it 'is not shown in reviewer dropdown' do
+      find('.js-reviewer-search').click
+      wait_for_requests
+
+      page.within '.dropdown-menu-reviewer' do
+        expect(page).not_to have_content(rule_name)
+      end
+    end
+  end
 end