[registry] add assertion useful if e.g. arguments are inversed by inadvertance

1 files changed, 2 insertions, 0 deletions

diff --git a/registry.py b/registry.py
index 29f3c56..cebed8e 100644
--- a/registry.py
+++ b/registry.py
@@ -519,6 +519,8 @@ class RegistryStore(dict):
         :meth:`~logilab.common.registry.RegistryStore.register_and_replace`
         for instance)
         """
+        assert isinstance(modname, basestring), \
+            'modname expected to be a module name (ie string), got %r' % modname
         for obj in objects:
             try:
                 if obj.__module__ != modname or obj in butclasses: