Namespace#self_and_hierarchy linear query

Integrates linear queries for both descendants and ancestors.

app/models/namespaces/traversal/linear.rb

@@ -57,6 +57,13 @@ module Namespaces
         traversal_ids.present?
       end
 
+      def use_traversal_ids_for_self_and_hierarchy?
+        return false unless use_traversal_ids?
+        return false unless Feature.enabled?(:use_traversal_ids_for_self_and_hierarchy, root_ancestor, default_enabled: :yaml)
+
+        traversal_ids.present?
+      end
+
       def use_traversal_ids_for_ancestors?
         return false unless use_traversal_ids?
         return false unless Feature.enabled?(:use_traversal_ids_for_ancestors, root_ancestor, default_enabled: :yaml)
@@ -107,6 +114,12 @@ module Namespaces
         self_and_descendants.where.not(id: id)
       end
 
+      def self_and_hierarchy
+        return super unless use_traversal_ids_for_self_and_hierarchy?
+
+        self_and_descendants.or(ancestors)
+      end
+
       def ancestors(hierarchy_order: nil)
         return super unless use_traversal_ids_for_ancestors?
 

config/feature_flags/development/use_traversal_ids_for_self_and_hierarchy.yml

+---
+name: use_traversal_ids_for_self_and_hierarchy
+introduced_by_url: https://gitlab.com/gitlab-org/gitlab/-/merge_requests/76814
+rollout_issue_url: https://gitlab.com/gitlab-org/gitlab/-/issues/348527
+milestone: '14.7'
+type: development
+group: group::workspace
+default_enabled: false

spec/models/group_spec.rb

@@ -502,6 +502,10 @@ RSpec.describe Group do
         it { expect(group.descendants.to_sql).not_to include 'traversal_ids @>' }
       end
 
+      describe '#self_and_hierarchy' do
+        it { expect(group.self_and_hierarchy.to_sql).not_to include 'traversal_ids @>' }
+      end
+
       describe '#ancestors' do
         it { expect(group.ancestors.to_sql).not_to include 'traversal_ids <@' }
       end
@@ -526,6 +530,10 @@ RSpec.describe Group do
         it { expect(group.descendants.to_sql).to include 'traversal_ids @>' }
       end
 
+      describe '#self_and_hierarchy' do
+        it { expect(group.self_and_hierarchy.to_sql).to include 'traversal_ids @>' }
+      end
+
       describe '#ancestors' do
         it { expect(group.ancestors.to_sql).to include "\"namespaces\".\"id\" = #{group.parent_id}" }
 

spec/models/namespace_spec.rb

@@ -1263,6 +1263,32 @@ RSpec.describe Namespace do
     end
   end
 
+  describe '#use_traversal_ids_for_self_and_hierarchy?' do
+    let_it_be(:namespace, reload: true) { create(:namespace) }
+
+    subject { namespace.use_traversal_ids_for_self_and_hierarchy? }
+
+    it { is_expected.to eq true }
+
+    it_behaves_like 'disabled feature flag when traversal_ids is blank'
+
+    context 'when use_traversal_ids_for_self_and_hierarchy feature flag is false' do
+      before do
+        stub_feature_flags(use_traversal_ids_for_self_and_hierarchy: false)
+      end
+
+      it { is_expected.to eq false }
+    end
+
+    context 'when use_traversal_ids? feature flag is false' do
+      before do
+        stub_feature_flags(use_traversal_ids: false)
+      end
+
+      it { is_expected.to eq false }
+    end
+  end
+
   describe '#users_with_descendants' do
     let(:user_a) { create(:user) }
     let(:user_b) { create(:user) }