#35417: RequestContext.new creates a context that cannot be flattened -----------------------------------------+------------------------ Reporter: Lily Foote | Owner: nobody Type: Uncategorized | Status: new Component: Uncategorized | Version: 5.0 Severity: Normal | Keywords: Triage Stage: Unreviewed | Has patch: 0 Needs documentation: 0 | Needs tests: 0 Patch needs improvement: 0 | Easy pickings: 0 UI/UX: 0 | -----------------------------------------+------------------------ In [https://github.com/django/django/blob/c187f5f9242b681abaa199173e02066997439425/django/template/library.py#L273 InclusionNode.render] Django creates a {{{new_context}}} from two existing contexts ({{{context}}} and {{{_dict}}}) by calling {{{new_context = context.new(_dict)}}}. These can both be instances of {{{RequestContext}}} leading to {{{new_context}}} also being a {{{RequestContext}}} (I have not tried with any other context types). However, calling {{{new_context.flatten()}}} raises a {{{ValueError}}}:
{{{ ValueError: dictionary update sequence element #0 has length 1; 2 is required }}} I can reproduce this in a small test: {{{ from django.template.context import RequestContext from django.test import RequestFactory, TestCase class RequestContextTestCase(TestCase): def test_flatten_request_context_new(self): factory = RequestFactory() request = factory.get("/foo/") context = RequestContext(request) context_2 = RequestContext(request) context_3 = context.new(context_2) self.assertEqual( context_3.flatten(), {"False": False, "None": None, "True": True} ) }}} I discovered this when running Kolo on a Django admin view (http://127.0.0.1:8000/admin/auth/user/). Kolo calls {{{context.flatten()}}} internally when introspecting a template during rendering, which leads to this exception: {{{ Traceback (most recent call last): File "/home/lily/work/kloppindustries/kolo/python/src/kolo/profiler.py", line 170, in __call__ frame_data = processor.process( ^^^^^^^^^^^^^^^^^^ File "/home/lily/work/kloppindustries/kolo/python/src/kolo/plugins.py", line 107, in process data.update(self.process_extra(frame, event, arg, self.context)) ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ File "/home/lily/work/kloppindustries/kolo/python/src/kolo/filters/django.py", line 89, in process_django_template template_context = template_context.flatten() ^^^^^^^^^^^^^^^^^^^^^^^^^^ File "/home/lily/.local/share/lilyenv/virtualenvs/kolo- sandbox/3.12/lib/python3.12/site-packages/django/template/context.py", line 120, in flatten flat.update(d) ValueError: dictionary update sequence element #0 has length 3; 2 is required }}} -- Ticket URL: <https://code.djangoproject.com/ticket/35417> Django <https://code.djangoproject.com/> The Web framework for perfectionists with deadlines. -- You received this message because you are subscribed to the Google Groups "Django updates" group. To unsubscribe from this group and stop receiving emails from it, send an email to django-updates+unsubscr...@googlegroups.com. To view this discussion on the web visit https://groups.google.com/d/msgid/django-updates/0107018f2f8b2174-0d33b315-bbe2-4ea2-a2eb-40f7e4c1be6f-000000%40eu-central-1.amazonses.com.