Support include_ancestors to group milestone query

for the GraphQL query

app/graphql/resolvers/group_milestones_resolver.rb

@@ -5,18 +5,37 @@ module Resolvers
   class GroupMilestonesResolver < MilestonesResolver
     argument :include_descendants, GraphQL::BOOLEAN_TYPE,
              required: false,
-             description: 'Also return milestones in all subgroups and subprojects.'
+             description: 'Include milestones from all subgroups and subprojects.'
+    argument :include_ancestors, GraphQL::BOOLEAN_TYPE,
+             required: false,
+             description: 'Include milestones from all parent groups.'
 
     type Types::MilestoneType.connection_type, null: true
 
     private
 
     def parent_id_parameters(args)
-      return { group_ids: parent.id } unless args[:include_descendants].present?
+      include_ancestors = args[:include_ancestors].present?
+      include_descendants = args[:include_descendants].present?
+      return { group_ids: parent.id } unless include_ancestors || include_descendants
+
+      group_ids = if include_ancestors && include_descendants
+                    parent.self_and_hierarchy
+                  elsif include_ancestors
+                    parent.self_and_ancestors
+                  else
+                    parent.self_and_descendants
+                  end
+
+      project_ids = if include_descendants
+                      group_projects.with_issues_or_mrs_available_for_user(current_user)
+                    else
+                      nil
+                    end
 
       {
-        group_ids: parent.self_and_descendants.public_or_visible_to_user(current_user).select(:id),
-        project_ids: group_projects.with_issues_or_mrs_available_for_user(current_user)
+        group_ids: group_ids.public_or_visible_to_user(current_user).select(:id),
+        project_ids: project_ids
       }
     end
 

changelogs/unreleased/323433-add-includeancestors-to-group-milestones-graphql.yml

+---
+title: Support include_ancestors when querying group milestones via GraphQL
+merge_request: 56667
+author:
+type: added

spec/graphql/resolvers/group_milestones_resolver_spec.rb

@@ -136,5 +136,56 @@ RSpec.describe Resolvers::GroupMilestonesResolver do
         expect(resolve_group_milestones(args)).to match_array([milestone1, milestone2, milestone3])
       end
     end
+
+    describe 'include_descendants and include_ancestors' do
+      let_it_be(:parent_group) { create(:group, :public) }
+      let_it_be(:group) { create(:group, :public, parent: parent_group) }
+      let_it_be(:accessible_group) { create(:group, :private, parent: group) }
+      let_it_be(:accessible_project) { create(:project, group: accessible_group) }
+      let_it_be(:inaccessible_group) { create(:group, :private, parent: group) }
+      let_it_be(:inaccessible_project) { create(:project, :private, group: group) }
+      let_it_be(:milestone1) { create(:milestone, group: group) }
+      let_it_be(:milestone2) { create(:milestone, group: accessible_group) }
+      let_it_be(:milestone3) { create(:milestone, project: accessible_project) }
+      let_it_be(:milestone4) { create(:milestone, group: inaccessible_group) }
+      let_it_be(:milestone5) { create(:milestone, project: inaccessible_project) }
+      let_it_be(:milestone6) { create(:milestone, group: parent_group) }
+
+      before do
+        accessible_group.add_developer(current_user)
+      end
+
+      context 'when including neither ancestor or descendant milestones in a public group' do
+        let(:args) { {} }
+
+        it 'finds milestones only in accessible projects and groups' do
+          expect(resolve_group_milestones(args)).to match_array([milestone1])
+        end
+      end
+
+      context 'when including descendant milestones in a public group' do
+        let(:args) { { include_descendants: true } }
+
+        it 'finds milestones only in accessible projects and groups' do
+          expect(resolve_group_milestones(args)).to match_array([milestone1, milestone2, milestone3])
+        end
+      end
+
+      context 'when including ancestor milestones in a public group' do
+        let(:args) { { include_ancestors: true } }
+
+        it 'finds milestones only in accessible projects and groups' do
+          expect(resolve_group_milestones(args)).to match_array([milestone1, milestone6])
+        end
+      end
+
+      context 'when including both ancestor or descendant milestones in a public group' do
+        let(:args) { { include_descendants: true, include_ancestors: true } }
+
+        it 'finds milestones only in accessible projects and groups' do
+          expect(resolve_group_milestones(args)).to match_array([milestone1, milestone2, milestone3, milestone6])
+        end
+      end
+    end
   end
 end

spec/requests/api/graphql/group/milestones_spec.rb

@@ -9,12 +9,14 @@ RSpec.describe 'Milestones through GroupQuery' do
   let_it_be(:now) { Time.now }
 
   describe 'Get list of milestones from a group' do
-    let_it_be(:group) { create(:group) }
+    let_it_be(:parent_group) { create(:group) }
+    let_it_be(:group) { create(:group, parent: parent_group) }
     let_it_be(:milestone_1) { create(:milestone, group: group) }
     let_it_be(:milestone_2) { create(:milestone, group: group, state: :closed, start_date: now, due_date: now + 1.day) }
     let_it_be(:milestone_3) { create(:milestone, group: group, start_date: now, due_date: now + 2.days) }
     let_it_be(:milestone_4) { create(:milestone, group: group, state: :closed, start_date: now - 2.days, due_date: now - 1.day) }
     let_it_be(:milestone_from_other_group) { create(:milestone, group: create(:group)) }
+    let_it_be(:parent_milestone) { create(:milestone, group: parent_group) }
 
     let(:milestone_data) { graphql_data['group']['milestones']['edges'] }
 
@@ -64,14 +66,32 @@ RSpec.describe 'Milestones through GroupQuery' do
         accessible_group.add_developer(user)
       end
 
-      it 'returns milestones also from subgroups and subprojects visible to user' do
-        fetch_milestones(user, args)
+      context 'when including decendants' do
+        let(:args) { { include_descendants: true } }
+
+        it 'returns milestones also from subgroups and subprojects visible to user' do
+          fetch_milestones(user, args)
+
+          expect_array_response(
+            milestone_1.to_global_id.to_s, milestone_2.to_global_id.to_s,
+            milestone_3.to_global_id.to_s, milestone_4.to_global_id.to_s,
+            submilestone_1.to_global_id.to_s, submilestone_2.to_global_id.to_s
+          )
+        end
+      end
+
+      context 'when including ancestors' do
+        let(:args) { { include_ancestors: true } }
 
-        expect_array_response(
-          milestone_1.to_global_id.to_s, milestone_2.to_global_id.to_s,
-          milestone_3.to_global_id.to_s, milestone_4.to_global_id.to_s,
-          submilestone_1.to_global_id.to_s, submilestone_2.to_global_id.to_s
-        )
+        it 'returns milestones from ancestor groups' do
+          fetch_milestones(user, args)
+
+          expect_array_response(
+            milestone_1.to_global_id.to_s, milestone_2.to_global_id.to_s,
+            milestone_3.to_global_id.to_s, milestone_4.to_global_id.to_s,
+            parent_milestone.to_global_id.to_s
+          )
+        end
       end
     end