1 files changed, 93 insertions, 0 deletions
diff --git a/spec/requests/api/graphql/mutations/work_items/delete_task_spec.rb b/spec/requests/api/graphql/mutations/work_items/delete_task_spec.rb
new file mode 100644
index 00000000000..05d3587d342
--- /dev/null
+++ b/spec/requests/api/graphql/mutations/work_items/delete_task_spec.rb
@@ -0,0 +1,93 @@
+# frozen_string_literal: true
+
+require 'spec_helper'
+
+RSpec.describe "Delete a task in a work item's description" do
+  include GraphqlHelpers
+
+  let_it_be(:project) { create(:project) }
+  let_it_be(:developer) { create(:user).tap { |user| project.add_developer(user) } }
+  let_it_be(:task) { create(:work_item, :task, project: project, author: developer) }
+  let_it_be(:work_item, refind: true) do
+    create(:work_item, project: project, description: "- [ ] #{task.to_reference}+", lock_version: 3)
+  end
+
+  before_all do
+    create(:issue_link, source_id: work_item.id, target_id: task.id)
+  end
+
+  let(:lock_version) { work_item.lock_version }
+  let(:input) do
+    {
+      'id' => work_item.to_global_id.to_s,
+      'lockVersion' => lock_version,
+      'taskData' => {
+        'id' => task.to_global_id.to_s,
+        'lineNumberStart' => 1,
+        'lineNumberEnd' => 1
+      }
+    }
+  end
+
+  let(:mutation) { graphql_mutation(:workItemDeleteTask, input) }
+  let(:mutation_response) { graphql_mutation_response(:work_item_delete_task) }
+
+  context 'the user is not allowed to update a work item' do
+    let(:current_user) { create(:user) }
+
+    it_behaves_like 'a mutation that returns a top-level access error'
+  end
+
+  context 'when user can update the description but not delete the task' do
+    let(:current_user) { create(:user).tap { |u| project.add_developer(u) } }
+
+    it_behaves_like 'a mutation that returns a top-level access error'
+  end
+
+  context 'when user has permissions to remove a task' do
+    let(:current_user) { developer }
+
+    it 'removes the task from the work item' do
+      expect do
+        post_graphql_mutation(mutation, current_user: current_user)
+        work_item.reload
+      end.to change(WorkItem, :count).by(-1).and(
+        change(IssueLink, :count).by(-1)
+      ).and(
+        change(work_item, :description).from("- [ ] #{task.to_reference}+").to('')
+      )
+
+      expect(response).to have_gitlab_http_status(:success)
+      expect(mutation_response['workItem']).to include('id' => work_item.to_global_id.to_s)
+    end
+
+    context 'when removing the task fails' do
+      let(:lock_version) { 2 }
+
+      it 'makes no changes to the DB and returns an error message' do
+        expect do
+          post_graphql_mutation(mutation, current_user: current_user)
+          work_item.reload
+        end.to not_change(WorkItem, :count).and(
+          not_change(work_item, :description)
+        )
+
+        expect(mutation_response['errors']).to contain_exactly('Stale work item. Check lock version')
+      end
+    end
+
+    context 'when the work_items feature flag is disabled' do
+      before do
+        stub_feature_flags(work_items: false)
+      end
+
+      it 'does nothing and returns and error' do
+        expect do
+          post_graphql_mutation(mutation, current_user: current_user)
+        end.to not_change(WorkItem, :count)
+
+        expect(mutation_response['errors']).to contain_exactly('`work_items` feature flag disabled for this project')
+      end
+    end
+  end
+end