Disallow attribute access in Record and subclasses

Author: bryanforbes

asyncpg/mypy/__init__.py

@@ -28,8 +28,9 @@ def get_attribute_hook(self, fullname: str) \
         class_name, _, _ = fullname.rpartition('.')
         symbol = self.lookup_fully_qualified(class_name)
 
-        if symbol and isinstance(symbol.node, mypy.nodes.TypeInfo) and \
-                symbol.node.has_base(common.RECORD_NAME):
+        if symbol is not None and \
+                isinstance(symbol.node, mypy.nodes.TypeInfo) and \
+                utils.is_record(symbol.node):
             return hooks.record_attribute
 
         return None
@@ -38,12 +39,6 @@ def get_customize_class_mro_hook(self, fullname: str) \
             -> typing.Optional[common.ClassDefHook]:
         return hooks.mark_record
 
-    def get_base_class_hook(self, fullname: str) \
-            -> typing.Optional[common.ClassDefHook]:
-        if fullname == common.RECORD_NAME:
-            return hooks.record_final_attributes
-        return None
-
 
 def plugin(version: str) -> typing.Type[mypy.plugin.Plugin]:
     return AsyncpgPlugin

asyncpg/mypy/hooks.py

@@ -15,27 +15,17 @@ def mark_record(ctx: mypy.plugin.ClassDefContext) -> None:
         utils.mark_record(ctx.cls.info)
 
 
-def record_final_attributes(ctx: mypy.plugin.ClassDefContext) -> None:
-    if utils.is_record(ctx.cls.info):
-        for name, value in ctx.cls.info.names.items():
-            # set all properties as Final so they can't be set
-            if isinstance(value.node, mypy.nodes.Var):
-                value.node.is_final = True
-                value.node.final_set_in_init = True
-                value.node.final_unset_in_class = True
-
-
 def record_attribute(ctx: mypy.plugin.AttributeContext) \
         -> mypy.types.Type:
     if isinstance(ctx.type, mypy.types.Instance) and \
             utils.is_record(ctx.type.type):
         assert isinstance(ctx.context, mypy.nodes.MemberExpr)
-        symbol = ctx.type.type.get(ctx.context.name)
 
-        if symbol is None:
-            ctx.api.fail('"{}" has no attribute "{}"'
-                         .format(ctx.type.type.name, ctx.context.name),
-                         ctx.context)
+        # raise an error when users try to access the keys defined
+        # using attribute notation
+        ctx.api.fail('"{}" has no attribute "{}"'
+                     .format(ctx.type.type.name, ctx.context.name),
+                     ctx.context)
 
     return ctx.default_attr_type
 

asyncpg/protocol/protocol.pyi

@@ -216,7 +216,6 @@ class Record:
     def items(self) -> Iterator[Tuple[str, Any]]: ...
     def keys(self) -> Iterator[str]: ...
     def values(self) -> Iterator[Any]: ...
-    def __getattribute__(self, attr: str) -> Any: ...
     @overload
     def __getitem__(self, index: str) -> Any: ...
     @overload