tests: Add test for related field descriptor

Author: fsbraun

djangocms_frontend/cms_plugins.py

@@ -2,7 +2,7 @@
 from cms.plugin_base import CMSPluginBase
 from django.utils.encoding import force_str
 
-from djangocms_frontend.helpers import get_related_object
+from djangocms_frontend.helpers import get_related
 
 if hasattr(CMSPluginBase, "edit_field"):
     # FrontendEditable functionality already implemented in core?
@@ -12,15 +12,6 @@
     from .helpers import FrontendEditableAdminMixin
 
 
-def _get_related(instance, key):
-    def get_related():
-        obj = get_related_object(instance.config, key)
-        setattr(instance, key, obj)
-        return obj
-    get_related.__name__ = key
-    return get_related
-
-
 class CMSUIPlugin(FrontendEditableAdminMixin, CMSPluginBase):
     render_template = "djangocms_frontend/html_container.html"
     change_form_template = "djangocms_frontend/admin/base.html"
@@ -32,7 +23,7 @@ def render(self, context, instance, placeholder):
         for key, value in instance.config.items():
             if isinstance(value, dict) and set(value.keys()) == {"pk", "model"}:
                 if key not in instance.__dir__():  # hasattr would return the value in the config dict
-                    setattr(instance, key, _get_related(instance, key))
+                    setattr(instance.__class__, key, get_related(key))
         return super().render(context, instance, placeholder)
 
     def get_plugin_urls(self):

djangocms_frontend/helpers.py

@@ -31,6 +31,18 @@ def get_related_object(scope, field_name):
     return relobj
 
 
+class get_related:
+    """Descriptor lazily getting related objects from the config dict."""
+    def __init__(self, key):
+        self.key = key
+
+    def __get__(self, instance, owner):
+        obj = get_related_object(instance.config, self.key)
+        if obj is not None:
+            setattr(instance, self.key, obj)
+        return obj
+
+
 def insert_fields(fieldsets, new_fields, block=None, position=-1, blockname=None, blockattrs=None):
     """
     creates a copy of fieldsets inserting the new fields either in the indexed block at the position,

tests/image/test_plugins.py

@@ -45,7 +45,7 @@ def test_plugin(self):
             plugin_type=ImagePlugin.__name__,
             language=self.language,
             config={
-                "image": {"pk": self.image.id, "model": "filer.Image"},
+                "picture": {"pk": self.image.id, "model": "filer.Image"},
                 "picture_fluid": False,
                 "picture_rounded": True,
                 "picture_thumbnail": True,

tests/link/test_plugins.py

@@ -71,6 +71,8 @@ def test_plugin(self):
         self.assertEqual(response.status_code, 200)
         self.assertContains(response, "btn-primary")
         self.assertContains(response, 'href="/content/"')
+        # Finally, test the descriptor
+        self.assertEqual(plugin.internal_link, self.page)
 
         # alternate version broken link
         plugin = add_plugin(