Fix enum with property match type exhaustion

mypy/typeops.py

@@ -878,18 +878,10 @@ class Status(Enum):
         return make_simplified_union(items, contract_literals=False)
     elif isinstance(typ, Instance) and typ.type.fullname == target_fullname:
         if typ.type.is_enum:
-            new_items = []
-            for name, symbol in typ.type.names.items():
-                if not isinstance(symbol.node, Var):
-                    continue
-                # Skip these since Enum will remove it
-                if name in ENUM_REMOVED_PROPS:
-                    continue
-                # Skip private attributes
-                if name.startswith("__"):
-                    continue
-                new_items.append(LiteralType(name, typ))
-            return make_simplified_union(new_items, contract_literals=False)
+            return make_simplified_union(
+                [LiteralType(name, typ) for name in typ.get_enum_values()],
+                contract_literals=False,
+            )
         elif typ.type.fullname == "builtins.bool":
             return make_simplified_union(
                 [LiteralType(True, typ), LiteralType(False, typ)], contract_literals=False

mypy/types.py

@@ -1496,7 +1496,13 @@ def is_singleton_type(self) -> bool:
     def get_enum_values(self) -> list[str]:
         """Return the list of values for an Enum."""
         return [
-            name for name, sym in self.type.names.items() if isinstance(sym.node, mypy.nodes.Var)
+            name for name, sym in self.type.names.items()
+            if (
+                isinstance(sym.node, mypy.nodes.Var)
+                and name not in ENUM_REMOVED_PROPS
+                and not name.startswith("__")
+                and sym.node.has_explicit_value
+            )
         ]
 
 

test-data/unit/check-python310.test

@@ -1484,6 +1484,42 @@ def g(m: Medal) -> int:
             reveal_type(m)  # N: Revealed type is "Literal[__main__.Medal.bronze]"
             return 2
 
+
+[case testMatchLiteralPatternEnumWithProperty]
+from enum import Enum
+from typing import NoReturn
+def assert_never(x: NoReturn) -> None: ...
+
+class int:
+    def __new__(cls, value: int): pass
+
+class Medal(int, Enum):
+    prize: str
+
+    def __new__(cls, value: int, prize: str) -> Medal:
+        enum = int.__new__(cls, value)
+        enum._value_ = value
+        enum.prize = prize
+        return enum
+
+    gold = (1, 'cash prize')
+    silver = (2, 'sponsorship')
+    bronze = (3, 'nothing')
+
+m: Medal
+
+match m:
+    case Medal.gold:
+        reveal_type(m)  # N: Revealed type is "Literal[__main__.Medal.gold]"
+    case Medal.silver:
+        reveal_type(m)  # N: Revealed type is "Literal[__main__.Medal.silver]"
+    case Medal.bronze:
+        reveal_type(m)  # N: Revealed type is "Literal[__main__.Medal.bronze]"
+    case _ as unreachable:
+        assert_never(unreachable)
+
+[builtins fixtures/tuple.pyi]
+
 [case testMatchLiteralPatternEnumCustomEquals-skip]
 from enum import Enum
 class Medal(Enum):