Clearer docs for actor_matches_allow

datasette/utils/__init__.py

@@ -867,7 +867,8 @@ async def async_call_with_supported_arguments(fn, **kwargs):
 
 
 def actor_matches_allow(actor, allow):
-    actor = actor or {}
+    if actor is None:
+        actor = {"anonymous": True}
     if allow is None:
         return True
     for key, values in allow.items():

docs/authentication.rst

@@ -239,7 +239,7 @@ To limit this ability for just one specific database, use this:
 actor_matches_allow()
 =====================
 
-Plugins that wish to implement the same permissions scheme as canned queries can take advantage of the ``datasette.utils.actor_matches_allow(actor, allow)`` function:
+Plugins that wish to implement this same ``"allow"`` block permissions scheme can take advantage of the ``datasette.utils.actor_matches_allow(actor, allow)`` function:
 
 .. code-block:: python