misc: add setting to force synchronous rendering of cells (#49149)

The setting is used through a new fixture, `synchronous_cells`. It's
necessary to test views with cells which always use ajax rendering
without an headless browser or using the request factory.

combo/public/views.py

@@ -591,6 +591,8 @@ def publish_page(request, page, status=200, template_name=None):
     }
     ctx.update(getattr(request, 'extra_context_data', {}))
     modify_global_context(request, ctx)
+    if getattr(settings, 'COMBO_TEST_ALWAYS_RENDER_CELLS_SYNCHRONOUSLY', False):
+        ctx['synchronous'] = True
 
     for cell in cells:
         if cell.modify_global_context:

tests/conftest.py

@@ -57,3 +57,8 @@ def nocache(settings):
             'BACKEND': 'django.core.cache.backends.dummy.DummyCache',
         }
     }
+
+
+@pytest.fixture
+def synchronous_cells(settings):
+    settings.COMBO_TEST_ALWAYS_RENDER_CELLS_SYNCHRONOUSLY = True