Ticket #12065: admin.patch

django/contrib/flatpages/admin.py

@@ -11 +11 @@
         error_message = _("This value must contain only letters, numbers,"
                           " underscores, dashes or slashes."))
 
+    def clean_sites(self):
+        sites = self.cleaned_data['sites']
+        url = self.cleaned_data['url']
+        errors = []
+        url_clash_query = FlatPage.objects.filter(url=url)
+        if self.instance.pk:
+            url_clash_query = url_clash_query.exclude(pk=self.instance.pk)
+        for site in sites:
+            clashes = url_clash_query.filter(sites=site)
+            for clash in clashes:
+                errors.append(_("There is already a page with the same url for site %s.") % site)
+        if errors:
+            raise forms.ValidationError, errors
+        return sites
+
     class Meta:
         model = FlatPage