test-data/unit/check-enum.test

-- This test file checks Enum

[case testEnumBasics]
from enum import Enum
class Medal(Enum):
    gold = 1
    silver = 2
    bronze = 3
reveal_type(Medal.bronze)  # N: Revealed type is "Literal[__main__.Medal.bronze]?"
m = Medal.gold
if int():
    m = 1  # E: Incompatible types in assignment (expression has type "int", variable has type "Medal")

[builtins fixtures/enum.pyi]

-- Creation from Enum call
-- -----------------------

[case testEnumCreatedFromStringLiteral]
from enum import Enum
from typing import Literal

x: Literal['ANT BEE CAT DOG'] = 'ANT BEE CAT DOG'
Animal = Enum('Animal', x)
reveal_type(Animal.ANT)  # N: Revealed type is "Literal[__main__.Animal.ANT]?"
reveal_type(Animal.BEE)  # N: Revealed type is "Literal[__main__.Animal.BEE]?"
reveal_type(Animal.CAT)  # N: Revealed type is "Literal[__main__.Animal.CAT]?"
reveal_type(Animal.DOG)  # N: Revealed type is "Literal[__main__.Animal.DOG]?"

[builtins fixtures/tuple.pyi]

[case testEnumCreatedFromFinalValue]
from enum import Enum
from typing import Final

x: Final['str'] = 'ANT BEE CAT DOG'
Animal = Enum('Animal', x)
reveal_type(Animal.ANT)  # N: Revealed type is "Literal[__main__.Animal.ANT]?"
reveal_type(Animal.BEE)  # N: Revealed type is "Literal[__main__.Animal.BEE]?"
reveal_type(Animal.CAT)  # N: Revealed type is "Literal[__main__.Animal.CAT]?"
reveal_type(Animal.DOG)  # N: Revealed type is "Literal[__main__.Animal.DOG]?"

[builtins fixtures/tuple.pyi]

-- Creation from EnumMeta
-- ----------------------

[case testEnumFromEnumMetaBasics]
from enum import EnumMeta
class Medal(metaclass=EnumMeta):
    gold = 1
    silver = "hello"
    bronze = None
    # Without __init__ the definition fails at runtime, but we want to verify that mypy
    # uses `enum.EnumMeta` and not `enum.Enum` as the definition of what is enum.
    def __init__(self, *args): pass
reveal_type(Medal.bronze)  # N: Revealed type is "Literal[__main__.Medal.bronze]?"
m = Medal.gold
if int():
    m = 1  # E: Incompatible types in assignment (expression has type "int", variable has type "Medal")
[builtins fixtures/tuple.pyi]

[case testEnumFromEnumMetaSubclass]
from enum import EnumMeta
class Achievement(metaclass=EnumMeta): pass
class Medal(Achievement):
    gold = 1
    silver = "hello"
    bronze = None
    # See comment in testEnumFromEnumMetaBasics
    def __init__(self, *args): pass
reveal_type(Medal.bronze)  # N: Revealed type is "Literal[__main__.Medal.bronze]?"
m = Medal.gold
if int():
    m = 1  # E: Incompatible types in assignment (expression has type "int", variable has type "Medal")
[builtins fixtures/tuple.pyi]

[case testEnumFromEnumMetaGeneric]
from enum import EnumMeta
from typing import Generic, TypeVar
T = TypeVar("T")
class Medal(Generic[T], metaclass=EnumMeta):  # E: Enum class cannot be generic
    q = None
[builtins fixtures/enum.pyi]

[case testEnumNameAndValue]
from enum import Enum
class Truth(Enum):
    true = True
    false = False
x = ''
x = Truth.true.name
reveal_type(Truth.true.name)    # N: Revealed type is "Literal['true']?"
reveal_type(Truth.false.value)  # N: Revealed type is "Literal[False]?"
[builtins fixtures/bool.pyi]

[case testEnumValueExtended]
from enum import Enum
class Truth(Enum):
    true = True
    false = False

def infer_truth(truth: Truth) -> None:
    reveal_type(truth.value) # N: Revealed type is "Literal[True]? | Literal[False]?"
[builtins fixtures/bool.pyi]

[case testEnumValueAllAuto]
from enum import Enum, auto
class Truth(Enum):
    true = auto()
    false = auto()

def infer_truth(truth: Truth) -> None:
    reveal_type(truth.value) # N: Revealed type is "builtins.int"
[builtins fixtures/primitives.pyi]

[case testEnumValueSomeAuto]
from enum import Enum, auto
class Truth(Enum):
    true = 8675309
    false = auto()

def infer_truth(truth: Truth) -> None:
    reveal_type(truth.value) # N: Revealed type is "builtins.int"
[builtins fixtures/primitives.pyi]

[case testEnumValueExtraMethods]
from enum import Enum
class Truth(Enum):
    true = True
    false = False

    def foo(self) -> str:
        return 'bar'

def infer_truth(truth: Truth) -> None:
    reveal_type(truth.value) # N: Revealed type is "Literal[True]? | Literal[False]?"
[builtins fixtures/bool.pyi]

[case testEnumValueCustomAuto]
from enum import Enum, auto
class AutoName(Enum):

    # In `typeshed`, this is a staticmethod and has more arguments,
    # but I have lied a bit to keep the test stubs lean.
    def _generate_next_value_(self) -> str:
        return "name"

class Truth(AutoName):
    true = auto()
    false = auto()

def infer_truth(truth: Truth) -> None:
    reveal_type(truth.value) # N: Revealed type is "builtins.str"
[builtins fixtures/primitives.pyi]

[case testEnumValueInhomogeneous]
from enum import Enum
class Truth(Enum):
    true = 'True'
    false = 0

def cannot_infer_truth(truth: Truth) -> None:
    reveal_type(truth.value) # N: Revealed type is "Any"
[builtins fixtures/bool.pyi]

[case testEnumValueSameType]
from enum import Enum

def newbool() -> bool:
    ...

class Truth(Enum):
    true = newbool()
    false = newbool()

def infer_truth(truth: Truth) -> None:
    reveal_type(truth.value) # N: Revealed type is "builtins.bool"
[builtins fixtures/bool.pyi]

[case testEnumTruthyness]
# mypy: warn-unreachable
import enum
from typing import Literal

class E(enum.Enum):
    zero = 0
    one = 1

def print(s: str) -> None: ...

if E.zero:
    print("zero is true")
if not E.zero:
    print("zero is false")  # E: Statement is unreachable

if E.one:
    print("one is true")
if not E.one:
    print("one is false")  # E: Statement is unreachable

def main(zero: Literal[E.zero], one: Literal[E.one]) -> None:
    if zero:
        print("zero is true")
    if not zero:
        print("zero is false")  # E: Statement is unreachable
    if one:
        print("one is true")
    if not one:
        print("one is false")  # E: Statement is unreachable
[builtins fixtures/tuple.pyi]

[case testEnumTruthynessCustomDunderBool]
# mypy: warn-unreachable
import enum
from typing import Literal

class E(enum.Enum):
    zero = 0
    one = 1
    def __bool__(self) -> Literal[False]:
        return False

def print(s: str) -> None: ...

if E.zero:
    print("zero is true")  # E: Statement is unreachable
if not E.zero:
    print("zero is false")

if E.one:
    print("one is true")  # E: Statement is unreachable
if not E.one:
    print("one is false")

def main(zero: Literal[E.zero], one: Literal[E.one]) -> None:
    if zero:
        print("zero is true")  # E: Statement is unreachable
    if not zero:
        print("zero is false")
    if one:
        print("one is true")  # E: Statement is unreachable
    if not one:
        print("one is false")
[builtins fixtures/enum.pyi]

[case testEnumTruthynessStrEnum]
# mypy: warn-unreachable
import enum
from typing import Literal

class E(enum.StrEnum):
    empty = ""
    not_empty = "asdf"

def print(s: str) -> None: ...

if E.empty:
    print("empty is true")
if not E.empty:
    print("empty is false")

if E.not_empty:
    print("not_empty is true")
if not E.not_empty:
    print("not_empty is false")

def main(empty: Literal[E.empty], not_empty: Literal[E.not_empty]) -> None:
    if empty:
        print("empty is true")
    if not empty:
        print("empty is false")
    if not_empty:
        print("not_empty is true")
    if not not_empty:
        print("not_empty is false")
[builtins fixtures/enum.pyi]

[case testEnumUnique]
import enum
@enum.unique
class E(enum.Enum):
    x = 1
    y = 1  # NOTE: This duplicate value is not detected by mypy at the moment
x = 1
x = E.x
[builtins fixtures/enum.pyi]
[out]
main:7: error: Incompatible types in assignment (expression has type "E", variable has type "int")

[case testIntEnum_assignToIntVariable]
from enum import IntEnum
class N(IntEnum):
    x = 1
    y = 1
n = 1
if int():
    n = N.x  # Subclass of int, so it's okay
s = ''
if int():
    s = N.y # E: Incompatible types in assignment (expression has type "N", variable has type "str")
[builtins fixtures/enum.pyi]

[case testIntEnum_functionTakingIntEnum]
from enum import IntEnum
class SomeIntEnum(IntEnum):
    x = 1
def takes_some_int_enum(n: SomeIntEnum):
    pass
takes_some_int_enum(SomeIntEnum.x)
takes_some_int_enum(1)  # Error
takes_some_int_enum(SomeIntEnum(1))  # How to deal with the above
[builtins fixtures/enum.pyi]
[out]
main:7: error: Argument 1 to "takes_some_int_enum" has incompatible type "int"; expected "SomeIntEnum"

[case testIntEnum_functionTakingInt]
from enum import IntEnum
class SomeIntEnum(IntEnum):
    x = 1
def takes_int(i: int):
    pass
takes_int(SomeIntEnum.x)
takes_int(2)
[builtins fixtures/enum.pyi]

[case testIntEnum_functionReturningIntEnum]
from enum import IntEnum
class SomeIntEnum(IntEnum):
    x = 1
def returns_some_int_enum() -> SomeIntEnum:
    return SomeIntEnum.x
an_int = 1
an_int = returns_some_int_enum()

an_enum = SomeIntEnum.x
an_enum = returns_some_int_enum()
[builtins fixtures/enum.pyi]
[out]

[case testStrEnumCreation]
# flags: --python-version 3.11
from enum import StrEnum

class MyStrEnum(StrEnum):
    x = 'x'
    y = 'y'

reveal_type(MyStrEnum.x)  # N: Revealed type is "Literal[__main__.MyStrEnum.x]?"
reveal_type(MyStrEnum.x.value)  # N: Revealed type is "Literal['x']?"
reveal_type(MyStrEnum.y)  # N: Revealed type is "Literal[__main__.MyStrEnum.y]?"
reveal_type(MyStrEnum.y.value)  # N: Revealed type is "Literal['y']?"
[builtins fixtures/enum.pyi]
[out]

[case testEnumMethods]
from enum import Enum

class Color(Enum):
    red = 1
    green = 2

    def m(self, x: int): pass
    @staticmethod
    def m2(x: int): pass

Color.red.m('')
Color.m2('')
[builtins fixtures/staticmethod.pyi]
[out]
main:11: error: Argument 1 to "m" of "Color" has incompatible type "str"; expected "int"
main:12: error: Argument 1 to "m2" of "Color" has incompatible type "str"; expected "int"

[case testIntEnum_ExtendedIntEnum_functionTakingExtendedIntEnum]
from enum import IntEnum
class ExtendedIntEnum(IntEnum):
    pass
class SomeExtIntEnum(ExtendedIntEnum):
    x = 1

def takes_int(i: int):
    pass
takes_int(SomeExtIntEnum.x)

def takes_some_ext_int_enum(s: SomeExtIntEnum):
    pass
takes_some_ext_int_enum(SomeExtIntEnum.x)
[builtins fixtures/enum.pyi]

[case testNamedTupleEnum]
from typing import NamedTuple
from enum import Enum

N = NamedTuple('N', [('bar', int)])

class E(N, Enum):
    X = N(1)

def f(x: E) -> None: pass

f(E.X)
[builtins fixtures/tuple.pyi]

[case testEnumCall]
from enum import IntEnum
class E(IntEnum):
    a = 1
x: int
reveal_type(E(x))
[builtins fixtures/tuple.pyi]
[out]
main:5: note: Revealed type is "__main__.E"

[case testEnumIndex]
from enum import IntEnum
class E(IntEnum):
    a = 1
s: str
reveal_type(E[s])
[builtins fixtures/enum.pyi]
[out]
main:5: note: Revealed type is "__main__.E"

[case testEnumIndexError]
from enum import IntEnum
class E(IntEnum):
    a = 1
E[1]  # E: Enum index should be a string (actual index type "int")
x = E[1]  # E: Enum index should be a string (actual index type "int")
[builtins fixtures/enum.pyi]

[case testEnumIndexIsNotAnAlias]
from enum import Enum

class E(Enum):
    a = 1
    b = 2
reveal_type(E['a'])  # N: Revealed type is "__main__.E"
E['a']
x = E['a']
reveal_type(x)  # N: Revealed type is "__main__.E"

def get_member(name: str) -> E:
    val = E[name]
    return val

reveal_type(get_member('a'))  # N: Revealed type is "__main__.E"
[builtins fixtures/enum.pyi]

[case testGenericEnum]
from enum import Enum
from typing import Generic, TypeVar

T = TypeVar('T')

class F(Generic[T], Enum):  # E: Enum class cannot be generic
    x: T
    y: T

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]
from enum import Flag
class C(Flag):
    a = 1
    b = 2
x = C.a
if int():
    x = 1 # E: Incompatible types in assignment (expression has type "int", variable has type "C")
if int():
    x = x | C.b
[builtins fixtures/enum.pyi]

[case testEnumIntFlag]
from enum import IntFlag
class C(IntFlag):
    a = 1
    b = 2
x = C.a
if int():
    x = 1 # E: Incompatible types in assignment (expression has type "int", variable has type "C")
if int():
    x = x | C.b
[builtins fixtures/enum.pyi]

[case testAnonymousEnum]
from enum import Enum
class A:
    def f(self) -> None:
        class E(Enum):
            a = 1
        self.x = E.a
a = A()
reveal_type(a.x)
[builtins fixtures/enum.pyi]
[out]
main:8: note: Revealed type is "__main__.E@4"

[case testEnumInClassBody]
from enum import Enum
class A:
    class E(Enum):
        a = 1
class B:
    class E(Enum):
        a = 1
x = A.E.a
y = B.E.a
if int():
    x = y # E: Incompatible types in assignment (expression has type "__main__.B.E", variable has type "__main__.A.E")
[builtins fixtures/enum.pyi]

[case testFunctionalEnumString]
from enum import Enum, IntEnum
E = Enum('E', 'foo bar')
I = IntEnum('I', ' bar, baz ')
reveal_type(E.foo)
reveal_type(E.bar.value)
reveal_type(I.bar)
reveal_type(I.baz.value)
[builtins fixtures/enum.pyi]
[out]
main:4: note: Revealed type is "Literal[__main__.E.foo]?"
main:5: note: Revealed type is "Any"
main:6: note: Revealed type is "Literal[__main__.I.bar]?"
main:7: note: Revealed type is "builtins.int"

[case testFunctionalEnumListOfStrings]
from enum import Enum, IntEnum
E = Enum('E', ('foo', 'bar'))
F = IntEnum('F', ['bar', 'baz'])
reveal_type(E.foo)
reveal_type(F.baz)
[builtins fixtures/enum.pyi]
[out]
main:4: note: Revealed type is "Literal[__main__.E.foo]?"
main:5: note: Revealed type is "Literal[__main__.F.baz]?"

[case testFunctionalEnumListOfPairs]
from enum import Enum, IntEnum
E = Enum('E', [('foo', 1), ['bar', 2]])
F = IntEnum('F', (['bar', 1], ('baz', 2)))
reveal_type(E.foo)
reveal_type(F.baz)
reveal_type(E.foo.value)
reveal_type(F.bar.name)
[builtins fixtures/enum.pyi]
[out]
main:4: note: Revealed type is "Literal[__main__.E.foo]?"
main:5: note: Revealed type is "Literal[__main__.F.baz]?"
main:6: note: Revealed type is "Literal[1]?"
main:7: note: Revealed type is "Literal['bar']?"

[case testFunctionalEnumDict]
from enum import Enum, IntEnum
E = Enum('E', {'foo': 1, 'bar': 2})
F = IntEnum('F', {'bar': 1, 'baz': 2})
reveal_type(E.foo)
reveal_type(F.baz)
reveal_type(E.foo.value)
reveal_type(F.bar.name)
[builtins fixtures/enum.pyi]
[out]
main:4: note: Revealed type is "Literal[__main__.E.foo]?"
main:5: note: Revealed type is "Literal[__main__.F.baz]?"
main:6: note: Revealed type is "Literal[1]?"
main:7: note: Revealed type is "Literal['bar']?"


[case testEnumKeywordsArgs]
from enum import Enum, IntEnum

PictureSize = Enum('PictureSize', 'P0 P1 P2 P3 P4 P5 P6 P7 P8', type=str, module=__name__)
fake_enum1 = Enum('fake_enum1', ['a', 'b'])
fake_enum2 = Enum('fake_enum2', names=['a', 'b'])
fake_enum3 = Enum(value='fake_enum3', names=['a', 'b'])
fake_enum4 = Enum(value='fake_enum4', names=['a', 'b'] , module=__name__)
[builtins fixtures/enum.pyi]

[case testFunctionalEnumErrors]
from enum import Enum, IntEnum
A = Enum('A')  # E: Too few arguments for Enum()
B = Enum('B', 42)  # E: Second argument of Enum() must be string, tuple, list or dict literal for mypy to determine Enum members
C = Enum('C', 'a b', 'x', 'y', 'z', 'p', 'q')  # E: Too many arguments for Enum()
D = Enum('D', foo)  # E: Second argument of Enum() must be string, tuple, list or dict literal for mypy to determine Enum members \
                    # E: Name "foo" is not defined
bar = 'x y z'
E = Enum('E', bar)  # E: Second argument of Enum() must be string, tuple, list or dict literal for mypy to determine Enum members
I = IntEnum('I')  # E: Too few arguments for IntEnum()
J = IntEnum('I', 42)  # E: Second argument of IntEnum() must be string, tuple, list or dict literal for mypy to determine Enum members
K = IntEnum('I', 'p q', 'x', 'y', 'z', 'p', 'q')  # E: Too many arguments for IntEnum()
L = Enum('L', ' ')  # E: Enum() needs at least one item
M = Enum('M', ())  # E: Enum() needs at least one item
N = IntEnum('M', [])  # E: IntEnum() needs at least one item
P = Enum('P', [42])  # E: Enum() with tuple or list expects strings or (name, value) pairs
Q = Enum('Q', [('a', 42, 0)])  # E: Enum() with tuple or list expects strings or (name, value) pairs
R = IntEnum('R', [[0, 42]])  # E: IntEnum() with tuple or list expects strings or (name, value) pairs
S = Enum('S', {1: 1})  # E: Enum() with dict literal requires string literals
T = Enum('T', keyword='a b')  # E: Unexpected keyword argument "keyword"
U = Enum('U', *['a'])  # E: Unexpected arguments to Enum()
V = Enum('U', **{'a': 1})  # E: Unexpected arguments to Enum()
W = Enum('W', 'a b')
W.c  # E: "type[W]" has no attribute "c"
X = Enum('Something', 'a b')  # E: String argument 1 "Something" to enum.Enum(...) does not match variable name "X"
reveal_type(X.a)  # N: Revealed type is "Literal[__main__.X.a]?"
X.asdf  # E: "type[X]" has no attribute "asdf"


[builtins fixtures/tuple.pyi]
[typing fixtures/typing-medium.pyi]

[case testFunctionalEnumFlag]
from enum import Flag, IntFlag
A = Flag('A', 'x y')
B = IntFlag('B', 'a b')
reveal_type(A.x)        # N: Revealed type is "Literal[__main__.A.x]?"
reveal_type(B.a)        # N: Revealed type is "Literal[__main__.B.a]?"
reveal_type(A.x.name)   # N: Revealed type is "Literal['x']?"
reveal_type(B.a.name)   # N: Revealed type is "Literal['a']?"

reveal_type(A.x.value)  # N: Revealed type is "builtins.int"
reveal_type(B.a.value)  # N: Revealed type is "builtins.int"
[builtins fixtures/enum.pyi]

[case testAnonymousFunctionalEnum]
from enum import Enum
class A:
    def f(self) -> None:
        E = Enum('E', 'a b')
        self.x = E.a
a = A()
reveal_type(a.x)
[builtins fixtures/enum.pyi]
[out]
main:7: note: Revealed type is "__main__.E@4"

[case testFunctionalEnumInClassBody]
from enum import Enum
class A:
    E = Enum('E', 'a b')
class B:
    E = Enum('E', 'a b')
x = A.E.a
y = B.E.a
if int():
    x = y # E: Incompatible types in assignment (expression has type "__main__.B.E", variable has type "__main__.A.E")
[builtins fixtures/enum.pyi]

[case testFunctionalEnumProtocols]
from enum import IntEnum
Color = IntEnum('Color', 'red green blue')
reveal_type(Color['green'])  # N: Revealed type is "__main__.Color"
for c in Color:
    reveal_type(c)  # N: Revealed type is "__main__.Color"
reveal_type(list(Color))  # N: Revealed type is "builtins.list[__main__.Color]"

[builtins fixtures/list.pyi]

[case testEnumWorkWithForward]
from enum import Enum
a: E = E.x  # type: ignore[used-before-def]
class E(Enum):
    x = 1
    y = 2
[builtins fixtures/enum.pyi]
[out]

[case testEnumWorkWithForward2]
from enum import Enum
b: F
F = Enum('F', {'x': 1, 'y': 2})

def fn(x: F) -> None:
    pass
fn(b)
[builtins fixtures/enum.pyi]
[out]

[case testFunctionalEnum]
# TODO: Needs to have enum34 stubs somehow
from enum import Enum
Eu = Enum(u'Eu', u'a b')
Eb = Enum(b'Eb', b'a b')  # E: Enum() expects a string literal as the first argument
Gu = Enum(u'Gu', {u'a': 1})
Gb = Enum(b'Gb', {b'a': 1})  # E: Enum() expects a string literal as the first argument
Hu = Enum(u'Hu', [u'a'])
Hb = Enum(b'Hb', [b'a'])  # E: Enum() expects a string literal as the first argument
Eu.a
Eb.a
Gu.a
Gb.a
Hu.a
Hb.a
[builtins fixtures/enum.pyi]
[out]

[case testEnumIncremental]
import m
reveal_type(m.E.a)
reveal_type(m.F.b)
[file m.py]
from enum import Enum
class E(Enum):
    a = 1
    b = 2
F = Enum('F', 'a b')
[builtins fixtures/enum.pyi]
[rechecked]
[stale]
[out1]
main:2: note: Revealed type is "Literal[m.E.a]?"
main:3: note: Revealed type is "Literal[m.F.b]?"
[out2]
main:2: note: Revealed type is "Literal[m.E.a]?"
main:3: note: Revealed type is "Literal[m.F.b]?"

[case testEnumAuto]
from enum import Enum, auto
class Test(Enum):
    a = auto()
    b = auto()

reveal_type(Test.a)  # N: Revealed type is "Literal[__main__.Test.a]?"
[builtins fixtures/primitives.pyi]

[case testEnumAttributeAccessMatrix]
from enum import Enum, IntEnum, IntFlag, Flag, EnumMeta, auto
from typing import Literal

def is_x(val: Literal['x']) -> None: pass

A1 = Enum('A1', 'x')
class A2(Enum):
    x = auto()
class A3(Enum):
    x = 1

is_x(reveal_type(A1.x.name))    # N: Revealed type is "Literal['x']"
is_x(reveal_type(A1.x._name_))  # N: Revealed type is "Literal['x']"
reveal_type(A1.x.value)         # N: Revealed type is "Any"
reveal_type(A1.x._value_)       # N: Revealed type is "Any"
is_x(reveal_type(A2.x.name))    # N: Revealed type is "Literal['x']"
is_x(reveal_type(A2.x._name_))  # N: Revealed type is "Literal['x']"
reveal_type(A2.x.value)         # N: Revealed type is "builtins.int"
reveal_type(A2.x._value_)       # N: Revealed type is "builtins.int"
is_x(reveal_type(A3.x.name))    # N: Revealed type is "Literal['x']"
is_x(reveal_type(A3.x._name_))  # N: Revealed type is "Literal['x']"
reveal_type(A3.x.value)         # N: Revealed type is "Literal[1]?"
reveal_type(A3.x._value_)       # N: Revealed type is "Literal[1]?"

B1 = IntEnum('B1', 'x')
class B2(IntEnum):
    x = auto()
class B3(IntEnum):
    x = 1

is_x(reveal_type(B1.x.name))    # N: Revealed type is "Literal['x']"
is_x(reveal_type(B1.x._name_))  # N: Revealed type is "Literal['x']"
reveal_type(B1.x.value)         # N: Revealed type is "builtins.int"
reveal_type(B1.x._value_)       # N: Revealed type is "builtins.int"
is_x(reveal_type(B2.x.name))    # N: Revealed type is "Literal['x']"
is_x(reveal_type(B2.x._name_))  # N: Revealed type is "Literal['x']"
reveal_type(B2.x.value)         # N: Revealed type is "builtins.int"
reveal_type(B2.x._value_)       # N: Revealed type is "builtins.int"
is_x(reveal_type(B3.x.name))    # N: Revealed type is "Literal['x']"
is_x(reveal_type(B3.x._name_))  # N: Revealed type is "Literal['x']"
reveal_type(B3.x.value)         # N: Revealed type is "Literal[1]?"
reveal_type(B3.x._value_)       # N: Revealed type is "Literal[1]?"

C1 = IntFlag('C1', 'x')
class C2(IntFlag):
    x = auto()
class C3(IntFlag):
    x = 1

is_x(reveal_type(C1.x.name))    # N: Revealed type is "Literal['x']"
is_x(reveal_type(C1.x._name_))  # N: Revealed type is "Literal['x']"
reveal_type(C1.x.value)         # N: Revealed type is "builtins.int"
reveal_type(C1.x._value_)       # N: Revealed type is "builtins.int"
is_x(reveal_type(C2.x.name))    # N: Revealed type is "Literal['x']"
is_x(reveal_type(C2.x._name_))  # N: Revealed type is "Literal['x']"
reveal_type(C2.x.value)         # N: Revealed type is "builtins.int"
reveal_type(C2.x._value_)       # N: Revealed type is "builtins.int"
is_x(reveal_type(C3.x.name))    # N: Revealed type is "Literal['x']"
is_x(reveal_type(C3.x._name_))  # N: Revealed type is "Literal['x']"
reveal_type(C3.x.value)         # N: Revealed type is "Literal[1]?"
reveal_type(C3.x._value_)       # N: Revealed type is "Literal[1]?"

D1 = Flag('D1', 'x')
class D2(Flag):
    x = auto()
class D3(Flag):
    x = 1

is_x(reveal_type(D1.x.name))    # N: Revealed type is "Literal['x']"
is_x(reveal_type(D1.x._name_))  # N: Revealed type is "Literal['x']"
reveal_type(D1.x.value)         # N: Revealed type is "builtins.int"
reveal_type(D1.x._value_)       # N: Revealed type is "builtins.int"
is_x(reveal_type(D2.x.name))    # N: Revealed type is "Literal['x']"
is_x(reveal_type(D2.x._name_))  # N: Revealed type is "Literal['x']"
reveal_type(D2.x.value)         # N: Revealed type is "builtins.int"
reveal_type(D2.x._value_)       # N: Revealed type is "builtins.int"
is_x(reveal_type(D3.x.name))    # N: Revealed type is "Literal['x']"
is_x(reveal_type(D3.x._name_))  # N: Revealed type is "Literal['x']"
reveal_type(D3.x.value)         # N: Revealed type is "Literal[1]?"
reveal_type(D3.x._value_)       # N: Revealed type is "Literal[1]?"

# TODO: Generalize our enum functional API logic to work with subclasses of Enum
# See https://github.com/python/mypy/issues/6037

class Parent(Enum): pass
# E1 = Parent('E1', 'x')  # See above TODO
class E2(Parent):
    x = auto()
class E3(Parent):
    x = 1

is_x(reveal_type(E2.x.name))    # N: Revealed type is "Literal['x']"
is_x(reveal_type(E2.x._name_))  # N: Revealed type is "Literal['x']"
reveal_type(E2.x.value)         # N: Revealed type is "builtins.int"
reveal_type(E2.x._value_)       # N: Revealed type is "builtins.int"
is_x(reveal_type(E3.x.name))    # N: Revealed type is "Literal['x']"
is_x(reveal_type(E3.x._name_))  # N: Revealed type is "Literal['x']"
reveal_type(E3.x.value)         # N: Revealed type is "Literal[1]?"
reveal_type(E3.x._value_)       # N: Revealed type is "Literal[1]?"


# TODO: Figure out if we can construct enums using EnumMetas using the functional API.
# Also figure out if we even care about supporting that use case.
class F2(metaclass=EnumMeta):
    x = auto()
class F3(metaclass=EnumMeta):
    x = 1

F2.x.name      # E: "F2" has no attribute "name"
F2.x._name_    # E: "F2" has no attribute "_name_"
F2.x.value     # E: "F2" has no attribute "value"
F2.x._value_   # E: "F2" has no attribute "_value_"
F3.x.name      # E: "F3" has no attribute "name"
F3.x._name_    # E: "F3" has no attribute "_name_"
F3.x.value     # E: "F3" has no attribute "value"
F3.x._value_   # E: "F3" has no attribute "_value_"
[builtins fixtures/primitives.pyi]

[case testEnumAttributeChangeIncremental]
from a import SomeEnum
reveal_type(SomeEnum.a.value)

[file a.py]
from b import SomeEnum

[file b.py]
from enum import Enum
class SomeEnum(Enum):
    a = 1

[file b.py.2]
from enum import Enum
class SomeEnum(Enum):
    a = "foo"
[builtins fixtures/enum.pyi]
[out]
main:2: note: Revealed type is "Literal[1]?"
[out2]
main:2: note: Revealed type is "Literal['foo']?"

[case testEnumReachabilityChecksBasic]
# flags: --warn-unreachable
from enum import Enum
from typing import Literal

class Foo(Enum):
    A = 1
    B = 2
    C = 3

x: Literal[Foo.A, Foo.B, Foo.C]
if x is Foo.A:
    reveal_type(x)  # N: Revealed type is "Literal[__main__.Foo.A]"
elif x is Foo.B:
    reveal_type(x)  # N: Revealed type is "Literal[__main__.Foo.B]"
elif x is Foo.C:
    reveal_type(x)  # N: Revealed type is "Literal[__main__.Foo.C]"
else:
    reveal_type(x)  # E: Statement is unreachable
reveal_type(x) # N: Revealed type is "Literal[__main__.Foo.A] | Literal[__main__.Foo.B] | Literal[__main__.Foo.C]"

if Foo.A is x:
    reveal_type(x)  # N: Revealed type is "Literal[__main__.Foo.A]"
elif Foo.B is x:
    reveal_type(x)  # N: Revealed type is "Literal[__main__.Foo.B]"
elif Foo.C is x:
    reveal_type(x)  # N: Revealed type is "Literal[__main__.Foo.C]"
else:
    reveal_type(x)  # E: Statement is unreachable
reveal_type(x) # N: Revealed type is "Literal[__main__.Foo.A] | Literal[__main__.Foo.B] | Literal[__main__.Foo.C]"

y: Foo
if y is Foo.A:
    reveal_type(y)  # N: Revealed type is "Literal[__main__.Foo.A]"
elif y is Foo.B:
    reveal_type(y)  # N: Revealed type is "Literal[__main__.Foo.B]"
elif y is Foo.C:
    reveal_type(y)  # N: Revealed type is "Literal[__main__.Foo.C]"
else:
    reveal_type(y)  # E: Statement is unreachable
reveal_type(y) # N: Revealed type is "__main__.Foo"

if Foo.A is y:
    reveal_type(y)  # N: Revealed type is "Literal[__main__.Foo.A]"
elif Foo.B is y:
    reveal_type(y)  # N: Revealed type is "Literal[__main__.Foo.B]"
elif Foo.C is y:
    reveal_type(y)  # N: Revealed type is "Literal[__main__.Foo.C]"
else:
    reveal_type(y)  # E: Statement is unreachable
reveal_type(y) # N: Revealed type is "__main__.Foo"
[builtins fixtures/bool.pyi]

[case testEnumReachabilityChecksWithOrdering]
# flags: --warn-unreachable
from enum import Enum
from typing import Literal

class Foo(Enum):
    _order_ = "A B"
    A = 1
    B = 2

Foo._order_  # E: "type[Foo]" has no attribute "_order_"

x: Literal[Foo.A, Foo.B]
if x is Foo.A:
    reveal_type(x)  # N: Revealed type is "Literal[__main__.Foo.A]"
elif x is Foo.B:
    reveal_type(x)  # N: Revealed type is "Literal[__main__.Foo.B]"
else:
    reveal_type(x)  # E: Statement is unreachable

class Bar(Enum):
    __order__ = "A B"
    A = 1
    B = 2

Bar.__order__  # E: "type[Bar]" has no attribute "__order__"

y: Literal[Bar.A, Bar.B]
if y is Bar.A:
    reveal_type(y)  # N: Revealed type is "Literal[__main__.Bar.A]"
elif y is Bar.B:
    reveal_type(y)  # N: Revealed type is "Literal[__main__.Bar.B]"
else:
    reveal_type(y)  # E: Statement is unreachable

x2: Foo
if x2 is Foo.A:
    reveal_type(x2)  # N: Revealed type is "Literal[__main__.Foo.A]"
elif x2 is Foo.B:
    reveal_type(x2)  # N: Revealed type is "Literal[__main__.Foo.B]"
else:
    reveal_type(x2)  # E: Statement is unreachable

y2: Bar
if y2 is Bar.A:
    reveal_type(y2)  # N: Revealed type is "Literal[__main__.Bar.A]"
elif y2 is Bar.B:
    reveal_type(y2)  # N: Revealed type is "Literal[__main__.Bar.B]"
else:
    reveal_type(y2)  # E: Statement is unreachable
[builtins fixtures/tuple.pyi]

[case testEnumReachabilityChecksIndirect]
# flags: --warn-unreachable
from enum import Enum
from typing import Final, Literal

class Foo(Enum):
    A = 1
    B = 2
    C = 3

def accepts_foo_a(x: Literal[Foo.A]) -> None: ...

x: Foo
y: Literal[Foo.A]
z: Final = Foo.A

if x is y:
    reveal_type(x)  # N: Revealed type is "Literal[__main__.Foo.A]"
    reveal_type(y)  # N: Revealed type is "Literal[__main__.Foo.A]"
else:
    reveal_type(x)  # N: Revealed type is "Literal[__main__.Foo.B] | Literal[__main__.Foo.C]"
    reveal_type(y)  # N: Revealed type is "Literal[__main__.Foo.A]"
reveal_type(x) # N: Revealed type is "__main__.Foo"
if y is x:
    reveal_type(x)  # N: Revealed type is "Literal[__main__.Foo.A]"
    reveal_type(y)  # N: Revealed type is "Literal[__main__.Foo.A]"
else:
    reveal_type(x)  # N: Revealed type is "Literal[__main__.Foo.B] | Literal[__main__.Foo.C]"
    reveal_type(y)  # N: Revealed type is "Literal[__main__.Foo.A]"
reveal_type(x) # N: Revealed type is "__main__.Foo"

if x is z:
    reveal_type(x)  # N: Revealed type is "Literal[__main__.Foo.A]"
    reveal_type(z)  # N: Revealed type is "Literal[__main__.Foo.A]?"
    accepts_foo_a(z)
else:
    reveal_type(x)  # N: Revealed type is "Literal[__main__.Foo.B] | Literal[__main__.Foo.C]"
    reveal_type(z)  # N: Revealed type is "Literal[__main__.Foo.A]?"
    accepts_foo_a(z)
reveal_type(x) # N: Revealed type is "__main__.Foo"
if z is x:
    reveal_type(x)  # N: Revealed type is "Literal[__main__.Foo.A]"
    reveal_type(z)  # N: Revealed type is "Literal[__main__.Foo.A]?"
    accepts_foo_a(z)
else:
    reveal_type(x)  # N: Revealed type is "Literal[__main__.Foo.B] | Literal[__main__.Foo.C]"
    reveal_type(z)  # N: Revealed type is "Literal[__main__.Foo.A]?"
    accepts_foo_a(z)
reveal_type(x) # N: Revealed type is "__main__.Foo"

if y is z:
    reveal_type(y)  # N: Revealed type is "Literal[__main__.Foo.A]"
    reveal_type(z)  # N: Revealed type is "Literal[__main__.Foo.A]?"
    accepts_foo_a(z)
else:
    reveal_type(y)  # E: Statement is unreachable
    reveal_type(z)
if z is y:
    reveal_type(y)  # N: Revealed type is "Literal[__main__.Foo.A]"
    reveal_type(z)  # N: Revealed type is "Literal[__main__.Foo.A]?"
    accepts_foo_a(z)
else:
    reveal_type(y)  # E: Statement is unreachable
    reveal_type(z)
[builtins fixtures/bool.pyi]

[case testEnumReachabilityNarrowingForUnionMessiness]
# flags: --warn-unreachable
from enum import Enum
from typing import Literal

class Foo(Enum):
    A = 1
    B = 2
    C = 3

x: Foo
y: Literal[Foo.A, Foo.B]
z: Literal[Foo.B, Foo.C]

if x is y:
    reveal_type(x)  # N: Revealed type is "Literal[__main__.Foo.A] | Literal[__main__.Foo.B]"
    reveal_type(y)  # N: Revealed type is "Literal[__main__.Foo.A] | Literal[__main__.Foo.B]"
else:
    reveal_type(x)  # N: Revealed type is "__main__.Foo"
    reveal_type(y)  # N: Revealed type is "Literal[__main__.Foo.A] | Literal[__main__.Foo.B]"

if y is z:
    reveal_type(y)  # N: Revealed type is "Literal[__main__.Foo.B]"
    reveal_type(z)  # N: Revealed type is "Literal[__main__.Foo.B]"
else:
    reveal_type(y)  # N: Revealed type is "Literal[__main__.Foo.A] | Literal[__main__.Foo.B]"
    reveal_type(z)  # N: Revealed type is "Literal[__main__.Foo.B] | Literal[__main__.Foo.C]"
[builtins fixtures/bool.pyi]

[case testEnumReachabilityWithNone]
# flags: --warn-unreachable
from enum import Enum
from typing import Optional

class Foo(Enum):
    A = 1
    B = 2
    C = 3

x: Optional[Foo]
if x:
    reveal_type(x)  # N: Revealed type is "__main__.Foo"
else:
    reveal_type(x)  # N: Revealed type is "None"

if x is not None:
    reveal_type(x)  # N: Revealed type is "__main__.Foo"
else:
    reveal_type(x)  # N: Revealed type is "None"

if x is Foo.A:
    reveal_type(x)  # N: Revealed type is "Literal[__main__.Foo.A]"
else:
    reveal_type(x)  # N: Revealed type is "Literal[__main__.Foo.B] | Literal[__main__.Foo.C] | None"
reveal_type(x) # N: Revealed type is "__main__.Foo | None"
[builtins fixtures/enum.pyi]

[case testEnumReachabilityWithMultipleEnums]
# flags: --warn-unreachable
from enum import Enum
from typing import Literal, Union

class Foo(Enum):
    A = 1
    B = 2
class Bar(Enum):
    A = 1
    B = 2

x1: Union[Foo, Bar]
if x1 is Foo.A:
    reveal_type(x1)  # N: Revealed type is "Literal[__main__.Foo.A]"
else:
    reveal_type(x1)  # N: Revealed type is "Literal[__main__.Foo.B] | __main__.Bar"
reveal_type(x1) # N: Revealed type is "__main__.Foo | __main__.Bar"

x2: Union[Foo, Bar]
if x2 is Bar.A:
    reveal_type(x2)  # N: Revealed type is "Literal[__main__.Bar.A]"
else:
    reveal_type(x2)  # N: Revealed type is "__main__.Foo | Literal[__main__.Bar.B]"
reveal_type(x2) # N: Revealed type is "__main__.Foo | __main__.Bar"

x3: Union[Foo, Bar]
if x3 is Foo.A or x3 is Bar.A:
    reveal_type(x3)  # N: Revealed type is "Literal[__main__.Foo.A] | Literal[__main__.Bar.A]"
else:
    reveal_type(x3)  # N: Revealed type is "Literal[__main__.Foo.B] | Literal[__main__.Bar.B]"
reveal_type(x3) # N: Revealed type is "__main__.Foo | __main__.Bar"

[builtins fixtures/bool.pyi]

[case testEnumReachabilityPEP484ExampleWithFinal]
# flags: --warn-unreachable
from typing import Final, Union
from enum import Enum

class Empty(Enum):
    token = 0
_empty: Final = Empty.token

def func(x: Union[int, None, Empty] = _empty) -> int:
    boom = x + 42       # E: Unsupported left operand type for + ("None") \
                        # E: Unsupported left operand type for + ("Empty") \
                        # N: Left operand is of type "int | Empty | None"
    if x is _empty:
        reveal_type(x)  # N: Revealed type is "Literal[__main__.Empty.token]"
        return 0
    elif x is None:
        reveal_type(x)  # N: Revealed type is "None"
        return 1
    else:  # At this point typechecker knows that x can only have type int
        reveal_type(x)  # N: Revealed type is "builtins.int"
        return x + 2
[builtins fixtures/primitives.pyi]

[case testEnumReachabilityPEP484ExampleWithMultipleValues]
# flags: --warn-unreachable
from typing import Union
from enum import Enum

class Reason(Enum):
    timeout = 1
    error = 2

def process(response: Union[str, Reason] = '') -> str:
    if response is Reason.timeout:
        reveal_type(response)  # N: Revealed type is "Literal[__main__.Reason.timeout]"
        return 'TIMEOUT'
    elif response is Reason.error:
        reveal_type(response)  # N: Revealed type is "Literal[__main__.Reason.error]"
        return 'ERROR'
    else:
        # response can be only str, all other possible values exhausted
        reveal_type(response)  # N: Revealed type is "builtins.str"
        return 'PROCESSED: ' + response
[builtins fixtures/primitives.pyi]


[case testEnumReachabilityPEP484ExampleSingleton]
# flags: --warn-unreachable
from typing import Final, Union
from enum import Enum

class Empty(Enum):
    token = 0
_empty = Empty.token

def func(x: Union[int, None, Empty] = _empty) -> int:
    boom = x + 42       # E: Unsupported left operand type for + ("None") \
                        # E: Unsupported left operand type for + ("Empty") \
                        # N: Left operand is of type "int | Empty | None"
    if x is _empty:
        reveal_type(x)  # N: Revealed type is "Literal[__main__.Empty.token]"
        return 0
    elif x is None:
        reveal_type(x)  # N: Revealed type is "None"
        return 1
    else:  # At this point typechecker knows that x can only have type int
        reveal_type(x)  # N: Revealed type is "builtins.int"
        return x + 2
[builtins fixtures/primitives.pyi]

[case testEnumReachabilityPEP484ExampleSingletonWithMethod]
# flags: --python-version 3.11 --warn-unreachable
from typing import Final, Union
from enum import Enum, member

class Empty(Enum):
    # note, that without `member` we cannot tell that `token` is a member:
    token = member(lambda x: x)

    def f(self) -> int:
        return 1

_empty = Empty.token
reveal_type(_empty)  # N: Revealed type is "__main__.Empty"
reveal_type(Empty.f) # N: Revealed type is "def (self: __main__.Empty) -> builtins.int"

def func(x: Union[int, None, Empty] = _empty) -> int:
    boom = x + 42       # E: Unsupported left operand type for + ("None") \
                        # E: Unsupported left operand type for + ("Empty") \
                        # N: Left operand is of type "int | Empty | None"
    if x is _empty:
        reveal_type(x)  # N: Revealed type is "Literal[__main__.Empty.token]"
        return 0
    elif x is None:
        reveal_type(x)  # N: Revealed type is "None"
        return 1
    else:  # At this point typechecker knows that x can only have type 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("b", [("foo", "bar")])  # E: Enum type as attribute is not supported

reveal_type(A().b)  # N: Revealed type is "Any"
[builtins fixtures/enum.pyi]

[case testEnumReachabilityWithChaining]
# flags: --warn-unreachable
from enum import Enum

class Foo(Enum):
    A = 1
    B = 2

x: Foo
y: Foo

# We can't narrow anything in the else cases -- what if
# x is Foo.A and y is Foo.B or vice versa, for example?
if x is y is Foo.A:
    reveal_type(x)   # N: Revealed type is "Literal[__main__.Foo.A]"
    reveal_type(y)   # N: Revealed type is "Literal[__main__.Foo.A]"
elif x is y is Foo.B:
    reveal_type(x)   # N: Revealed type is "Literal[__main__.Foo.B]"
    reveal_type(y)   # N: Revealed type is "Literal[__main__.Foo.B]"
else:
    reveal_type(x)   # N: Revealed type is "__main__.Foo"
    reveal_type(y)   # N: Revealed type is "__main__.Foo"
reveal_type(x)       # N: Revealed type is "__main__.Foo"
reveal_type(y)       # N: Revealed type is "__main__.Foo"

if x is Foo.A is y:
    reveal_type(x)   # N: Revealed type is "Literal[__main__.Foo.A]"
    reveal_type(y)   # N: Revealed type is "Literal[__main__.Foo.A]"
elif x is Foo.B is y:
    reveal_type(x)   # N: Revealed type is "Literal[__main__.Foo.B]"
    reveal_type(y)   # N: Revealed type is "Literal[__main__.Foo.B]"
else:
    reveal_type(x)   # N: Revealed type is "__main__.Foo"
    reveal_type(y)   # N: Revealed type is "__main__.Foo"
reveal_type(x)       # N: Revealed type is "__main__.Foo"
reveal_type(y)       # N: Revealed type is "__main__.Foo"

if Foo.A is x is y:
    reveal_type(x)   # N: Revealed type is "Literal[__main__.Foo.A]"
    reveal_type(y)   # N: Revealed type is "Literal[__main__.Foo.A]"
elif Foo.B is x is y:
    reveal_type(x)   # N: Revealed type is "Literal[__main__.Foo.B]"
    reveal_type(y)   # N: Revealed type is "Literal[__main__.Foo.B]"
else:
    reveal_type(x)   # N: Revealed type is "__main__.Foo"
    reveal_type(y)   # N: Revealed type is "__main__.Foo"
reveal_type(x)       # N: Revealed type is "__main__.Foo"
reveal_type(y)       # N: Revealed type is "__main__.Foo"

[builtins fixtures/primitives.pyi]

[case testEnumReachabilityWithChainingDisjoint]
# flags: --warn-unreachable
from enum import Enum

class Foo(Enum):
    A = 1
    B = 2

    # Used to divide up a chained comparison into multiple identity groups
    def __lt__(self, other: object) -> bool: return True

x: Foo
y: Foo

# No conflict
if x is Foo.A < y is Foo.B:
    reveal_type(x)  # N: Revealed type is "Literal[__main__.Foo.A]"
    reveal_type(y)  # N: Revealed type is "Literal[__main__.Foo.B]"
else:
    # Note: we can't narrow in this case. What if both x and y
    # are Foo.A, for example?
    reveal_type(x)  # N: Revealed type is "__main__.Foo"
    reveal_type(y)  # N: Revealed type is "__main__.Foo"
reveal_type(x)      # N: Revealed type is "__main__.Foo"
reveal_type(y)      # N: Revealed type is "__main__.Foo"

# The standard output when we end up inferring two disjoint facts about the same expr
if x is Foo.A and x is Foo.B:
    reveal_type(x)  # E: Statement is unreachable
else:
    reveal_type(x)  # N: Revealed type is "__main__.Foo"
reveal_type(x)      # N: Revealed type is "__main__.Foo"

# ..and we get the same result if we have two disjoint groups within the same comp expr
if x is Foo.A < x is Foo.B:
    reveal_type(x)  # E: Statement is unreachable
else:
    reveal_type(x)  # N: Revealed type is "__main__.Foo"
reveal_type(x)      # N: Revealed type is "__main__.Foo"
[builtins fixtures/primitives.pyi]

[case testEnumReachabilityWithChainingDirectConflict]
# flags: --warn-unreachable
from enum import Enum
from typing import Final, Literal

class Foo(Enum):
    A = 1
    B = 2
    C = 3

x: Foo
if x is Foo.A is Foo.B:
   reveal_type(x)   # E: Statement is unreachable
else:
   reveal_type(x)   # N: Revealed type is "__main__.Foo"
reveal_type(x)      # N: Revealed type is "__main__.Foo"

literal_a: Literal[Foo.A]
literal_b: Literal[Foo.B]
if x is literal_a is literal_b:
   reveal_type(x)   # E: Statement is unreachable
else:
   reveal_type(x)   # N: Revealed type is "__main__.Foo"
reveal_type(x)      # N: Revealed type is "__main__.Foo"

final_a: Final = Foo.A
final_b: Final = Foo.B
if x is final_a is final_b:
   reveal_type(x)   # E: Statement is unreachable
else:
   reveal_type(x)   # N: Revealed type is "__main__.Foo"
reveal_type(x)      # N: Revealed type is "__main__.Foo"

[builtins fixtures/primitives.pyi]

[case testEnumReachabilityWithChainingBigDisjoints]
# flags: --warn-unreachable
from enum import Enum
from typing import Final, Literal

class Foo(Enum):
    A = 1
    B = 2
    C = 3

    def __lt__(self, other: object) -> bool: return True

x0: Foo
x1: Foo
x2: Foo
x3: Foo
x4: Foo
x5: Foo

if x0 is x1 is Foo.A is x2 < x3 is Foo.B is x4 is x5:
    reveal_type(x0)  # N: Revealed type is "Literal[__main__.Foo.A]"
    reveal_type(x1)  # N: Revealed type is "Literal[__main__.Foo.A]"
    reveal_type(x2)  # N: Revealed type is "Literal[__main__.Foo.A]"

    reveal_type(x3)  # N: Revealed type is "Literal[__main__.Foo.B]"
    reveal_type(x4)  # N: Revealed type is "Literal[__main__.Foo.B]"
    reveal_type(x5)  # N: Revealed type is "Literal[__main__.Foo.B]"
else:
    # We unfortunately can't narrow away anything. For example,
    # what if x0 == Foo.A and x1 == Foo.B or vice versa?
    reveal_type(x0)  # N: Revealed type is "__main__.Foo"
    reveal_type(x1)  # N: Revealed type is "__main__.Foo"
    reveal_type(x2)  # N: Revealed type is "__main__.Foo"

    reveal_type(x3)  # N: Revealed type is "__main__.Foo"
    reveal_type(x4)  # N: Revealed type is "__main__.Foo"
    reveal_type(x5)  # N: Revealed type is "__main__.Foo"
[builtins fixtures/primitives.pyi]

[case testPrivateAttributeNotAsEnumMembers]
import enum

class Comparator(enum.Enum):
    LessThan = "<"
    LessThanOrEqualTo = "<="
    EqualTo = "=="
    NotEqualTo = "!="
    GreaterThanOrEqualTo = ">="
    GreaterThan = ">"

    __foo__ = {
        LessThan: 1,
        LessThanOrEqualTo: 2,
        EqualTo: 3,
        NotEqualTo: 4,
        GreaterThanOrEqualTo: 5,
        GreaterThan: 6,
    }

    def foo(self) -> int:
        return Comparator.__foo__[self.value]

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):
    def __init__(self, value: int) -> None:
        self.foo = "bar"
    A = 1
    B = 2

a = Foo.A
reveal_type(a.value)    # N: Revealed type is "Literal[1]? | Literal[2]?"
reveal_type(a._value_)  # N: Revealed type is "Literal[1]? | Literal[2]?"
[builtins fixtures/enum.pyi]

[case testNewSetsUnexpectedValueType]
from enum import Enum

class bytes:
    def __new__(cls): pass

class Foo(bytes, Enum):
    def __new__(cls, value: int) -> 'Foo':
        obj = bytes.__new__(cls)
        obj._value_ = "Number %d" % value
        return obj
    A = 1
    B = 2

a = Foo.A
reveal_type(a.value)    # N: Revealed type is "Any"
reveal_type(a._value_)  # N: Revealed type is "Any"
[builtins fixtures/tuple.pyi]
[typing fixtures/typing-medium.pyi]

[case testValueTypeWithNewInParentClass]
from enum import Enum

class bytes:
    def __new__(cls): pass

class Foo(bytes, Enum):
    def __new__(cls, value: int) -> 'Foo':
        obj = bytes.__new__(cls)
        obj._value_ = "Number %d" % value
        return obj

class Bar(Foo):
    A = 1
    B = 2

a = Bar.A
reveal_type(a.value)    # N: Revealed type is "Any"
reveal_type(a._value_)  # N: Revealed type is "Any"
[builtins fixtures/primitives.pyi]
[typing fixtures/typing-medium.pyi]

[case testValueTypeWithUserDataType]
from enum import Enum
from typing import Any

class Data:
    def __new__(cls, value: Any) -> Data: pass

class DataEnum(Data, Enum):
    A = Data(1)

reveal_type(DataEnum.A)          # N: Revealed type is "Literal[__main__.DataEnum.A]?"
reveal_type(DataEnum.A.value)    # N: Revealed type is "__main__.Data"
reveal_type(DataEnum.A._value_)  # N: Revealed type is "__main__.Data"
[builtins fixtures/tuple.pyi]

[case testEnumNarrowedToTwoLiterals]
# Regression test: two literals of an enum would be joined
# as the full type, regardless of the amount of elements
# the enum contains.
from enum import Enum
from typing import Literal, Union

class Foo(Enum):
    A = 1
    B = 2
    C = 3

def f(x: Foo):
    if x is Foo.A:
        return x
    if x is Foo.B:
        pass
    reveal_type(x) # N: Revealed type is "Literal[__main__.Foo.B] | Literal[__main__.Foo.C]"

[builtins fixtures/bool.pyi]

[case testEnumTypeCompatibleWithLiteralUnion]
from enum import Enum
from typing import Literal

class E(Enum):
    A = 1
    B = 2
    C = 3

e: E
a: Literal[E.A, E.B, E.C] = e
b: Literal[E.A, E.B] = e  # E: Incompatible types in assignment (expression has type "E", variable has type "Literal[E.A, E.B]")
c: Literal[E.A, E.C] = e  # E: Incompatible types in assignment (expression has type "E", variable has type "Literal[E.A, E.C]")
b = a  # E: Incompatible types in assignment (expression has type "Literal[E.A, E.B, E.C]", variable has type "Literal[E.A, E.B]")
[builtins fixtures/bool.pyi]

[case testIntEnumWithNewTypeValue]
from typing import NewType
from enum import IntEnum

N = NewType("N", int)

class E(IntEnum):
    A = N(0)

reveal_type(E.A.value) # N: Revealed type is "__main__.N"
[builtins fixtures/enum.pyi]


[case testEnumFinalValues]
from enum import Enum
class Medal(Enum):
    gold = 1
    silver = 2

# Another value:
Medal.gold = 0  # E: Cannot assign to final attribute "gold"
# Same value:
Medal.silver = 2  # E: Cannot assign to final attribute "silver"
[builtins fixtures/enum.pyi]


[case testEnumFinalValuesCannotRedefineValueProp]
from enum import Enum
class Types(Enum):
    key = 0
    value = 1
[builtins fixtures/enum.pyi]


[case testEnumReusedKeys]
# https://github.com/python/mypy/issues/11248
from enum import Enum
class Correct(Enum):
    x = 'y'
    y = 'x'
class Correct2(Enum):
    x = 'y'
    __z = 'y'
    __z = 'x'
class Foo(Enum):
    A = 1
    A = 'a'  # E: Attempted to reuse member name "A" in Enum definition "Foo" \
             # E: Incompatible types in assignment (expression has type "str", variable has type "int")
reveal_type(Foo.A.value)  # N: Revealed type is "Literal[1]?"

class Bar(Enum):
    A = 1
    B = A = 2  # E: Attempted to reuse member name "A" in Enum definition "Bar"
class Baz(Enum):
    A = 1
    B, A = (1, 2)  # E: Attempted to reuse member name "A" in Enum definition "Baz"
[builtins fixtures/tuple.pyi]

[case testEnumReusedKeysOverlapWithLocalVar]
from enum import Enum
x = 1
class Foo(Enum):
    x = 2
    def method(self) -> None:
        x = 3
x = 4
[builtins fixtures/bool.pyi]

[case testEnumImplicitlyFinalForSubclassing]
from enum import Enum, IntEnum, Flag, IntFlag

class NonEmptyEnum(Enum):
    x = 1
class NonEmptyIntEnum(IntEnum):
    x = 1
class NonEmptyFlag(Flag):
    x = 1
class NonEmptyIntFlag(IntFlag):
    x = 1

class ErrorEnumWithValue(NonEmptyEnum):  # E: Cannot extend enum with existing members: "NonEmptyEnum"
    x = 1  # E: Cannot override final attribute "x" (previously declared in base class "NonEmptyEnum")
class ErrorIntEnumWithValue(NonEmptyIntEnum):  # E: Cannot extend enum with existing members: "NonEmptyIntEnum"
    x = 1  # E: Cannot override final attribute "x" (previously declared in base class "NonEmptyIntEnum")
class ErrorFlagWithValue(NonEmptyFlag):  # E: Cannot extend enum with existing members: "NonEmptyFlag"
    x = 1  # E: Cannot override final attribute "x" (previously declared in base class "NonEmptyFlag")
class ErrorIntFlagWithValue(NonEmptyIntFlag):  # E: Cannot extend enum with existing members: "NonEmptyIntFlag"
    x = 1  # E: Cannot override final attribute "x" (previously declared in base class "NonEmptyIntFlag")

class ErrorEnumWithoutValue(NonEmptyEnum):  # E: Cannot extend enum with existing members: "NonEmptyEnum"
    pass
class ErrorIntEnumWithoutValue(NonEmptyIntEnum):  # E: Cannot extend enum with existing members: "NonEmptyIntEnum"
    pass
class ErrorFlagWithoutValue(NonEmptyFlag):  # E: Cannot extend enum with existing members: "NonEmptyFlag"
    pass
class ErrorIntFlagWithoutValue(NonEmptyIntFlag):  # E: Cannot extend enum with existing members: "NonEmptyIntFlag"
    pass
[builtins fixtures/bool.pyi]

[case testEnumImplicitlyFinalForSubclassingWithCallableMember]
# flags: --python-version 3.11
from enum import Enum, IntEnum, Flag, IntFlag, member

class NonEmptyEnum(Enum):
    @member
    def call(self) -> None: ...
class NonEmptyIntEnum(IntEnum):
    @member
    def call(self) -> None: ...
class NonEmptyFlag(Flag):
    @member
    def call(self) -> None: ...
class NonEmptyIntFlag(IntFlag):
    @member
    def call(self) -> None: ...

class ErrorEnumWithoutValue(NonEmptyEnum):  # E: Cannot extend enum with existing members: "NonEmptyEnum"
    pass
class ErrorIntEnumWithoutValue(NonEmptyIntEnum):  # E: Cannot extend enum with existing members: "NonEmptyIntEnum"
    pass
class ErrorFlagWithoutValue(NonEmptyFlag):  # E: Cannot extend enum with existing members: "NonEmptyFlag"
    pass
class ErrorIntFlagWithoutValue(NonEmptyIntFlag):  # E: Cannot extend enum with existing members: "NonEmptyIntFlag"
    pass
[builtins fixtures/bool.pyi]

[case testEnumCanExtendEnumsWithNonMembers]
# flags: --python-version 3.11
from enum import Enum, IntEnum, Flag, IntFlag, nonmember

class NonEmptyEnum(Enum):
    x = nonmember(1)
class NonEmptyIntEnum(IntEnum):
    x = nonmember(1)
class NonEmptyFlag(Flag):
    x = nonmember(1)
class NonEmptyIntFlag(IntFlag):
    x = nonmember(1)

class ErrorEnumWithoutValue(NonEmptyEnum):
    pass
class ErrorIntEnumWithoutValue(NonEmptyIntEnum):
    pass
class ErrorFlagWithoutValue(NonEmptyFlag):
    pass
class ErrorIntFlagWithoutValue(NonEmptyIntFlag):
    pass
[builtins fixtures/bool.pyi]

[case testLambdaIsNotEnumMember]
from enum import Enum

class My(Enum):
    x = lambda a: a

class Other(My): ...
[builtins fixtures/bool.pyi]

[case testSubclassingNonFinalEnums]
from enum import Enum, IntEnum, Flag, IntFlag, EnumMeta

def decorator(func):
    return func

class EmptyEnum(Enum):
    pass
class EmptyIntEnum(IntEnum):
    pass
class EmptyFlag(Flag):
    pass
class EmptyIntFlag(IntFlag):
    pass
class EmptyEnumMeta(EnumMeta):
    pass

class NonEmptyEnumSub(EmptyEnum):
    x = 1
class NonEmptyIntEnumSub(EmptyIntEnum):
    x = 1
class NonEmptyFlagSub(EmptyFlag):
    x = 1
class NonEmptyIntFlagSub(EmptyIntFlag):
    x = 1
class NonEmptyEnumMetaSub(EmptyEnumMeta):
    x = 1

class EmptyEnumSub(EmptyEnum):
    def method(self) -> None: pass
    @decorator
    def other(self) -> None: pass
class EmptyIntEnumSub(EmptyIntEnum):
    def method(self) -> None: pass
class EmptyFlagSub(EmptyFlag):
    def method(self) -> None: pass
class EmptyIntFlagSub(EmptyIntFlag):
    def method(self) -> None: pass
class EmptyEnumMetaSub(EmptyEnumMeta):
    def method(self) -> None: pass

class NestedEmptyEnumSub(EmptyEnumSub):
    x = 1
class NestedEmptyIntEnumSub(EmptyIntEnumSub):
    x = 1
class NestedEmptyFlagSub(EmptyFlagSub):
    x = 1
class NestedEmptyIntFlagSub(EmptyIntFlagSub):
    x = 1
class NestedEmptyEnumMetaSub(EmptyEnumMetaSub):
    x = 1
[builtins fixtures/bool.pyi]

[case testEnumExplicitlyAndImplicitlyFinal]
from typing import final
from enum import Enum, IntEnum, Flag, IntFlag, EnumMeta

@final
class EmptyEnum(Enum):
    pass
@final
class EmptyIntEnum(IntEnum):
    pass
@final
class EmptyFlag(Flag):
    pass
@final
class EmptyIntFlag(IntFlag):
    pass
@final
class EmptyEnumMeta(EnumMeta):
    pass

class EmptyEnumSub(EmptyEnum):  # E: Cannot inherit from final class "EmptyEnum"
    pass
class EmptyIntEnumSub(EmptyIntEnum):  # E: Cannot inherit from final class "EmptyIntEnum"
    pass
class EmptyFlagSub(EmptyFlag):  # E: Cannot inherit from final class "EmptyFlag"
    pass
class EmptyIntFlagSub(EmptyIntFlag):  # E: Cannot inherit from final class "EmptyIntFlag"
    pass
class EmptyEnumMetaSub(EmptyEnumMeta):  # E: Cannot inherit from final class "EmptyEnumMeta"
    pass

@final
class NonEmptyEnum(Enum):
    x = 1
@final
class NonEmptyIntEnum(IntEnum):
    x = 1
@final
class NonEmptyFlag(Flag):
    x = 1
@final
class NonEmptyIntFlag(IntFlag):
    x = 1
@final
class NonEmptyEnumMeta(EnumMeta):
    x = 1

class ErrorEnumWithoutValue(NonEmptyEnum):  # E: Cannot inherit from final class "NonEmptyEnum" \
                                            # E: Cannot extend enum with existing members: "NonEmptyEnum"
    pass
class ErrorIntEnumWithoutValue(NonEmptyIntEnum):  # E: Cannot inherit from final class "NonEmptyIntEnum" \
                                                  # E: Cannot extend enum with existing members: "NonEmptyIntEnum"
    pass
class ErrorFlagWithoutValue(NonEmptyFlag):  # E: Cannot inherit from final class "NonEmptyFlag" \
                                            # E: Cannot extend enum with existing members: "NonEmptyFlag"
    pass
class ErrorIntFlagWithoutValue(NonEmptyIntFlag):  # E: Cannot inherit from final class "NonEmptyIntFlag" \
                                                  # E: Cannot extend enum with existing members: "NonEmptyIntFlag"
    pass
class ErrorEnumMetaWithoutValue(NonEmptyEnumMeta):  # E: Cannot inherit from final class "NonEmptyEnumMeta"
    pass
[builtins fixtures/bool.pyi]

[case testEnumFinalSubtypingEnumMetaSpecialCase]
from enum import EnumMeta
# `EnumMeta` types are not `Enum`s
class SubMeta(EnumMeta):
    x = 1
class SubSubMeta(SubMeta):
    x = 2
[builtins fixtures/bool.pyi]

[case testEnumFinalSubtypingOverloadedSpecialCase]
from typing import overload
from enum import Enum, IntEnum, Flag, IntFlag, EnumMeta

class EmptyEnum(Enum):
    @overload
    def method(self, arg: int) -> int:
        pass
    @overload
    def method(self, arg: str) -> str:
        pass
    def method(self, arg):
        pass
class EmptyIntEnum(IntEnum):
    @overload
    def method(self, arg: int) -> int:
        pass
    @overload
    def method(self, arg: str) -> str:
        pass
    def method(self, arg):
        pass
class EmptyFlag(Flag):
    @overload
    def method(self, arg: int) -> int:
        pass
    @overload
    def method(self, arg: str) -> str:
        pass
    def method(self, arg):
        pass
class EmptyIntFlag(IntFlag):
    @overload
    def method(self, arg: int) -> int:
        pass
    @overload
    def method(self, arg: str) -> str:
        pass
    def method(self, arg):
        pass
class EmptyEnumMeta(EnumMeta):
    @overload
    def method(self, arg: int) -> int:
        pass
    @overload
    def method(self, arg: str) -> str:
        pass
    def method(self, arg):
        pass

class NonEmptyEnumSub(EmptyEnum):
    x = 1
class NonEmptyIntEnumSub(EmptyIntEnum):
    x = 1
class NonEmptyFlagSub(EmptyFlag):
    x = 1
class NonEmptyIntFlagSub(EmptyIntFlag):
    x = 1
class NonEmptyEnumMetaSub(EmptyEnumMeta):
    x = 1
[builtins fixtures/bool.pyi]

[case testEnumFinalSubtypingMethodAndValueSpecialCase]
from enum import Enum, IntEnum, Flag, IntFlag, EnumMeta

def decorator(func):
    return func

class NonEmptyEnum(Enum):
    x = 1
    def method(self) -> None: pass
    @decorator
    def other(self) -> None: pass
class NonEmptyIntEnum(IntEnum):
    x = 1
    def method(self) -> None: pass
class NonEmptyFlag(Flag):
    x = 1
    def method(self) -> None: pass
class NonEmptyIntFlag(IntFlag):
    x = 1
    def method(self) -> None: pass

class ErrorEnumWithoutValue(NonEmptyEnum):  # E: Cannot extend enum with existing members: "NonEmptyEnum"
    pass
class ErrorIntEnumWithoutValue(NonEmptyIntEnum):  # E: Cannot extend enum with existing members: "NonEmptyIntEnum"
    pass
class ErrorFlagWithoutValue(NonEmptyFlag):  # E: Cannot extend enum with existing members: "NonEmptyFlag"
    pass
class ErrorIntFlagWithoutValue(NonEmptyIntFlag):  # E: Cannot extend enum with existing members: "NonEmptyIntFlag"
    pass
[builtins fixtures/bool.pyi]

[case testFinalEnumWithClassDef]
from enum import Enum

class A(Enum):
    class Inner: pass
class B(A): pass  # E: Cannot extend enum with existing members: "A"

class A1(Enum):
    class __Inner: pass
class B1(A1): pass
[builtins fixtures/bool.pyi]

[case testEnumFinalSpecialProps]
# https://github.com/python/mypy/issues/11699
# https://github.com/python/mypy/issues/11820
from enum import Enum, IntEnum

class BaseWithSpecials:
    __slots__ = ()
    __doc__ = 'doc'
    __module__ = 'module'
    __annotations__ = {'a': int}
    __dict__ = {'a': 1}

class E(BaseWithSpecials, Enum):
    name = 'a'
    value = 'b'
    _name_ = 'a1'
    _value_ = 'b2'
    _order_ = 'X Y'
    __order__ = 'X Y'
    __slots__ = ()
    __doc__ = 'doc'
    __module__ = 'module'
    __annotations__ = {'a': int}
    __dict__ = {'a': 1}

class EI(IntEnum):
    name = 'a'
    value = 1
    _name_ = 'a1'
    _value_ = 2
    _order_ = 'X Y'
    __order__ = 'X Y'
    __slots__ = ()
    __doc__ = 'doc'
    __module__ = 'module'
    __annotations__ = {'a': int}
    __dict__ = {'a': 1}

E._order_ = 'a'  # E: Cannot assign to final attribute "_order_"
EI.value = 2     # E: Cannot assign to final attribute "value"
[builtins fixtures/dict.pyi]

[case testEnumNotFinalWithMethodsAndUninitializedValues]
# https://github.com/python/mypy/issues/11578
from enum import Enum
from typing import Final

class A(Enum):
    x: int
    def method(self) -> int: pass
class B(A):
    x = 1  # E: Cannot override writable attribute "x" with a final one \
           # E: Incompatible types in assignment (expression has type "B", base class "A" defined the type as "int")

class A1(Enum):
    x: int = 1  # E: Enum members must be left unannotated \
                # N: See https://typing.readthedocs.io/en/latest/spec/enums.html#defining-members
class B1(A1):  # E: Cannot extend enum with existing members: "A1"
    pass

class A2(Enum):
    x = 2
class B2(A2):  # E: Cannot extend enum with existing members: "A2"
    pass

# We leave this `Final` without a value,
# because we need to test annotation only mode:
class A3(Enum):
    x: Final[int]  # type: ignore
class B3(A3):
    x = 1  # E: Cannot override final attribute "x" (previously declared in base class "A3") \
           # E: Incompatible types in assignment (expression has type "B3", base class "A3" defined the type as "int")
[builtins fixtures/bool.pyi]

[case testEnumNotFinalWithMethodsAndUninitializedValuesStub]
import lib

[file lib.pyi]
from enum import Enum
class A(Enum):  # E: Detected enum "lib.A" in a type stub with zero members. There is a chance this is due to a recent change in the semantics of enum membership. If so, use `member = value` to mark an enum member, instead of `member: type` \
                # N: See https://typing.readthedocs.io/en/latest/spec/enums.html#defining-members
    x: int
class B(A):
    x = 1    # E: Cannot override writable attribute "x" with a final one \
             # E: Incompatible types in assignment (expression has type "B", base class "A" defined the type as "int")

class C(Enum):
    x = 1
class D(C):  # E: Cannot extend enum with existing members: "C" \
             # E: Detected enum "lib.D" in a type stub with zero members. There is a chance this is due to a recent change in the semantics of enum membership. If so, use `member = value` to mark an enum member, instead of `member: type` \
             # N: See https://typing.readthedocs.io/en/latest/spec/enums.html#defining-members
    x: int   # E: Incompatible types in assignment (expression has type "int", base class "C" defined the type as "C") \
             # E: Cannot assign to final name "x"
[builtins fixtures/bool.pyi]

[case testEnumNotFinalWithMethodsAndUninitializedValuesStubMember]
# flags: --python-version 3.11
# This was added in 3.11
import lib

[file lib.pyi]
from enum import Enum, member
class A(Enum):
    @member
    def x(self) -> None: ...
[builtins fixtures/bool.pyi]

[case testEnumLiteralValues]
from enum import Enum

class A(Enum):
    str = "foo"
    int = 1
    bool = False
    tuple = (1,)

reveal_type(A.str.value)  # N: Revealed type is "Literal['foo']?"
reveal_type(A.int.value)  # N: Revealed type is "Literal[1]?"
reveal_type(A.bool.value)  # N: Revealed type is "Literal[False]?"
reveal_type(A.tuple.value)  # N: Revealed type is "tuple[Literal[1]?]"
[builtins fixtures/tuple.pyi]

[case testFinalWithPrivateAssignment]
import enum
class Some(enum.Enum):
    __priv = 1

class Other(Some):  # Should pass
    pass
[builtins fixtures/tuple.pyi]

[case testFinalWithDunderAssignment]
import enum
class Some(enum.Enum):
    __some__ = 1

class Other(Some):  # Should pass
    pass
[builtins fixtures/tuple.pyi]

[case testFinalWithSunderAssignment]
import enum
class Some(enum.Enum):
    _some_ = 1

class Other(Some):  # Should pass
    pass
[builtins fixtures/tuple.pyi]

[case testFinalWithMethodAssignment]
import enum
from typing import overload
class Some(enum.Enum):
    def lor(self, other) -> bool:
        pass

    ror = lor

class Other(Some):  # Should pass
    pass


class WithOverload(enum.IntEnum):
    @overload
    def meth(self, arg: int) -> int: pass
    @overload
    def meth(self, arg: str) -> str: pass
    def meth(self, arg): pass

    alias = meth

class SubWithOverload(WithOverload):  # Should pass
    pass
[builtins fixtures/tuple.pyi]

[case testEnumBaseClassesOrder]
import enum

# Base types:

class First:
    def __new__(cls, val):
        pass

class Second:
    def __new__(cls, val):
        pass

class Third:
    def __new__(cls, val):
        pass

class Mixin:
    pass

class EnumWithCustomNew(enum.Enum):
    def __new__(cls, val):
        pass

class SecondEnumWithCustomNew(enum.Enum):
    def __new__(cls, val):
        pass

# Correct Enums:

class Correct0(enum.Enum):
    pass

class Correct1(Mixin, First, enum.Enum):
    pass

class Correct2(First, enum.Enum):
    pass

class Correct3(Mixin, enum.Enum):
    pass

class RegularClass(Mixin, First, Second):
    pass

class Correct5(enum.Enum):
    pass

# Correct inheritance:

class _InheritingDataAndMixin(Correct1):
    pass

class _CorrectWithData(First, Correct0):
    pass

class _CorrectWithDataAndMixin(Mixin, First, Correct0):
    pass

class _CorrectWithMixin(Mixin, Correct2):
    pass

class _CorrectMultipleEnumBases(Correct0, Correct5):
    pass

class _MultipleEnumBasesAndMixin(int, Correct0, enum.Flag):
    pass

class _MultipleEnumBasesWithCustomNew(int, EnumWithCustomNew, SecondEnumWithCustomNew):
    pass

# Wrong Enums:

class TwoDataTypesViaInheritance(Second, Correct2):  # E: Only a single data type mixin is allowed for Enum subtypes, found extra "__main__.Correct2"
    pass

class TwoDataTypesViaInheritanceAndMixin(Second, Correct2, Mixin):  # E: No non-enum mixin classes are allowed after "__main__.Correct2" \
                                                                    # E: Only a single data type mixin is allowed for Enum subtypes, found extra "__main__.Correct2"
    pass

class MixinAfterEnum1(enum.Enum, Mixin):  # E: No non-enum mixin classes are allowed after "enum.Enum"
    pass

class MixinAfterEnum2(First, enum.Enum, Mixin):  # E: No non-enum mixin classes are allowed after "enum.Enum"
    pass

class TwoDataTypes(First, Second, enum.Enum):  # E: Only a single data type mixin is allowed for Enum subtypes, found extra "__main__.Second"
    pass

class TwoDataTypesAndIntEnumMixin(First, Second, enum.IntEnum, Mixin):  # E: No non-enum mixin classes are allowed after "enum.IntEnum" \
                                                                        # E: Only a single data type mixin is allowed for Enum subtypes, found extra "__main__.Second"
    pass

class ThreeDataTypes(First, Second, Third, enum.Enum):  # E: Only a single data type mixin is allowed for Enum subtypes, found extra "__main__.Second" \
                                                        # E: Only a single data type mixin is allowed for Enum subtypes, found extra "__main__.Third"
    pass

class ThreeDataTypesAndMixin(First, Second, Third, enum.Enum, Mixin):  # E: No non-enum mixin classes are allowed after "enum.Enum" \
                                                                       # E: Only a single data type mixin is allowed for Enum subtypes, found extra "__main__.Second" \
                                                                       # E: Only a single data type mixin is allowed for Enum subtypes, found extra "__main__.Third"
    pass

class FromEnumAndOther1(Correct2, Second, enum.Enum):  # E: No non-enum mixin classes are allowed after "__main__.Correct2" \
                                                       # E: Only a single data type mixin is allowed for Enum subtypes, found extra "__main__.Second"
    pass

class FromEnumAndOther2(Correct2, Second):  # E: No non-enum mixin classes are allowed after "__main__.Correct2" \
                                            # E: Only a single data type mixin is allowed for Enum subtypes, found extra "__main__.Second"
    pass
[builtins fixtures/tuple.pyi]

[case testRegression12258]
from enum import Enum

class MyEnum(Enum): ...

class BytesEnum(bytes, MyEnum): ...  # Should be ok
[builtins fixtures/tuple.pyi]

[case testEnumWithNewHierarchy]
import enum

class A:
    def __new__(cls, val): ...
class B(A):
    def __new__(cls, val): ...
class C:
    def __new__(cls, val): ...

class E1(A, enum.Enum): ...
class E2(B, enum.Enum): ...

# Errors:

class W1(C, E1): ...  # E: Only a single data type mixin is allowed for Enum subtypes, found extra "__main__.E1"
class W2(C, E2): ...  # E: Only a single data type mixin is allowed for Enum subtypes, found extra "__main__.E2"
[builtins fixtures/tuple.pyi]

[case testEnumValueUnionSimplification]
from enum import IntEnum
from typing import Any

class C(IntEnum):
    X = 0
    Y = 1
    Z = 2

def f1(c: C) -> None:
    x = {'x': c.value}
    reveal_type(x)  # N: Revealed type is "builtins.dict[builtins.str, builtins.int]"

def f2(c: C, a: Any) -> None:
    x = {'x': c.value, 'y': a}
    reveal_type(x)  # N: Revealed type is "builtins.dict[builtins.str, Any]"
    y = {'y': a, 'x': c.value}
    reveal_type(y)  # N: Revealed type is "builtins.dict[builtins.str, Any]"
[builtins fixtures/dict.pyi]

[case testEnumIgnoreIsDeleted]
from enum import Enum

class C(Enum):
    _ignore_ = 'X'

C._ignore_ # E: "type[C]" has no attribute "_ignore_"
[builtins fixtures/enum.pyi]

[case testCanOverrideDunderAttributes]
import typing
from enum import Enum, Flag

class BaseEnum(Enum):
    __dunder__ = 1
    __labels__: typing.Dict[int, str]

class Override(BaseEnum):
    __dunder__ = 2
    __labels__ = {1: "1"}

Override.__dunder__ = 3
BaseEnum.__dunder__ = 3
Override.__labels__ = {2: "2"}

class FlagBase(Flag):
    __dunder__ = 1
    __labels__: typing.Dict[int, str]

class FlagOverride(FlagBase):
    __dunder__ = 2
    __labels = {1: "1"}

FlagOverride.__dunder__ = 3
FlagBase.__dunder__ = 3
FlagOverride.__labels__ = {2: "2"}
[builtins fixtures/dict.pyi]

[case testCanNotInitialize__members__]
import typing
from enum import Enum

class WritingMembers(Enum):
    __members__: typing.Dict[Enum, Enum] = {}  # E: Assigned "__members__" will be overridden by "Enum" internally

class OnlyAnnotatedMembers(Enum):
    __members__: typing.Dict[Enum, Enum]
[builtins fixtures/dict.pyi]

[case testCanOverrideDunderOnNonFirstBaseEnum]
import typing
from enum import Enum

class Some:
    __labels__: typing.Dict[int, str]

class A(Some, Enum):
    __labels__ = {1: "1"}
[builtins fixtures/dict.pyi]

[case testEnumWithPartialTypes]
from enum import Enum

class Mixed(Enum):
    a = []  # E: Need type annotation for "a" (hint: "a: list[<type>] = ...")
    b = None

    def check(self) -> None:
        reveal_type(Mixed.a.value)  # N: Revealed type is "builtins.list[Any]"
        reveal_type(Mixed.b.value)  # N: Revealed type is "None"

        # Inferring Any here instead of a union seems to be a deliberate
        # choice; see the testEnumValueInhomogeneous case above.
        reveal_type(self.value)  # N: Revealed type is "Any"

        for field in Mixed:
            reveal_type(field.value)  # N: Revealed type is "Any"
            if field.value is None:
                pass

class AllPartialList(Enum):
    a = []  # E: Need type annotation for "a" (hint: "a: list[<type>] = ...")
    b = []  # E: Need type annotation for "b" (hint: "b: list[<type>] = ...")

    def check(self) -> None:
        reveal_type(self.value)  # N: Revealed type is "builtins.list[Any]"
[builtins fixtures/tuple.pyi]

[case testEnumPrivateAttributeNotMember]
from enum import Enum

class MyEnum(Enum):
    A = 1
    B = 2
    __my_dict = {A: "ham", B: "spam"}

# TODO: change the next line to use MyEnum._MyEnum__my_dict when mypy implements name mangling
x: MyEnum = MyEnum.__my_dict  # E: Incompatible types in assignment (expression has type "dict[int, str]", variable has type "MyEnum")
[builtins fixtures/enum.pyi]

[case testEnumWithPrivateAttributeReachability]
# flags: --warn-unreachable
from enum import Enum

class MyEnum(Enum):
    A = 1
    B = 2
    __my_dict = {A: "ham", B: "spam"}

e: MyEnum
if e == MyEnum.A:
    reveal_type(e)  # N: Revealed type is "Literal[__main__.MyEnum.A]"
elif e == MyEnum.B:
    reveal_type(e)  # N: Revealed type is "Literal[__main__.MyEnum.B]"
else:
    reveal_type(e)  # E: Statement is unreachable
[builtins fixtures/dict.pyi]


[case testEnumNonMemberSupport]
# flags: --python-version 3.11
# This was added in 3.11
from enum import Enum, nonmember

class My(Enum):
    a = 1
    b = 2
    c = nonmember(3)

reveal_type(My.a)  # N: Revealed type is "Literal[__main__.My.a]?"
reveal_type(My.b)  # N: Revealed type is "Literal[__main__.My.b]?"
reveal_type(My.c)  # N: Revealed type is "builtins.int"

def accepts_my(my: My):
    reveal_type(my.value)  # N: Revealed type is "Literal[1]? | Literal[2]?"

class Other(Enum):
    a = 1
    @nonmember
    class Support:
        b = 2

reveal_type(Other.a)  # N: Revealed type is "Literal[__main__.Other.a]?"
reveal_type(Other.Support.b)  # N: Revealed type is "builtins.int"
[builtins fixtures/dict.pyi]


[case testEnumMemberSupport]
# flags: --python-version 3.11
# This was added in 3.11
from enum import Enum, member

class A(Enum):
    x = member(1)
    y = 2

reveal_type(A.x)  # N: Revealed type is "Literal[__main__.A.x]?"
reveal_type(A.x.value)  # N: Revealed type is "Literal[1]?"
reveal_type(A.y)  # N: Revealed type is "Literal[__main__.A.y]?"
reveal_type(A.y.value)  # N: Revealed type is "Literal[2]?"

def some_a(a: A):
    reveal_type(a.value)  # N: Revealed type is "Literal[1]? | Literal[2]?"
[builtins fixtures/dict.pyi]


[case testEnumMemberAndNonMemberSupport]
# flags: --python-version 3.11 --warn-unreachable
# This was added in 3.11
from enum import Enum, member, nonmember

class A(Enum):
    x = 1
    y = member(2)
    z = nonmember(3)

def some_a(a: A):
    if a is not A.x and a is not A.z:
        reveal_type(a)  # N: Revealed type is "Literal[__main__.A.y]"
    if a is not A.y and a is not A.z:
        reveal_type(a)  # N: Revealed type is "Literal[__main__.A.x]"
    if a is not A.x:
        reveal_type(a)  # N: Revealed type is "Literal[__main__.A.y]"
    if a is not A.y:
        reveal_type(a)  # N: Revealed type is "Literal[__main__.A.x]"
[builtins fixtures/dict.pyi]

[case testEnumAccessFromInstance]
# flags: --python-version 3.11 --warn-unreachable
# This was added in 3.11
from enum import Enum, member, nonmember

class A(Enum):
    x = 1
    y = member(2)
    z = nonmember(3)

reveal_type(A.x)  # N: Revealed type is "Literal[__main__.A.x]?"
reveal_type(A.y)  # N: Revealed type is "Literal[__main__.A.y]?"
reveal_type(A.z)  # N: Revealed type is "builtins.int"

reveal_type(A.x.x)  # N: Revealed type is "Literal[__main__.A.x]?"
reveal_type(A.x.x.x)  # N: Revealed type is "Literal[__main__.A.x]?"
reveal_type(A.x.y)  # N: Revealed type is "Literal[__main__.A.y]?"
reveal_type(A.x.y.y)  # N: Revealed type is "Literal[__main__.A.y]?"
reveal_type(A.x.z)  # N: Revealed type is "builtins.int"

reveal_type(A.y.x)  # N: Revealed type is "Literal[__main__.A.x]?"
reveal_type(A.y.y)  # N: Revealed type is "Literal[__main__.A.y]?"
reveal_type(A.y.z)  # N: Revealed type is "builtins.int"

A.z.x  # E: "int" has no attribute "x"

class B(Enum):
    x = 1
    value = 2

reveal_type(B.x)  # N: Revealed type is "Literal[__main__.B.x]?"
reveal_type(B.x.value)  # N: Revealed type is "Literal[2]?"
reveal_type(B.x.x.value)  # N: Revealed type is "Literal[2]?"
B.x.value.value  # E: "int" has no attribute "value"
B.x.value.value.value  # E: "int" has no attribute "value"
reveal_type(B.value)  # N: Revealed type is "Literal[__main__.B.value]?"
reveal_type(B.value.x)  # N: Revealed type is "Literal[__main__.B.x]?"
reveal_type(B.value.x.x)  # N: Revealed type is "Literal[__main__.B.x]?"
reveal_type(B.value.x.value)  # N: Revealed type is "Literal[2]?"
B.value.x.value.value  # E: "int" has no attribute "value"
B.value.value.value  # E: "int" has no attribute "value"
[builtins fixtures/dict.pyi]


[case testErrorOnAnnotatedMember]
from enum import Enum

class Medal(Enum):
    gold: int = 1  # E: Enum members must be left unannotated \
                   # N: See https://typing.readthedocs.io/en/latest/spec/enums.html#defining-members
    silver: str = 2  # E: Enum members must be left unannotated \
                     # N: See https://typing.readthedocs.io/en/latest/spec/enums.html#defining-members \
                     # E: Incompatible types in assignment (expression has type "int", variable has type "str")
    bronze = 3
[builtins fixtures/enum.pyi]

[case testEnumMemberWithPlaceholder]
from enum import Enum

class Pet(Enum):
    CAT = ...
    DOG: str = ...  # E: Enum members must be left unannotated \
                    # N: See https://typing.readthedocs.io/en/latest/spec/enums.html#defining-members \
                    # E: Incompatible types in assignment (expression has type "EllipsisType", variable has type "str")
[builtins fixtures/enum.pyi]

[case testEnumValueWithPlaceholderNodeType]
# https://github.com/python/mypy/issues/11971
from enum import Enum
from typing import Any, Callable, Dict
class Foo(Enum):
    Bar: Foo = Callable[[str], None]  # E: Enum members must be left unannotated \
                                      # N: See https://typing.readthedocs.io/en/latest/spec/enums.html#defining-members \
                                      # E: Incompatible types in assignment (expression has type "<typing special form>", variable has type "Foo")
    Baz: Any = Callable[[Dict[str, "Missing"]], None]  # E: Enum members must be left unannotated \
                                                       # N: See https://typing.readthedocs.io/en/latest/spec/enums.html#defining-members \
                                                       # E: Type application targets a non-generic function or class \
                                                       # E: Name "Missing" is not defined

reveal_type(Foo.Bar)  # N: Revealed type is "Literal[__main__.Foo.Bar]?"
reveal_type(Foo.Bar.value)  # N: Revealed type is "__main__.Foo"
reveal_type(Foo.Baz)  # N: Revealed type is "Literal[__main__.Foo.Baz]?"
reveal_type(Foo.Baz.value)  # N: Revealed type is "Any"
[builtins fixtures/tuple.pyi]
[typing fixtures/typing-full.pyi]


[case testEnumWithOnlyImplicitMembersUsingAnnotationOnly]
# flags: --warn-unreachable
import enum


class E(enum.IntEnum):
    A: int
    B: int


def do_check(value: E) -> None:
    reveal_type(value)  # N: Revealed type is "__main__.E"
    # this is a nonmember check, not an emum member check, and it should not narrow the value
    if value is E.A:
        return

    reveal_type(value)  # N: Revealed type is "__main__.E"
    "should be reachable"

[builtins fixtures/primitives.pyi]
[typing fixtures/typing-full.pyi]

[case testStrEnumClassCorrectIterable]
from enum import StrEnum
from typing import Type, TypeVar

class Choices(StrEnum):
    LOREM = "lorem"
    IPSUM = "ipsum"

var = list(Choices)
reveal_type(var)  # N: Revealed type is "builtins.list[__main__.Choices]"

e: type[StrEnum]
reveal_type(list(e))  # N: Revealed type is "builtins.list[enum.StrEnum]"

T = TypeVar("T", bound=StrEnum)
def list_vals(e: Type[T]) -> list[T]:
    reveal_type(list(e))  # N: Revealed type is "builtins.list[T`-1]"
    return list(e)

reveal_type(list_vals(Choices))  # N: Revealed type is "builtins.list[__main__.Choices]"
[builtins fixtures/enum.pyi]

[case testEnumAsClassMemberNoCrash]
# https://github.com/python/mypy/issues/18736
from enum import Enum

class Base:
    def __init__(self, namespace: tuple[str, ...]) -> None:
        # Not a bug: trigger defer
        names = [name for name in namespace if fail]  # E: Name "fail" is not defined
        self.o = Enum("o", names)  # E: Enum type as attribute is not supported \
                                   # E: Second argument of Enum() must be string, tuple, list or dict literal for mypy to determine Enum members
[builtins fixtures/tuple.pyi]

[case testSingleUnderscoreNameEnumMember]
# flags: --warn-unreachable

# https://github.com/python/mypy/issues/19271
from enum import Enum

class Things(Enum):
    _ = "under score"

def check(thing: Things) -> None:
    if thing is Things._:
        return None
    return None  # E: Statement is unreachable
[builtins fixtures/enum.pyi]

[case testSunderValueTypeEllipsis]
from foo.bar import (
    Basic, FromStub, InheritedInt, InheritedStr, InheritedFlag,
    InheritedIntFlag, Wrapper
)

reveal_type(Basic.FOO)  # N: Revealed type is "Literal[foo.bar.Basic.FOO]?"
reveal_type(Basic.FOO.value)  # N: Revealed type is "Literal[1]?"
reveal_type(Basic.FOO._value_)  # N: Revealed type is "builtins.int"

reveal_type(FromStub.FOO)  # N: Revealed type is "Literal[foo.bar.FromStub.FOO]?"
reveal_type(FromStub.FOO.value)  # N: Revealed type is "builtins.int"
reveal_type(FromStub.FOO._value_)  # N: Revealed type is "builtins.int"

reveal_type(Wrapper.Nested.FOO)  # N: Revealed type is "Literal[foo.bar.Wrapper.Nested.FOO]?"
reveal_type(Wrapper.Nested.FOO.value)  # N: Revealed type is "builtins.int"
reveal_type(Wrapper.Nested.FOO._value_)  # N: Revealed type is "builtins.int"

reveal_type(InheritedInt.FOO)  # N: Revealed type is "Literal[foo.bar.InheritedInt.FOO]?"
reveal_type(InheritedInt.FOO.value)  # N: Revealed type is "builtins.int"
reveal_type(InheritedInt.FOO._value_)  # N: Revealed type is "builtins.int"

reveal_type(InheritedStr.FOO)  # N: Revealed type is "Literal[foo.bar.InheritedStr.FOO]?"
reveal_type(InheritedStr.FOO.value)  # N: Revealed type is "builtins.str"
reveal_type(InheritedStr.FOO._value_)  # N: Revealed type is "builtins.str"

reveal_type(InheritedFlag.FOO)  # N: Revealed type is "Literal[foo.bar.InheritedFlag.FOO]?"
reveal_type(InheritedFlag.FOO.value)  # N: Revealed type is "builtins.int"
reveal_type(InheritedFlag.FOO._value_)  # N: Revealed type is "builtins.int"

reveal_type(InheritedIntFlag.FOO)  # N: Revealed type is "Literal[foo.bar.InheritedIntFlag.FOO]?"
reveal_type(InheritedIntFlag.FOO.value)  # N: Revealed type is "builtins.int"
reveal_type(InheritedIntFlag.FOO._value_)  # N: Revealed type is "builtins.int"

[file foo/__init__.pyi]
[file foo/bar/__init__.pyi]
from enum import Enum, IntEnum, StrEnum, Flag, IntFlag

class Basic(Enum):
    _value_: int
    FOO = 1

class FromStub(Enum):
    _value_: int
    FOO = ...

class Wrapper:
    class Nested(Enum):
        _value_: int
        FOO = ...

class InheritedInt(IntEnum):
    FOO = ...

class InheritedStr(StrEnum):
    FOO = ...

class InheritedFlag(Flag):
    FOO = ...

class InheritedIntFlag(IntFlag):
    FOO = ...
[builtins fixtures/enum.pyi]

[case testSunderValueTypeEllipsisNonStub]
from enum import Enum, StrEnum

class Basic(Enum):
    _value_: int
    FOO = 1

reveal_type(Basic.FOO)  # N: Revealed type is "Literal[__main__.Basic.FOO]?"
reveal_type(Basic.FOO.value)  # N: Revealed type is "Literal[1]?"
reveal_type(Basic.FOO._value_)  # N: Revealed type is "builtins.int"

# TODO: this and below should produce diagnostics, Ellipsis is not assignable to int
# Now we do not check members against _value_ at all.

class FromStub(Enum):
    _value_: int
    FOO = ...

reveal_type(FromStub.FOO)  # N: Revealed type is "Literal[__main__.FromStub.FOO]?"
reveal_type(FromStub.FOO.value)  # N: Revealed type is "types.EllipsisType"
reveal_type(FromStub.FOO._value_)  # N: Revealed type is "builtins.int"

class InheritedStr(StrEnum):
    FOO = ...

reveal_type(InheritedStr.FOO)  # N: Revealed type is "Literal[__main__.InheritedStr.FOO]?"
reveal_type(InheritedStr.FOO.value)  # N: Revealed type is "types.EllipsisType"
reveal_type(InheritedStr.FOO._value_)  # N: Revealed type is "types.EllipsisType"

class Wrapper:
    class Nested(StrEnum):
        FOO = ...

reveal_type(Wrapper.Nested.FOO)  # N: Revealed type is "Literal[__main__.Wrapper.Nested.FOO]?"
reveal_type(Wrapper.Nested.FOO.value)  # N: Revealed type is "types.EllipsisType"
reveal_type(Wrapper.Nested.FOO._value_)  # N: Revealed type is "types.EllipsisType"
[builtins fixtures/enum.pyi]

[case testStrEnumEqualityReachability]
# flags: --strict-equality --warn-unreachable

from __future__ import annotations
import enum

# https://github.com/python/mypy/issues/17162

class MyEnum(str, enum.Enum):
    A = 'a'

class MyEnum2(enum.StrEnum):
    A = 'a'

def f1():
    if MyEnum.A == 'a':
        1 + ''

    if MyEnum2.A == 'a':
        1 + ''
[builtins fixtures/primitives.pyi]

[case testStrEnumEqualityNarrowing]
# flags: --strict-equality --warn-unreachable

from __future__ import annotations
import enum
from typing import Literal

# https://github.com/python/mypy/issues/18029

class Foo(enum.StrEnum):
    A = 'a'

def f1(a: Foo | Literal['foo']) -> Foo:
    if a == 'foo':
        # Ideally this is narrowed to just Literal['foo'] (if we learn to narrow based on enum value)
        reveal_type(a)  # N: Revealed type is "__main__.Foo | Literal['foo']"
        return Foo.A

    reveal_type(a)  # N: Revealed type is "__main__.Foo"
    return a
[builtins fixtures/primitives.pyi]

[case testStrEnumEqualityAlias]
# flags: --strict-equality --warn-unreachable
# https://github.com/python/mypy/issues/16830
from __future__ import annotations
from enum import Enum, auto

# https://github.com/python/mypy/issues/16830

class TrafficLight(Enum):
    RED = auto()
    AMBER = auto()
    GREEN = auto()

    YELLOW = AMBER  # alias

# Behaviour here is not yet ideal, because we don't model enum aliases

def demo1(inst: TrafficLight) -> None:
    if inst is TrafficLight.AMBER:
        reveal_type(inst)  # N: Revealed type is "Literal[__main__.TrafficLight.AMBER]"
    else:
        reveal_type(inst)  # N: Revealed type is "Literal[__main__.TrafficLight.RED] | Literal[__main__.TrafficLight.GREEN] | Literal[__main__.TrafficLight.YELLOW]"

    if inst == TrafficLight.AMBER:
        reveal_type(inst)  # N: Revealed type is "Literal[__main__.TrafficLight.AMBER]"
    else:
        reveal_type(inst)  # N: Revealed type is "Literal[__main__.TrafficLight.RED] | Literal[__main__.TrafficLight.GREEN] | Literal[__main__.TrafficLight.YELLOW]"

def demo2() -> None:
    if TrafficLight.AMBER is TrafficLight.YELLOW:  # E: Non-overlapping identity check (left operand type: "Literal[TrafficLight.AMBER]", right operand type: "Literal[TrafficLight.YELLOW]")
        1 + ''  # E: Unsupported operand types for + ("int" and "str")
    else:
        1 + ''  # E: Unsupported operand types for + ("int" and "str")
[builtins fixtures/primitives.pyi]


[case testEnumEqualityNarrowing]
# flags: --strict-equality --warn-unreachable

from __future__ import annotations
from typing import cast
from enum import Enum, StrEnum

# https://github.com/python/mypy/issues/16830

class E(Enum):
    A = "a"
    B = "b"
    C = "c"

class Custom:
    def __eq__(self, other: object) -> bool: return True

class SE(StrEnum):
    A = "a"
    B = "b"
    C = "c"

def f1(x: int | str | E):
    if x == E.A:
        reveal_type(x)  # N: Revealed type is "Literal[__main__.E.A]"
    else:
        reveal_type(x)  # N: Revealed type is "builtins.int | builtins.str | Literal[__main__.E.B] | Literal[__main__.E.C]"

    if x in cast(list[E], []):
        reveal_type(x)  # N: Revealed type is "__main__.E"
    else:
        reveal_type(x)  # N: Revealed type is "builtins.int | builtins.str | __main__.E"

    if x == str():
        reveal_type(x)  # N: Revealed type is "builtins.str"
    else:
        reveal_type(x)  # N: Revealed type is "builtins.int | builtins.str | __main__.E"

def f2(x: int | Custom | E):
    if x == E.A:
        reveal_type(x)  # N: Revealed type is "__main__.Custom | Literal[__main__.E.A]"
    else:
        reveal_type(x)  # N: Revealed type is "builtins.int | __main__.Custom | Literal[__main__.E.B] | Literal[__main__.E.C]"

    if x in cast(list[E], []):
        reveal_type(x)  # N: Revealed type is "__main__.Custom | __main__.E"
    else:
        reveal_type(x)  # N: Revealed type is "builtins.int | __main__.Custom | __main__.E"

    if x == str():
        reveal_type(x)  # N: Revealed type is "__main__.Custom"
    else:
        reveal_type(x)  # N: Revealed type is "builtins.int | __main__.Custom | __main__.E"

def f3_simple(x: str | SE):
    if x == SE.A:
        # Note the union gets simplified
        reveal_type(x)  # N: Revealed type is "builtins.str"
    else:
        reveal_type(x)  # N: Revealed type is "builtins.str"

def f3(x: int | str | SE):
    if x == SE.A:
        reveal_type(x)  # N: Revealed type is "builtins.str"
    else:
        reveal_type(x)  # N: Revealed type is "builtins.int | builtins.str"

    if x in cast(list[SE], []):
        reveal_type(x)  # N: Revealed type is "builtins.str"
    else:
        reveal_type(x)  # N: Revealed type is "builtins.int | builtins.str | __main__.SE"

    if x == str():
        reveal_type(x)  # N: Revealed type is "builtins.str"
    else:
        reveal_type(x)  # N: Revealed type is "builtins.int | builtins.str | __main__.SE"

def f4(x: int | Custom | SE):
    if x == SE.A:
        reveal_type(x)  # N: Revealed type is "__main__.Custom | Literal[__main__.SE.A]"
    else:
        reveal_type(x)  # N: Revealed type is "builtins.int | __main__.Custom | Literal[__main__.SE.B] | Literal[__main__.SE.C]"

    if x in cast(list[SE], []):
        reveal_type(x)  # N: Revealed type is "__main__.Custom | __main__.SE"
    else:
        reveal_type(x)  # N: Revealed type is "builtins.int | __main__.Custom | __main__.SE"

    if x == str():
        reveal_type(x)  # N: Revealed type is "__main__.Custom | __main__.SE"
    else:
        reveal_type(x)  # N: Revealed type is "builtins.int | __main__.Custom | __main__.SE"

def f5(x: str | Custom | SE):
    if x == SE.A:
        reveal_type(x)  # N: Revealed type is "builtins.str | __main__.Custom"
    else:
        reveal_type(x)  # N: Revealed type is "builtins.str | __main__.Custom"

    if x in cast(list[SE], []):
        reveal_type(x)  # N: Revealed type is "builtins.str | __main__.Custom"
    else:
        reveal_type(x)  # N: Revealed type is "builtins.str | __main__.Custom | __main__.SE"

    if x == str():
        reveal_type(x)  # N: Revealed type is "builtins.str | __main__.Custom"
    else:
        reveal_type(x)  # N: Revealed type is "builtins.str | __main__.Custom | __main__.SE"

[builtins fixtures/primitives.pyi]


[case testNarrowingWithIntEnumAndStrEnumUnionAmbiguous]
# flags: --strict-equality --warn-unreachable
from __future__ import annotations
from enum import IntEnum, StrEnum

class IE(IntEnum):
    X = 1
    Y = 2

class SE(StrEnum):
    A = "a"
    B = "b"

def f(x: IE | SE) -> None:
    if x == IE.X:
        reveal_type(x)  # N: Revealed type is "Literal[__main__.IE.X]"
    else:
        reveal_type(x)  # N: Revealed type is "Literal[__main__.IE.Y] | __main__.SE"
[builtins fixtures/primitives.pyi]


[case testNarrowingWithStrEnumUnionNoneAmbiguous]
# flags: --strict-equality --warn-unreachable
from __future__ import annotations
from enum import StrEnum

class SE(StrEnum):
    A = "a"
    B = "b"

def f(x: SE | None) -> None:
    if x == "a":
        reveal_type(x)  # N: Revealed type is "__main__.SE"
    else:
        reveal_type(x)  # N: Revealed type is "__main__.SE | None"
[builtins fixtures/primitives.pyi]


[case testCallableEnumNarrowing]
# See: https://github.com/python/mypy/issues/17222

import enum

class Foo(enum.Enum):
     FOO1 = enum.auto()
     FOO2 = enum.auto()

     def __call__(self) -> str:
         return self.name

foo = Foo.FOO1

match foo:
     case Foo.FOO1:
        foo()
        reveal_type(foo) # N: Revealed type is "Literal[__main__.Foo.FOO1]"
     case _:
        foo()
        reveal_type(foo) # N: Revealed type is "Literal[__main__.Foo.FOO2]"
[builtins fixtures/primitives.pyi]