1 files changed, 13 insertions, 5 deletions

diff --git a/spec/models/work_items/parent_link_spec.rb b/spec/models/work_items/parent_link_spec.rb
index 9516baa7340..a16b15bbfc9 100644
--- a/spec/models/work_items/parent_link_spec.rb
+++ b/spec/models/work_items/parent_link_spec.rb
@@ -9,38 +9,46 @@ RSpec.describe WorkItems::ParentLink do
   end
 
   describe 'validations' do
+    subject { build(:parent_link) }
+
     it { is_expected.to validate_presence_of(:work_item) }
     it { is_expected.to validate_presence_of(:work_item_parent) }
+    it { is_expected.to validate_uniqueness_of(:work_item) }
 
     describe 'hierarchy' do
       let_it_be(:project) { create(:project) }
       let_it_be(:issue) { build(:work_item, project: project) }
+      let_it_be(:incident) { build(:work_item, :incident, project: project) }
       let_it_be(:task1) { build(:work_item, :task, project: project) }
       let_it_be(:task2) { build(:work_item, :task, project: project) }
 
-      it 'is valid if not-task parent has task child' do
+      it 'is valid if issue parent has task child' do
         expect(build(:parent_link, work_item: task1, work_item_parent: issue)).to be_valid
       end
 
+      it 'is valid if incident parent has task child' do
+        expect(build(:parent_link, work_item: task1, work_item_parent: incident)).to be_valid
+      end
+
       it 'is not valid if child is not task' do
         link = build(:parent_link, work_item: issue)
 
         expect(link).not_to be_valid
-        expect(link.errors[:work_item]).to include('Only Task can be assigned as a child in hierarchy.')
+        expect(link.errors[:work_item]).to include('only Task can be assigned as a child in hierarchy.')
       end
 
       it 'is not valid if parent is task' do
         link = build(:parent_link, work_item_parent: task1)
 
         expect(link).not_to be_valid
-        expect(link.errors[:work_item_parent]).to include('Only Issue can be parent of Task.')
+        expect(link.errors[:work_item_parent]).to include('only Issue and Incident can be parent of Task.')
       end
 
       it 'is not valid if parent is in other project' do
         link = build(:parent_link, work_item_parent: task1, work_item: build(:work_item))
 
         expect(link).not_to be_valid
-        expect(link.errors[:work_item_parent]).to include('Parent must be in the same project as child.')
+        expect(link.errors[:work_item_parent]).to include('parent must be in the same project as child.')
       end
 
       context 'when parent already has maximum number of links' do
@@ -54,7 +62,7 @@ RSpec.describe WorkItems::ParentLink do
           link2 = build(:parent_link, work_item_parent: issue, work_item: task2)
 
           expect(link2).not_to be_valid
-          expect(link2.errors[:work_item_parent]).to include('Parent already has maximum number of children.')
+          expect(link2.errors[:work_item_parent]).to include('parent already has maximum number of children.')
         end
 
         it 'existing link is still valid' do