test-data/unit/check-python38.test

[case testDecoratedClassLine]
def d(c): ...
@d

class C: ...
class C: ...  # E: Name 'C' already defined on line 4

[case testDecoratedFunctionLine]
# flags: --disallow-untyped-defs
def d(f): ...  # type: ignore
@d

def f(): ...  # E: Function is missing a return type annotation \
              # N: Use "-> None" if function does not return a value

[case testIgnoreDecoratedFunction1]
# flags: --disallow-untyped-defs --warn-unused-ignores
def d(f): ...  # type: ignore
@d
# type: ignore
def f(): ...  # type: ignore  # E: unused 'type: ignore' comment

[case testIgnoreDecoratedFunction2]
# flags: --disallow-untyped-defs
def d(f): ...  # type: ignore
@d

def f(): ...  # type: ignore

[case testIgnoreScopeIssue1032]
def f(a: int): ...
f(
    1,
    2,
)  # type: ignore

[case testIgnoreScopeNested1]
def g(x: str) -> str: ...
def f(a: int) -> int: ...
f(
    f(
        g(
            "IGNORE"
        )  # type: ignore
    )
)

[case testIgnoreScopeNested2]
[
    "IGNORE"  # type: ignore
    &
    "IGNORE",
]
[builtins fixtures/list.pyi]

[case testIgnoreScopeNested3]
{
    "IGNORE"
    |  # type: ignore
    "IGNORE",
}
[builtins fixtures/set.pyi]

[case testIgnoreScopeNested4]
{
    None: "IGNORE"
    ^
    "IGNORE",  # type: ignore
}
[builtins fixtures/dict.pyi]

[case testIgnoreScopeNestedNonOverlapping]
def f(x: int): ...
def g(x: int): ...
(
    f("ERROR"),  # E: Argument 1 to "f" has incompatible type "str"; expected "int"
    g("IGNORE"),  # type: ignore
    f("ERROR"),  # E: Argument 1 to "f" has incompatible type "str"; expected "int"
)
[builtins fixtures/tuple.pyi]

[case testIgnoreScopeNestedOverlapping]
def f(x: int): ...
def g(x: int): ...
(
    f("ERROR"), g(  # E: Argument 1 to "f" has incompatible type "str"; expected "int"
        "IGNORE"  # type: ignore
    ), f("ERROR"),  # E: Argument 1 to "f" has incompatible type "str"; expected "int"
)
[builtins fixtures/tuple.pyi]

[case testIgnoreScopeUnused1]
# flags: --warn-unused-ignores
(  # type: ignore  # E: unused 'type: ignore' comment
    "IGNORE"  # type: ignore  # E: unused 'type: ignore' comment
    +  # type: ignore  # E: unused 'type: ignore' comment
    0  # type: ignore
)  # type: ignore  # E: unused 'type: ignore' comment
[builtins fixtures/primitives.pyi]

[case testIgnoreScopeUnused2]
# flags: --warn-unused-ignores
(  # type: ignore  # E: unused 'type: ignore' comment
    "IGNORE"
    -  # type: ignore
    0  # type: ignore  # E: unused 'type: ignore' comment
)  # type: ignore  # E: unused 'type: ignore' comment

[case testIgnoreScopeUnused3]
# flags: --warn-unused-ignores
(  # type: ignore  # E: unused 'type: ignore' comment
    "IGNORE"
    /
    0  # type: ignore
)  # type: ignore  # E: unused 'type: ignore' comment

[case testPEP570ArgTypesMissing]
# flags: --disallow-untyped-defs
def f(arg, /) -> None: ...  # E: Function is missing a type annotation for one or more arguments

[case testPEP570ArgTypesBadDefault]
def f(arg: int = "ERROR", /) -> None: ...  # E: Incompatible default for argument "arg" (default has type "str", argument has type "int")

[case testPEP570ArgTypesDefault]
def f(arg: int = 0, /) -> None:
    reveal_type(arg)  # N: Revealed type is 'builtins.int'

[case testPEP570ArgTypesRequired]
def f(arg: int, /) -> None:
    reveal_type(arg)  # N: Revealed type is 'builtins.int'

[case testPEP570Required]
def f(arg: int, /) -> None: ...  # N: "f" defined here
f(1)
f("ERROR")  # E: Argument 1 to "f" has incompatible type "str"; expected "int"
f(arg=1)  # E: Unexpected keyword argument "arg" for "f"
f(arg="ERROR")  # E: Unexpected keyword argument "arg" for "f"

[case testPEP570Default]
def f(arg: int = 0, /) -> None: ...  # N: "f" defined here
f()
f(1)
f("ERROR")  # E: Argument 1 to "f" has incompatible type "str"; expected "int"
f(arg=1)  # E: Unexpected keyword argument "arg" for "f"
f(arg="ERROR")  # E: Unexpected keyword argument "arg" for "f"

[case testPEP570Calls]
from typing import Any, Dict
def f(p, /, p_or_kw, *, kw) -> None: ...  # N: "f" defined here
d = None # type: Dict[Any, Any]
f(0, 0, 0)  # E: Too many positional arguments for "f"
f(0, 0, kw=0)
f(0, p_or_kw=0, kw=0)
f(p=0, p_or_kw=0, kw=0)  # E: Unexpected keyword argument "p" for "f"
f(0, **d)
f(**d)  # E: Missing positional argument "p_or_kw" in call to "f"
[builtins fixtures/dict.pyi]

[case testPEP570Signatures1]
def f(p1: bytes, p2: float, /, p_or_kw: int, *, kw: str) -> None:
    reveal_type(p1)  # N: Revealed type is 'builtins.bytes'
    reveal_type(p2)  # N: Revealed type is 'builtins.float'
    reveal_type(p_or_kw)  # N: Revealed type is 'builtins.int'
    reveal_type(kw)  # N: Revealed type is 'builtins.str'

[case testPEP570Signatures2]
def f(p1: bytes, p2: float = 0.0, /, p_or_kw: int = 0, *, kw: str) -> None:
    reveal_type(p1)  # N: Revealed type is 'builtins.bytes'
    reveal_type(p2)  # N: Revealed type is 'builtins.float'
    reveal_type(p_or_kw)  # N: Revealed type is 'builtins.int'
    reveal_type(kw)  # N: Revealed type is 'builtins.str'

[case testPEP570Signatures3]
def f(p1: bytes, p2: float = 0.0, /, *, kw: int) -> None:
    reveal_type(p1)  # N: Revealed type is 'builtins.bytes'
    reveal_type(p2)  # N: Revealed type is 'builtins.float'
    reveal_type(kw)  # N: Revealed type is 'builtins.int'

[case testPEP570Signatures4]
def f(p1: bytes, p2: int = 0, /) -> None:
    reveal_type(p1)  # N: Revealed type is 'builtins.bytes'
    reveal_type(p2)  # N: Revealed type is 'builtins.int'

[case testPEP570Signatures5]
def f(p1: bytes, p2: float, /, p_or_kw: int) -> None:
    reveal_type(p1)  # N: Revealed type is 'builtins.bytes'
    reveal_type(p2)  # N: Revealed type is 'builtins.float'
    reveal_type(p_or_kw)  # N: Revealed type is 'builtins.int'

[case testPEP570Signatures6]
def f(p1: bytes, p2: float, /) -> None:
    reveal_type(p1)  # N: Revealed type is 'builtins.bytes'
    reveal_type(p2)  # N: Revealed type is 'builtins.float'

[case testWalrus]
# flags: --strict-optional
from typing import NamedTuple, Optional, List
from typing_extensions import Final

if a := 2:
    reveal_type(a)  # N: Revealed type is 'builtins.int'

while b := "x":
    reveal_type(b)  # N: Revealed type is 'builtins.str'

l = [y2 := 1, y2 + 2, y2 + 3]
reveal_type(y2)  # N: Revealed type is 'builtins.int'
reveal_type(l)  # N: Revealed type is 'builtins.list[builtins.int*]'
 
filtered_data = [y3 for x in l if (y3 := a) is not None]
reveal_type(filtered_data)  # N: Revealed type is 'builtins.list[builtins.int*]'
reveal_type(y3)  # N: Revealed type is 'builtins.int'

d = {'a': (a2 := 1), 'b': a2 + 1, 'c': a2 + 2}
reveal_type(d)  # N: Revealed type is 'builtins.dict[builtins.str*, builtins.int*]'
reveal_type(a2)  # N: Revealed type is 'builtins.int'

d2 = {(prefix := 'key_') + 'a': (start_val := 1), prefix + 'b': start_val + 1, prefix + 'c': start_val + 2}
reveal_type(d2)  # N: Revealed type is 'builtins.dict[builtins.str*, builtins.int*]'
reveal_type(prefix)  # N: Revealed type is 'builtins.str'
reveal_type(start_val)  # N: Revealed type is 'builtins.int'

filtered_dict = {k: new_v for k, v in [('a', 1), ('b', 2), ('c', 3)] if (new_v := v + 1) == 2}
reveal_type(filtered_dict)  # N: Revealed type is 'builtins.dict[builtins.str*, builtins.int*]'
reveal_type(new_v)  # N: Revealed type is 'builtins.int'

def f(x: int = (c := 4)) -> int:
    if a := 2:
        reveal_type(a)  # N: Revealed type is 'builtins.int'

    while b := "x":
        reveal_type(b)  # N: Revealed type is 'builtins.str'

    x = (y := 1) + (z := 2)
    reveal_type(x)  # N: Revealed type is 'builtins.int'
    reveal_type(y)  # N: Revealed type is 'builtins.int'
    reveal_type(z)  # N: Revealed type is 'builtins.int'

    l = [y2 := 1, y2 + 2, y2 + 3]
    reveal_type(y2)  # N: Revealed type is 'builtins.int'
    reveal_type(l)  # N: Revealed type is 'builtins.list[builtins.int*]'

    filtered_data = [y3 for x in l if (y3 := a) is not None]
    reveal_type(filtered_data)  # N: Revealed type is 'builtins.list[builtins.int*]'
    reveal_type(y3)  # N: Revealed type is 'builtins.int'

    d = {'a': (a2 := 1), 'b': a2 + 1, 'c': a2 + 2}
    reveal_type(d)  # N: Revealed type is 'builtins.dict[builtins.str*, builtins.int*]'
    reveal_type(a2)  # N: Revealed type is 'builtins.int'

    d2 = {(prefix := 'key_') + 'a': (start_val := 1), prefix + 'b': start_val + 1, prefix + 'c': start_val + 2}
    reveal_type(d2)  # N: Revealed type is 'builtins.dict[builtins.str*, builtins.int*]'
    reveal_type(prefix)  # N: Revealed type is 'builtins.str'
    reveal_type(start_val)  # N: Revealed type is 'builtins.int'

    filtered_dict = {k: new_v for k, v in [('a', 1), ('b', 2), ('c', 3)] if (new_v := v + 1) == 2}
    reveal_type(filtered_dict)  # N: Revealed type is 'builtins.dict[builtins.str*, builtins.int*]'
    reveal_type(new_v)  # N: Revealed type is 'builtins.int'

    # https://www.python.org/dev/peps/pep-0572/#exceptional-cases
    (y4 := 3)
    reveal_type(y4)  # N: Revealed type is 'builtins.int'

    y5 = (y6 := 3)
    reveal_type(y5)  # N: Revealed type is 'builtins.int'
    reveal_type(y6)  # N: Revealed type is 'builtins.int'

    f(x=(y7 := 3))
    reveal_type(y7)  # N: Revealed type is 'builtins.int'

    reveal_type((lambda: (y8 := 3) and y8)())  # N: Revealed type is 'Literal[3]?'
    y8  # E: Name 'y8' is not defined

    y7 = 1.0  # E: Incompatible types in assignment (expression has type "float", variable has type "int")
    if y7 := "x":  # E: Incompatible types in assignment (expression has type "str", variable has type "int")
        pass

    # Just make sure we don't crash on this sort of thing.
    if NT := NamedTuple("NT", [("x", int)]):  # E: "int" not callable
        z2: NT  # E: Variable "NT" is not valid as a type \
                # N: See https://mypy.readthedocs.io/en/stable/common_issues.html#variables-vs-type-aliases

    if Alias := int:
        z3: Alias  # E: Variable "Alias" is not valid as a type \
                   # N: See https://mypy.readthedocs.io/en/stable/common_issues.html#variables-vs-type-aliases

    if (reveal_type(y9 := 3) and   # N: Revealed type is 'Literal[3]?'
            reveal_type(y9)):       # N: Revealed type is 'builtins.int'
        reveal_type(y9)            # N: Revealed type is 'builtins.int'

    return (y10 := 3) + y10

reveal_type(c)  # N: Revealed type is 'builtins.int'

def check_final() -> None:
    x: Final = 3

    if x := 4:  # E: Cannot assign to final name "x"
        pass

def check_binder(x: Optional[int], y: Optional[int], z: Optional[int], a: Optional[int],
                 b: Optional[int]) -> None:
    reveal_type(x)  # N: Revealed type is 'Union[builtins.int, None]'

    (x := 1)
    reveal_type(x)  # N: Revealed type is 'builtins.int'

    if x or (y := 1):
        reveal_type(y)  # N: Revealed type is 'Union[builtins.int, None]'

    if x and (y := 1):
        reveal_type(y)  # N: Revealed type is 'builtins.int'

    if (a := 1) and x:
        reveal_type(a)  # N: Revealed type is 'builtins.int'

    if (b := 1) or x:
        reveal_type(b)  # N: Revealed type is 'builtins.int'

    if z := 1:
        reveal_type(z)  # N: Revealed type is 'builtins.int'

def check_partial() -> None:
    x = None
    if bool() and (x := 2):
        pass

    reveal_type(x)  # N: Revealed type is 'Union[builtins.int, None]'

def check_narrow(x: Optional[int], s: List[int]) -> None:
    if (y := x):
        reveal_type(y)  # N: Revealed type is 'builtins.int'

    if (y := x) is not None:
        reveal_type(y)  # N: Revealed type is 'builtins.int'

    if (y := x) == 10:
        reveal_type(y)  # N: Revealed type is 'builtins.int'

    if (y := x) in s:
        reveal_type(y)  # N: Revealed type is 'builtins.int'

    if isinstance((y := x), int):
        reveal_type(y)  # N: Revealed type is 'builtins.int'

class AssignmentExpressionsClass:
    x = (y := 1) + (z := 2)
    reveal_type(z)  # N: Revealed type is 'builtins.int'

    l = [x2 := 1, 2, 3]
    reveal_type(x2)  # N: Revealed type is 'builtins.int'

    def __init__(self) -> None:
        reveal_type(self.z)  # N: Revealed type is 'builtins.int'

        l = [z2 := 1, z2 + 2, z2 + 3]
        reveal_type(z2)  # N: Revealed type is 'builtins.int'
        reveal_type(l)  # N: Revealed type is 'builtins.list[builtins.int*]'

        filtered_data = [z3 for x in l if (z3 := 1) is not None]
        reveal_type(filtered_data)  # N: Revealed type is 'builtins.list[builtins.int*]'
        reveal_type(z3)  # N: Revealed type is 'builtins.int'

# Assignment expressions from inside the class should not escape the class scope.
reveal_type(x2)  # E: Name 'x2' is not defined  # N: Revealed type is 'Any'
reveal_type(z2)  # E: Name 'z2' is not defined  # N: Revealed type is 'Any'

[builtins fixtures/isinstancelist.pyi]

[case testWalrusPartialTypes]
from typing import List

def check_partial_list() -> None:
    if (x := []):  # E: Need type annotation for "x" (hint: "x: List[<type>] = ...")
        pass

    y: List[str]
    if (y := []):
        pass

    if (z := []):
        z.append(3)
    reveal_type(z)  # N: Revealed type is 'builtins.list[builtins.int]'
[builtins fixtures/list.pyi]

[case testWalrusExpr]
def func() -> None:
    foo = Foo()
    if x := foo.x:
        pass

class Foo:
    def __init__(self) -> None:
        self.x = 123

[case testWalrusTypeGuard]
from typing_extensions import TypeGuard
def is_float(a: object) -> TypeGuard[float]: pass
def main(a: object) -> None:
    if is_float(x := a):
        reveal_type(x)  # N: Revealed type is 'builtins.float'
        reveal_type(a)  # N: Revealed type is 'builtins.object'
[builtins fixtures/tuple.pyi]