Create work item with iteration

What does this MR do and why?

This MR adds the ability to assign an iteration to a work item on creation via GraphQL mutation workItemCreate.

The change allows us to reduce the complexity on the frontend because we can avoid chaining mutations workItemCreate and workItemUpdate (#367456 (comment 1098107478).)

How to set up and validate locally

• Prepare an iteration. Visit any group and navigate to Issues -> Iterations in the left sidebar.
  • Create a new iterations cadence by clicking New iteration cadence.
    • For simplicity, uncheck Enable automatic scheduling
  • To the created iterations cadence, add an iteration.
  • Grab the id of the created iteration by running gdk psql -c "SELECT id FROM sprints ORDER BY id DESC LIMIT 1;" in your terminal.

video walkthrough

demo

Sample query

mutation myMutation {
  workItemCreate(input: {
    projectPath: "gitlab-org/gitlab-test"
    workItemTypeId: "gid://gitlab/WorkItems::Type/1" # corresponds to Issue type
    title: "some work item"
    iterationWidget: {
      iterationId: "gid://gitlab/Iteration/4" # you might try out `null` and other values.
    }
  }) {
    errors
    workItem {
      id
      title
      widgets {
        type
        ... on WorkItemWidgetIteration {
          iteration {
            id
          }
        }
      }
    }
  }
}

MR acceptance checklist

This checklist encourages us to confirm any changes have been analyzed to reduce risks in quality, performance, reliability, security, and maintainability.

• I have evaluated the MR acceptance checklist for this MR.

Related to #367456 (closed)

ee/spec/services/work_items/widgets/iteration_service/create_service_spec.rb

@@ -2,7 +2,7 @@
 
 require 'spec_helper'
 
-RSpec.describe WorkItems::Widgets::IterationService::CreateService do
+RSpec.describe WorkItems::Widgets::IterationService::CreateService, feature_category: :project_management do
   let_it_be(:user) { create(:user) }
   let_it_be(:group) { create(:group) }
   let_it_be(:project) { create(:project, group: group) }
@@ -11,59 +11,10 @@
   let_it_be_with_reload(:work_item) { create(:work_item, :issue, project: project, author: user) }
 
   let(:widget) { work_item.widgets.find { |widget| widget.is_a?(WorkItems::Widgets::Iteration) } }
-  let(:params) { { iteration: iteration } }
 
-  describe '#create' do
+  describe '#before_create_callback' do
     subject { described_class.new(widget: widget, current_user: user).before_create_callback(params: params) }
 
-    before do
-      stub_licensed_features(iterations: true)
-    end
-
-    shared_examples 'iteration is unchanged' do
-      it 'does not change the iteration of the work item' do
-        expect { subject }
-          .to not_change { work_item.iteration }
-      end
-    end
-
-    context 'when iteration param is not present' do
-      let(:params) { {} }
-
-      it_behaves_like 'iteration is unchanged'
-    end
-
-    context 'when user can only update but not admin the work item' do
-      before do
-        project.add_guest(user)
-      end
-
-      it_behaves_like 'iteration is unchanged'
-    end
-
-    context 'when user can admin the work item' do
-      before do
-        project.add_reporter(user)
-      end
-
-      let(:params) { { iteration: iteration } }
-
-      it 'sets the iteration for the work item' do
-        expect { subject }
-          .to change { work_item.iteration }.to(iteration)
-      end
-
-      context "when iteration is from neither the work item's group nor its ancestors" do
-        let_it_be(:other_cadence) { create(:iterations_cadence, group: create(:group)) }
-        let_it_be(:other_iteration) { create(:iteration, iterations_cadence: other_cadence) }
-
-        let(:params) { { iteration: other_iteration } }
-
-        it 'does not set the iteration for the work item' do
-          expect { subject }
-            .to not_change(work_item, :iteration)
-        end
-      end
-    end
+    it_behaves_like 'iteration change is handled'
   end
 end