Produce error when assigning Enum or TypedDict as attribute (#8107)

Author: TH3CHARLie

mypy/semanal.py

@@ -2161,14 +2161,17 @@ def analyze_typeddict_assign(self, s: AssignmentStmt) -> bool:
         """Check if s defines a typed dict."""
         if isinstance(s.rvalue, CallExpr) and isinstance(s.rvalue.analyzed, TypedDictExpr):
             return True  # This is a valid and analyzed typed dict definition, nothing to do here.
-        if len(s.lvalues) != 1 or not isinstance(s.lvalues[0], NameExpr):
+        if len(s.lvalues) != 1 or not isinstance(s.lvalues[0], (NameExpr, MemberExpr)):
             return False
         lvalue = s.lvalues[0]
         name = lvalue.name
         is_typed_dict, info = self.typed_dict_analyzer.check_typeddict(s.rvalue, name,
                                                                        self.is_func_scope())
         if not is_typed_dict:
             return False
+        if isinstance(lvalue, MemberExpr):
+            self.fail("TypedDict type as attribute is not supported", lvalue)
+            return False
         # Yes, it's a valid typed dict, but defer if it is not ready.
         if not info:
             self.mark_incomplete(name, lvalue, becomes_typeinfo=True)

mypy/semanal_enum.py

@@ -8,7 +8,7 @@
 from mypy.nodes import (
     Expression, Context, TypeInfo, AssignmentStmt, NameExpr, CallExpr, RefExpr, StrExpr,
     UnicodeExpr, TupleExpr, ListExpr, DictExpr, Var, SymbolTableNode, MDEF, ARG_POS,
-    EnumCallExpr
+    EnumCallExpr, MemberExpr
 )
 from mypy.semanal_shared import SemanticAnalyzerInterface
 from mypy.options import Options
@@ -25,13 +25,16 @@ def process_enum_call(self, s: AssignmentStmt, is_func_scope: bool) -> bool:
         Return True if this looks like an Enum definition (but maybe with errors),
         otherwise return False.
         """
-        if len(s.lvalues) != 1 or not isinstance(s.lvalues[0], NameExpr):
+        if len(s.lvalues) != 1 or not isinstance(s.lvalues[0], (NameExpr, MemberExpr)):
             return False
         lvalue = s.lvalues[0]
         name = lvalue.name
         enum_call = self.check_enum_call(s.rvalue, name, is_func_scope)
         if enum_call is None:
             return False
+        if isinstance(lvalue, MemberExpr):
+            self.fail("Enum type as attribute is not supported", lvalue)
+            return False
         # Yes, it's a valid Enum definition. Add it to the symbol table.
         self.api.add_symbol(name, enum_call, s)
         return True

test-data/unit/check-enum.test

@@ -908,3 +908,12 @@ def func(x: Union[int, None, Empty] = _empty) -> int:
         reveal_type(x)  # N: Revealed type is 'builtins.int'
         return x + 2
 [builtins fixtures/primitives.pyi]
+
+[case testAssignEnumAsAttribute]
+from enum import Enum
+
+class A:
+    def __init__(self) -> None:
+        self.b = Enum("x", [("foo", "bar")])  # E: Enum type as attribute is not supported
+
+reveal_type(A().b)  # N: Revealed type is 'Any'

test-data/unit/check-typeddict.test

@@ -1987,3 +1987,14 @@ reveal_type(foo['bar'])  # N: Revealed type is 'builtins.list[Any]'
 reveal_type(foo['baz'])  # N: Revealed type is 'builtins.list[Any]'
 [builtins fixtures/dict.pyi]
 [typing fixtures/typing-full.pyi]
+
+[case testAssignTypedDictAsAttribute]
+from typing import TypedDict
+
+class A:
+    def __init__(self) -> None:
+        self.b = TypedDict('b', {'x': int, 'y': str})  # E: TypedDict type as attribute is not supported
+
+reveal_type(A().b)  # N: Revealed type is 'Any'
+[builtins fixtures/dict.pyi]
+[typing fixtures/typing-full.pyi]