Added workaround for deleting pages with HtmlPageTranslation on it.

This is a workaround to handle #47

CHANGES.rst

@@ -8,6 +8,7 @@ Changes in version 0.9 (dev)
 * Change ``slug`` size to 100 characters.
 * Added ``FluentContentsPage.create_placeholder(slot)`` API.
 * Added ``--mptt-only`` option to ``manage.py rebuild_page_tree`` command.
+* Fix deleting pages with ``HtmlPageTranslation``.
 
 
 Released in 0.9b4:

fluent_pages/models/db.py

@@ -650,6 +650,17 @@ def meta_robots(self):
         else:
             return None
 
+    def delete(self, *args, **kwargs):
+        # Fix deleting pages, Django's collector doesn't detect the HtmlPageTranslation model
+        # because the FK points to a proxy. This is a workaround for:
+        # https://code.djangoproject.com/ticket/16128
+        # https://code.djangoproject.com/ticket/18491
+        # By using .all() we avoid the get_query_set/get_queryset() difference.
+        self.seo_translations.all().delete()  # Accesses RelatedManager
+
+        # Continue regular delete.
+        super(HtmlPage, self).delete(*args, **kwargs)
+