Add test for sum of issues weight on issue boards

qa/qa/specs/features/ee/browser_ui/2_plan/issue_boards/sum_of_issues_weights_spec.rb

+# frozen_string_literal: true
+
+module QA
+  context 'Plan' do
+    describe 'Sum of issues weights on issue board' do
+      let(:label_board_list) do
+        EE::Resource::Board::BoardList::Project::LabelBoardList.fabricate_via_api!
+      end
+
+      let(:label) { 'Doing' }
+      let(:weight_for_issue_1) { 5 }
+      let(:weight_for_issue_2) { 3 }
+
+      before do
+        Runtime::Browser.visit(:gitlab, Page::Main::Login)
+        Page::Main::Login.perform(&:sign_in_using_credentials)
+
+        Resource::Issue.fabricate_via_api! do |issue|
+          issue.project = label_board_list.project
+          issue.title = 'Issue 1'
+          issue.labels = [label]
+          issue.weight = weight_for_issue_1
+        end
+
+        Resource::Issue.fabricate_via_api! do |issue|
+          issue.project = label_board_list.project
+          issue.title = 'Issue 2'
+          issue.labels = [label]
+          issue.weight = weight_for_issue_2
+        end
+
+        label_board_list.project.visit!
+        Page::Project::Menu.perform(&:go_to_boards)
+      end
+
+      it 'shows the sum of issues weights in the board list\'s header' do
+        EE::Page::Project::Issue::Board::Show.perform do |show|
+          expect(show.boards_list_header_with_index(1)).to have_content(weight_for_issue_1 + weight_for_issue_2)
+        end
+      end
+    end
+  end
+end