Use Keyset pagination

- Apply reviewer feedback

app/graphql/resolvers/board_list_issues_resolver.rb

@@ -9,7 +9,7 @@ module Resolvers
     def resolve(**args)
       # rubocop: disable CodeReuse/ActiveRecord
       service = Boards::Issues::ListService.new(list.board.resource_parent, context[:current_user], { board_id: list.board.id, id: list.id })
-      Gitlab::Graphql::Pagination::OffsetActiveRecordRelationConnection.new(service.execute)
+      service.execute.reorder("issues.relative_position ASC, issues.id DESC")
       # rubocop: enable CodeReuse/ActiveRecord
     end
   end

app/graphql/types/issuable_connection_type.rb

@@ -7,7 +7,7 @@ module Types
           description: 'Total count of collection'
 
     def count
-      relation = object.items.reorder(nil)
+      relation = object.items
 
       if relation.try(:group_values)&.present?
         relation.size.keys.size

spec/graphql/resolvers/board_list_issues_resolver_spec.rb

@@ -20,17 +20,12 @@ RSpec.describe Resolvers::BoardListIssuesResolver do
     # auth is handled by the parent object
     context 'when authorized' do
       let!(:list) { create(:list, board: board, label: label) }
-      let!(:issue1) { create(:issue, project: project, labels: [label], relative_position: 10, id: 44) }
-      let!(:issue2) { create(:issue, project: project, labels: [label], relative_position: 12, id: 45) }
-      let!(:issue3) { create(:issue, project: project, labels: [label], relative_position: 10, id: 46) }
-
-      it 'calls Boards::Issues::ListService with the correct arguments' do
-        expect(Boards::Issues::ListService).to receive(:new).with(board_parent, user, { board_id: board.id, id: list.id }).and_call_original
-
-        resolve_board_list_issues
-      end
 
       it 'returns the issues in the correct order' do
+        issue1 = create(:issue, project: project, labels: [label], relative_position: 10)
+        issue2 = create(:issue, project: project, labels: [label], relative_position: 12)
+        issue3 = create(:issue, project: project, labels: [label], relative_position: 10)
+
         # by relative_position and then ID
         issues = resolve_board_list_issues
 

spec/requests/api/graphql/boards/board_list_issues_query_spec.rb

@@ -51,10 +51,10 @@ RSpec.describe 'get board lists' do
   shared_examples 'group and project board list issues query' do
     let!(:board) { create(:board, resource_parent: board_parent) }
     let!(:label_list) { create(:list, board: board, label: label, position: 10) }
-    let!(:issue1) { create(:issue, project: issue_project, labels: [label], relative_position: 9, id: 10) }
-    let!(:issue2) { create(:issue, project: issue_project, labels: [label], relative_position: 2, id: 11) }
-    let!(:issue3) { create(:issue, project: issue_project, labels: [label], relative_position: 9, id: 12) }
-    let!(:issue4) { create(:issue, project: issue_project, labels: [label2], relative_position: 432, id: 13) }
+    let!(:issue1) { create(:issue, project: issue_project, labels: [label], relative_position: 9) }
+    let!(:issue2) { create(:issue, project: issue_project, labels: [label], relative_position: 2) }
+    let!(:issue3) { create(:issue, project: issue_project, labels: [label], relative_position: 9) }
+    let!(:issue4) { create(:issue, project: issue_project, labels: [label2], relative_position: 432) }
 
     context 'when the user does not have access to the board' do
       it 'returns nil' do