Tests for association manipulation on has many owned root

test/unit/view_model/active_record/has_many_test.rb

@@ -1085,6 +1085,65 @@ def new_model
       assert_equal(2, model.children.size)
       assert_equal('renamed', model.children.first.name)
     end
+
+    describe 'with association manipulation' do
+      it 'appends a child' do
+        view = create_viewmodel!
+
+        view.append_associated(:children, { '_type' => 'Child', 'name' => 'newchildname' })
+
+        view.model.reload
+        assert_equal(3, view.children.size)
+        assert_equal('newchildname', view.children.last.name)
+      end
+
+      it 'inserts a child' do
+        view = create_viewmodel!
+        c1 = view.children.first
+
+        view.append_associated(:children,
+                               { '_type' => 'Child', 'name' => 'newchildname' },
+                               after: c1.to_reference)
+        view.model.reload
+
+        assert_equal(3, view.children.size)
+        assert_equal('newchildname', view.children[1].name)
+      end
+
+      it 'moves a child' do
+        view = create_viewmodel!
+        c1, c2 = view.children
+
+        view.append_associated(:children,
+                               { '_type' => 'Child', 'id' => c2.id },
+                               before: c1.to_reference)
+        view.model.reload
+
+        assert_equal(2, view.children.size)
+        assert_equal(['c2', 'c1'], view.children.map(&:name))
+      end
+
+      it 'replaces children' do
+        view = create_viewmodel!
+        view.replace_associated(:children,
+                                [{ '_type' => 'Child', 'name' => 'newchildname' }])
+
+        view.model.reload
+
+        assert_equal(1, view.children.size)
+        assert_equal('newchildname', view.children[0].name)
+      end
+
+      it 'deletes a child' do
+        view = create_viewmodel!
+        view.delete_associated(:children, view.children.first.id)
+
+        view.model.reload
+
+        assert_equal(1, view.children.size)
+        assert_equal('c2', view.children[0].name)
+      end
+    end
   end
 
   describe 'renaming associations' do