Sync enum members logic in typeanal and checkmember (#19687)

Fixes #19686.
Fixes #15540.
Fixes #14600.

Author: sterliakov

mypy/checkmember.py

@@ -1349,9 +1349,6 @@ def analyze_enum_class_attribute_access(
     # Skip these since Enum will remove it
     if name in EXCLUDED_ENUM_ATTRIBUTES:
         return report_missing_attribute(mx.original_type, itype, name, mx)
-    # Dunders and private names are not Enum members
-    if name.startswith("__") and name.replace("_", "") != "":
-        return None
 
     node = itype.type.get(name)
     if node and node.type:
@@ -1364,6 +1361,9 @@ def analyze_enum_class_attribute_access(
         ):
             return proper.args[0]
 
+    if name not in itype.type.enum_members:
+        return None
+
     enum_literal = LiteralType(name, fallback=itype)
     return itype.copy_modified(last_known_value=enum_literal)
 

mypy/typeanal.py

@@ -988,7 +988,7 @@ def analyze_unbound_type_without_type_info(
             isinstance(sym.node, Var)
             and sym.node.info
             and sym.node.info.is_enum
-            and not sym.node.name.startswith("__")
+            and sym.node.name in sym.node.info.enum_members
         ):
             value = sym.node.name
             base_enum_short_name = sym.node.info.name

test-data/unit/check-enum.test

@@ -457,7 +457,8 @@ class F(Generic[T], Enum):  # E: Enum class cannot be generic
     x: T
     y: T
 
-reveal_type(F[int].x)  # N: Revealed type is "__main__.F[builtins.int]"
+reveal_type(F[int].x)  # E: Access to generic instance variables via class is ambiguous \
+                       # N: Revealed type is "builtins.int"
 [builtins fixtures/enum.pyi]
 
 [case testEnumFlag]
@@ -1421,6 +1422,53 @@ class Comparator(enum.Enum):
 reveal_type(Comparator.__foo__)  # N: Revealed type is "builtins.dict[builtins.str, builtins.int]"
 [builtins fixtures/dict.pyi]
 
+[case testEnumClassAttributeUnannotated]
+import enum
+from typing import ClassVar, Literal
+
+class MyEnum(enum.Enum):
+    foo: ClassVar[str]
+    bar: str
+
+    VALUE_A = 1
+    VALUE_B = 2
+
+reveal_type(MyEnum.foo)  # N: Revealed type is "builtins.str"
+reveal_type(MyEnum.bar)  # N: Revealed type is "builtins.str"
+x: Literal[MyEnum.foo]  # E: Parameter 1 of Literal[...] is invalid
+y: Literal[MyEnum.bar]  # E: Parameter 1 of Literal[...] is invalid
+[builtins fixtures/enum.pyi]
+
+[case testEnumAttributesInheritedFromMixin]
+from enum import Enum
+from typing import TYPE_CHECKING, ClassVar, Final, Literal
+
+class A:
+    var1 = 1
+    var2: ClassVar[str]
+    var3: Final[int] = 3
+    var4: str
+
+class E(A, Enum):
+    mem = 1
+
+reveal_type(E.var1)  # N: Revealed type is "builtins.int"
+reveal_type(E.var2)  # N: Revealed type is "builtins.str"
+reveal_type(E.var3)  # N: Revealed type is "builtins.int"
+reveal_type(E.var4)  # N: Revealed type is "builtins.str"
+reveal_type(E.mem)  # N: Revealed type is "Literal[__main__.E.mem]?"
+
+E.var1.value  # E: "int" has no attribute "value"
+E.var2.name  # E: "str" has no attribute "name"
+E.mem.name
+
+x1: Literal[E.var1]  # E: Parameter 1 of Literal[...] is invalid
+x2: Literal[E.var2]  # E: Parameter 1 of Literal[...] is invalid
+x3: Literal[E.var3]  # E: Parameter 1 of Literal[...] is invalid
+x4: Literal[E.var4]  # E: Parameter 1 of Literal[...] is invalid
+m: Literal[E.mem]
+[builtins fixtures/enum.pyi]
+
 [case testEnumWithInstanceAttributes]
 from enum import Enum
 class Foo(Enum):