manager: recreate full hierarchy when moving page to a new parent (#36127)

combo/manager/views.py

@@ -460,9 +460,18 @@ def cell_order(request, page_pk):
 def page_order(request):
     new_order = [int(x) for x in request.GET['new-order'].split(',')]
     moved_page = Page.objects.get(id=request.GET['moved-page-id'])
-    current_parent_id = moved_page.parent_id
     if request.GET['moved-page-new-parent']:
-        moved_page.parent_id = request.GET['moved-page-new-parent']
+        # recreate full hierarchy to avoid cycles
+        current_hierarchy = Page.objects.get(id=request.GET['moved-page-new-parent']).get_parents_and_self()
+        new_hierarchy = [x for x in current_hierarchy if not x.id == moved_page.id] + [moved_page]
+        for i, page in enumerate(new_hierarchy):
+            old_parent_id = page.parent_id
+            if i == 0:
+                page.parent_id = None
+            else:
+                page.parent_id = new_hierarchy[i-1].id
+            if old_parent_id != page.parent_id:
+                page.save()
     else:
         moved_page.parent_id = None
     moved_page.save()

tests/test_manager.py

@@ -277,6 +277,37 @@ def test_page_reorder(app, admin_user):
         'new-order': ','.join([str(x) for x in [page1.id, page2.id, page4.id, page3.id]])})
     assert Page.objects.get(id=page4.id).slug.startswith('three-')
 
+    # move a parent page as a child of its own child
+    for page in (page1, page2, page3, page4):
+        page.parent = None
+        page.save()
+    page2.parent = page1
+    page2.save()
+    page3.parent = page2
+    page3.save()
+    resp = app.get('/manage/pages/order', params={
+        'moved-page-id': page1.id,
+        'moved-page-new-parent': page3.id,
+        'new-order': ','.join([str(x) for x in [page2.id, page3.id, page1.id, page4.id]])})
+    assert Page.objects.get(id=page2.id).parent_id is None
+
+    for page in (page1, page2, page3, page4):
+        page.parent = None
+        page.save()
+    page2.parent = page1
+    page2.save()
+    page3.parent = page2
+    page3.save()
+    page4.parent = page3
+    page4.save()
+    resp = app.get('/manage/pages/order', params={
+        'moved-page-id': page2.id,
+        'moved-page-new-parent': page4.id,
+        'new-order': ','.join([str(x) for x in [page1.id, page3.id, page4.id, page2.id]])})
+    assert Page.objects.get(id=page1.id).parent_id is None
+    assert Page.objects.get(id=page3.id).parent_id == page1.id
+
+
 def test_export_page(app, admin_user):
     Page.objects.all().delete()
     page = Page(title='One', slug='one', template_name='standard')