test-data/unit/check-varargs.test

-- Test cases for the type checker related to varargs.


-- Varargs within body
-- -------------------


[case testVarArgsWithinFunction]
from typing import Tuple
def f( *b: 'B') -> None:
    ab: Tuple[B, ...]
    ac: Tuple[C, ...]
    if int():
        b = ac # E: Incompatible types in assignment (expression has type "tuple[C, ...]", variable has type "tuple[B, ...]")
        ac = b # E: Incompatible types in assignment (expression has type "tuple[B, ...]", variable has type "tuple[C, ...]")
        b = ab
        ab = b

class B: pass
class C: pass
[builtins fixtures/tuple.pyi]
[out]


[case testVarArgsAreTuple]
from typing import Tuple, Sequence
def want_tuple(types: Tuple[type, ...]): pass
def want_sequence(types: Sequence[type]): pass
def test(*t: type) -> None:
    want_tuple(t)
    want_sequence(t)
[builtins fixtures/tuple.pyi]
[out]


-- Calling varargs function
-- ------------------------


[case testCallingVarArgsFunction]
def f( *a: 'A') -> None: pass

def g() -> None: pass

class A: pass
class B(A): pass
class C: pass

a: A
b: B
c: C

f(c)       # E: Argument 1 to "f" has incompatible type "C"; expected "A"
f(a, b, c) # E: Argument 3 to "f" has incompatible type "C"; expected "A"
f(g())     # E: "g" does not return a value (it only ever returns None) \
           # E: Argument 1 to "f" has incompatible type "None"; expected "A"
f(a, g())  # E: "g" does not return a value (it only ever returns None) \
           # E: Argument 2 to "f" has incompatible type "None"; expected "A"
f()
f(a)
f(b)
f(a, b, a, b)
[builtins fixtures/list.pyi]

[case testCallingVarArgsFunctionWithAlsoNormalArgs]
def f(a: 'C', *b: 'A') -> None: pass

class A: pass
class B(A): pass
class C: pass

a: A
b: B
c: C

f(a)       # E: Argument 1 to "f" has incompatible type "A"; expected "C"
f(c, c)    # E: Argument 2 to "f" has incompatible type "C"; expected "A"
f(c, a, b, c)  # E: Argument 4 to "f" has incompatible type "C"; expected "A"
f(c)
f(c, a)
f(c, b, b, a, b)
[builtins fixtures/list.pyi]

[case testCallingVarArgsFunctionWithDefaultArgs]
# flags: --implicit-optional --no-strict-optional
def f(a: 'C' = None, *b: 'A') -> None:
    pass

class A: pass
class B(A): pass
class C: pass

a: A
b: B
c: C

f(a)           # E: Argument 1 to "f" has incompatible type "A"; expected "C | None"
f(c, c)        # E: Argument 2 to "f" has incompatible type "C"; expected "A"
f(c, a, b, c)  # E: Argument 4 to "f" has incompatible type "C"; expected "A"
f()
f(c)
f(c, a)
f(c, b, b, a, b)
[builtins fixtures/list.pyi]

[case testCallVarargsFunctionWithIterable]
from typing import Iterable
it1: Iterable[int]
it2: Iterable[str]
def f(*x: int) -> None: pass
f(*it1)
f(*it2) # E: Argument 1 to "f" has incompatible type "*Iterable[str]"; expected "int"
[builtins fixtures/for.pyi]

[case testCallVarargsFunctionWithTwoTupleStarArgs]
from typing import TypeVar, Tuple

T1 = TypeVar('T1')
T2 = TypeVar('T2')
T3 = TypeVar('T3')
T4 = TypeVar('T4')

def f(a: T1, b: T2, c: T3, d: T4) -> Tuple[T1, T2, T3, T4]: ...
x: Tuple[int, str]
y: Tuple[float, bool]
reveal_type(f(*x, *y)) # N: Revealed type is "tuple[builtins.int, builtins.str, builtins.float, builtins.bool]"
[builtins fixtures/list.pyi]

[case testCallVarargsFunctionWithIterableAndPositional]

from typing import Iterable
it1: Iterable[int]
def f(*x: int) -> None: pass
f(*it1, 1, 2)
f(*it1, 1, *it1, 2)
f(*it1, '') # E: Argument 2 to "f" has incompatible type "str"; expected "int"
[builtins fixtures/for.pyi]

[case testCallVarargsFunctionWithTupleAndPositional]

def f(*x: int) -> None: pass
it1 = (1, 2)
it2 = ('',)
f(*it1, 1, 2)
f(*it1, 1, *it1, 2)
f(*it1, 1, *it2, 2)  # E: Argument 3 to "f" has incompatible type "*tuple[str]"; expected "int"
f(*it1, '') # E: Argument 2 to "f" has incompatible type "str"; expected "int"
[builtins fixtures/for.pyi]

[case testCallVarArgsWithMatchingNamedArgument]
def foo(*args: int) -> None: ...
foo(args=1)  # E: Unexpected keyword argument "args" for "foo"

def bar(*args: int, **kwargs: str) -> None: ...
bar(args=1)  # E: Argument "args" to "bar" has incompatible type "int"; expected "str"
[builtins fixtures/for.pyi]


-- Calling varargs function + type inference
-- -----------------------------------------


[case testTypeInferenceWithCalleeVarArgs]
from typing import TypeVar
T = TypeVar('T')

def f( *a: T) -> T:
    pass

class A: pass
class B(A): pass
class C: pass

a: A
b: B
c: C
o: object

if int():
    a = f(o) # E: Incompatible types in assignment (expression has type "object", variable has type "A")
if int():
    b = f(b, a) # E: Incompatible types in assignment (expression has type "A", variable has type "B")
if int():
    b = f(a, b) # E: Incompatible types in assignment (expression has type "A", variable has type "B")

if int():
    o = f()
if int():
    a = f(a)
if int():
    a = f(b)
if int():
    a = f(a, b, a)
if int():
    o = f(a, b, o)
if int():
    c = f(c)
[builtins fixtures/list.pyi]

[case testTypeInferenceWithCalleeVarArgsAndDefaultArgs]
# flags: --no-strict-optional
from typing import TypeVar
T = TypeVar('T')
a = None # type: A
o = None # type: object

def f(a: T, b: T = None, *c: T) -> T:
    pass

class A: pass

if int():
    a = f(o) # E: Incompatible types in assignment (expression has type "object", variable has type "A")
if int():
    a = f(a, o) # E: Incompatible types in assignment (expression has type "object", variable has type "A")
if int():
    a = f(a, a, o) # E: Incompatible types in assignment (expression has type "object", variable has type "A")
if int():
    a = f(a, a, a, o) # E: Incompatible types in assignment (expression has type "object", variable has type "A")

if int():
    a = f(a)
if int():
    a = f(a, a)
if int():
    a = f(a, a, a)
[builtins fixtures/list.pyi]


-- Calling normal function with varargs
-- ------------------------------------


[case testCallingWithListVarArgs]
from typing import List, Any, cast

def f(a: 'A', b: 'B') -> None:
    pass

class A: pass
class B: pass

aa: List[A]
ab: List[B]
a: A
b: B

f(*aa)  # E: Argument 1 to "f" has incompatible type "*list[A]"; expected "B"
f(a, *ab) # Ok
f(a, b)
(cast(Any, f))(*aa)     # IDEA: Move to check-dynamic?
(cast(Any, f))(a, *ab)  # IDEA: Move to check-dynamic?
[builtins fixtures/list.pyi]
[case testCallingWithTupleVarArgs]
def f(a: 'A', b: 'B', c: 'C') -> None: pass

class A: pass
class B: pass
class C: pass
class CC(C): pass

a: A
b: B
c: C
cc: CC

f(*(a, b, b)) # E: Argument 1 to "f" has incompatible type "*tuple[A, B, B]"; expected "C"
f(*(b, b, c)) # E: Argument 1 to "f" has incompatible type "*tuple[B, B, C]"; expected "A"
f(a, *(b, b)) # E: Argument 2 to "f" has incompatible type "*tuple[B, B]"; expected "C"
f(b, *(b, c)) # E: Argument 1 to "f" has incompatible type "B"; expected "A"
f(*(a, b))    # E: Missing positional arguments "b", "c" in call to "f"
f(*(a, b, c, c)) # E: Too many arguments for "f"
f(a, *(b, c, c)) # E: Too many arguments for "f"
f(*(a, b, c))
f(a, *(b, c))
f(a, b, *(c,))
f(a, *(b, cc))
[builtins fixtures/tuple.pyi]

[case testInvalidVarArg]
from typing import Any

def f(a: 'A') -> None:
    pass

class A: pass

a = A()

f(*None)  # E: Expected iterable as variadic argument
f(*a)    # E: Expected iterable as variadic argument
f(*(a,))

f(*4)  # E: Expected iterable as variadic argument
f(a, *4)  # E: Expected iterable as variadic argument

def main(f: Any) -> None:
    f(*3)  # E: Expected iterable as variadic argument

[builtins fixtures/tuple.pyi]


-- Calling varargs function with varargs
-- -------------------------------------


[case testCallingVarArgsFunctionWithListVarArgs]
from typing import List

def f(a: 'A', *b: 'B') -> None: pass
def g(a: 'A', *b: 'A') -> None: pass
class A: pass
class B: pass

aa: List[A]
ab: List[B]
a: A
b: B
f(*aa)           # E: Argument 1 to "f" has incompatible type "*list[A]"; expected "B"
f(a, *aa)        # E: Argument 2 to "f" has incompatible type "*list[A]"; expected "B"
f(b, *ab)        # E: Argument 1 to "f" has incompatible type "B"; expected "A"
f(a, a, *ab)     # E: Argument 2 to "f" has incompatible type "A"; expected "B"
f(a, b, *aa)     # E: Argument 3 to "f" has incompatible type "*list[A]"; expected "B"
f(b, b, *ab)     # E: Argument 1 to "f" has incompatible type "B"; expected "A"
g(*ab)           # E: Argument 1 to "g" has incompatible type "*list[B]"; expected "A"
f(a, *ab)
f(a, b, *ab)
f(a, b, b, *ab)
g(*aa)
[builtins fixtures/list.pyi]
[case testCallingVarArgsFunctionWithTupleVarArgs]
def f(a: 'A', *b: 'B') -> None:
    pass

class A: pass
class B: pass
class C: pass
class CC(C): pass

a: A
b: B
c: C
cc: CC

f(*(b, b, b))   # E: Argument 1 to "f" has incompatible type "*tuple[B, B, B]"; expected "A"
f(*(a, a, b))   # E: Argument 1 to "f" has incompatible type "*tuple[A, A, B]"; expected "B"
f(*(a, b, a))   # E: Argument 1 to "f" has incompatible type "*tuple[A, B, A]"; expected "B"
f(a, *(a, b))   # E: Argument 2 to "f" has incompatible type "*tuple[A, B]"; expected "B"
f(b, *(b, b))   # E: Argument 1 to "f" has incompatible type "B"; expected "A"
f(b, b, *(b,))  # E: Argument 1 to "f" has incompatible type "B"; expected "A"
f(a, a, *(b,))  # E: Argument 2 to "f" has incompatible type "A"; expected "B"
f(a, b, *(a,))  # E: Argument 3 to "f" has incompatible type "*tuple[A]"; expected "B"
f(*())          # E: Too few arguments for "f"
f(*(a, b, b))
f(a, *(b, b))
f(a, b, *(b,))
[builtins fixtures/list.pyi]


-- Varargs special cases
-- ---------------------


[case testDynamicVarArg]
from typing import Any
def f(a: 'A') -> None: pass
def g(a: 'A', *b: 'A') -> None: pass
class A: pass

d: Any
a: A
f(a, a, *d) # E: Too many arguments for "f"
f(a, *d)    # Ok
f(*d)       # Ok

g(*d)
g(a, *d)
g(a, a, *d)
[builtins fixtures/list.pyi]

[case testListVarArgsAndSubtyping]
from typing import List
def f( *a: 'A') -> None:
    pass

def g( *a: 'B') -> None:
    pass

class A: pass
class B(A): pass

aa: List[A]
ab: List[B]

g(*aa) # E: Argument 1 to "g" has incompatible type "*list[A]"; expected "B"
f(*aa)
f(*ab)
g(*ab)
[builtins fixtures/list.pyi]

[case testCallerVarArgsAndDefaultArgs]
# flags: --implicit-optional --no-strict-optional

def f(a: 'A', b: 'B' = None, *c: 'B') -> None:
    pass

class A: pass
class B: pass

a, b = None, None # type: (A, B)
f(*())        # E: Too few arguments for "f"
f(a, *[a])    # E: Argument 2 to "f" has incompatible type "*list[A]"; expected "B | None" \
              # E: Argument 2 to "f" has incompatible type "*list[A]"; expected "B"
f(a, b, *[a]) # E: Argument 3 to "f" has incompatible type "*list[A]"; expected "B"
f(*(a, a, b)) # E: Argument 1 to "f" has incompatible type "*tuple[A, A, B]"; expected "B | None"
f(*(a,))
f(*(a, b))
f(*(a, b, b, b))
f(a, *[])
f(a, *[b])
f(a, *[b, b])
[builtins fixtures/list.pyi]

[case testVarArgsAfterKeywordArgInCall1]
# see: mypy issue #2729
def f(x: int, y: str) -> None: pass
f(x=1, *[2])
[builtins fixtures/list.pyi]
[out]
main:3: error: "f" gets multiple values for keyword argument "x"
main:3: error: Argument 1 to "f" has incompatible type "*list[int]"; expected "str"

[case testVarArgsAfterKeywordArgInCall2]
# see: mypy issue #2729
def f(x: int, y: str) -> None: pass
f(y='x', *[1])
[builtins fixtures/list.pyi]
[out]
main:3: error: "f" gets multiple values for keyword argument "y"
main:3: error: Argument 1 to "f" has incompatible type "*list[int]"; expected "str"

[case testVarArgsAfterKeywordArgInCall3]
def f(x: int, y: str) -> None: pass
f(y='x', *(1,))
[builtins fixtures/list.pyi]

[case testVarArgsAfterKeywordArgInCall4]
def f(x: int, *, y: str) -> None: pass
f(y='x', *[1])
[builtins fixtures/list.pyi]

[case testVarArgsAfterKeywordArgInCall5]
def f(x: int, *, y: str) -> None: pass
f(y='x', *(1,))
[builtins fixtures/list.pyi]

[case testVarArgsEmptyList]
from typing import List

def foo() -> None:
    pass

lst: List[int] = []
foo(*lst)
[builtins fixtures/list.pyi]

[case testVarArgsEmptyTuple]
def foo() -> None:
    pass

foo(*())
[builtins fixtures/tuple.pyi]

-- Overloads + varargs
-- -------------------


[case testIntersectionTypesAndVarArgs]
# flags: --no-strict-optional
from foo import *
[file foo.pyi]
from typing import overload
a, b = None, None # type: (A, B)

if int():
    b = f()        # E: Incompatible types in assignment (expression has type "A", variable has type "B")
if int():
    b = f(a)       # E: Incompatible types in assignment (expression has type "A", variable has type "B")
if int():
    b = f(a, b)    # E: Incompatible types in assignment (expression has type "A", variable has type "B")
if int():
    a = f(b)       # E: Incompatible types in assignment (expression has type "B", variable has type "A")
if int():
    a = f(b, b)    # E: Incompatible types in assignment (expression has type "B", variable has type "A")
if int():
    b = f(a, *[b]) # E: Incompatible types in assignment (expression has type "A", variable has type "B")
if int():
    b = f(*())     # E: Incompatible types in assignment (expression has type "A", variable has type "B")
if int():
    b = f(*(a,))   # E: Incompatible types in assignment (expression has type "A", variable has type "B")
if int():
    b = f(*(a, b)) # E: Incompatible types in assignment (expression has type "A", variable has type "B")
if int():
    a = f(*(b,))   # E: Incompatible types in assignment (expression has type "B", variable has type "A")
if int():
    a = f(*(b, b)) # E: Incompatible types in assignment (expression has type "B", variable has type "A")
if int():
    a = f(*[b])    # E: Incompatible types in assignment (expression has type "B", variable has type "A")

a = f()
a = f(a)
a = f(a, b)
b = f(b)
b = f(b, b)
a = f(a, *[b])
a = f(*())
a = f(*(a,))
a = f(*(a, b))
b = f(*(b,))
b = f(*(b, b))
b = f(*[b])

class A: pass
class B: pass

@overload
def f(a: A = None, *b: B) -> A: pass

@overload
def f(a: B, *b: B) -> B: pass
[builtins fixtures/list.pyi]


-- Caller varargs + type inference
-- -------------------------------


[case testCallerVarArgsListWithTypeInference]
from typing import List, TypeVar, Tuple
S = TypeVar('S')
T = TypeVar('T')

def f(a: S, *b: T) -> Tuple[S, T]:
    pass

class A: pass
class B: pass

a: A
b: B
aa: List[A]

if int():
    a, b = f(*aa)    # E: Argument 1 to "f" has incompatible type "*list[A]"; expected "B"
if int():
    b, b = f(*aa)    # E: Argument 1 to "f" has incompatible type "*list[A]"; expected "B"
if int():
    a, a = f(b, *aa) # E: Argument 1 to "f" has incompatible type "B"; expected "A"
if int():
    b, b = f(b, *aa) # E: Argument 2 to "f" has incompatible type "*list[A]"; expected "B"
if int():
    b, b = f(b, b, *aa) # E: Argument 3 to "f" has incompatible type "*list[A]"; expected "B"
if int():
    a, b = f(a, *a)  # E: Expected iterable as variadic argument
if int():
    a, b = f(*a)     # E: Expected iterable as variadic argument

if int():
    a, a = f(*aa)
if int():
    b, a = f(b, *aa)
if int():
    b, a = f(b, a, *aa)
[builtins fixtures/list.pyi]

[case testCallerVarArgsTupleWithTypeInference]
from typing import TypeVar, Tuple
S = TypeVar('S')
T = TypeVar('T')

def f(a: S, b: T) -> Tuple[S, T]: pass

class A: pass
class B: pass

a: A
b: B

if int():
    a, a = f(*(a, b))   # E: Argument 1 to "f" has incompatible type "*tuple[A, B]"; expected "A"
if int():
    b, b = f(a, *(b,))  # E: Argument 1 to "f" has incompatible type "A"; expected "B"
if int():
    a, a = f(*(a, b))   # E: Argument 1 to "f" has incompatible type "*tuple[A, B]"; expected "A"
if int():
    b, b = f(a, *(b,))  # E: Argument 1 to "f" has incompatible type "A"; expected "B"
if int():
    a, b = f(*(a, b, b)) # E: Too many arguments for "f"
if int():
    a, b = f(*(a, b))
if int():
    a, b = f(a, *(b,))
[builtins fixtures/list.pyi]

[case testCallerVarargsAndComplexTypeInference]
from typing import List, TypeVar, Generic, Tuple
T = TypeVar('T')
S = TypeVar('S')
a: A
b: B
ao: List[object]
aa: List[A]
ab: List[B]

class G(Generic[T]):
    def f(self, *a: S) -> Tuple[List[S], List[T]]:
        pass

class A: pass
class B: pass

if int():
    a, aa = G().f(*[a]) # E: Incompatible types in assignment (expression has type "list[A]", variable has type "A")
if int():
    aa, a = G().f(*[a]) # E: Incompatible types in assignment (expression has type "list[Never]", variable has type "A")
if int():
    ab, aa = G().f(*[a]) # E: Argument 1 to "f" of "G" has incompatible type "*list[A]"; expected "B"
if int():
    ao, ao = G().f(*[a])
if int():
    aa, aa = G().f(*[a])
[builtins fixtures/list.pyi]

[case testCallerTupleVarArgsAndGenericCalleeVarArg]
from typing import TypeVar

T = TypeVar('T')

def f(*args: T) -> T: ...
reveal_type(f(*(1, None)))  # N: Revealed type is "Literal[1]? | None"
reveal_type(f(1, *(None, 1)))  # N: Revealed type is "Literal[1]? | None"
reveal_type(f(1, *(1, None)))  # N: Revealed type is "Literal[1]? | None"
[builtins fixtures/tuple.pyi]


-- Comment signatures
-- ------------------


[case testVarArgsAndCommentSignature]
import typing
def f(*x): # type: (*int) -> None
    pass
f(1)
f(1, 2)
f('') # E: Argument 1 to "f" has incompatible type "str"; expected "int"
f(1, '') # E: Argument 2 to "f" has incompatible type "str"; expected "int"
[builtins fixtures/list.pyi]


-- Subtyping
-- ---------


[case testVarArgsFunctionSubtyping]
from typing import Callable
x: Callable[[int], None]
def f(*x: int) -> None: pass
def g(*x: str) -> None: pass
x = f
x = g # E: Incompatible types in assignment (expression has type "def g(*x: str) -> None", variable has type "Callable[[int], None]")
[builtins fixtures/list.pyi]
[out]


-- Decorated method where self is implied by *args
-- -----------------------------------------------

[case testVarArgsCallableSelf]
from typing import Callable
def cm(func) -> Callable[..., None]: pass
class C:
    @cm
    def foo(self) -> None: pass
C().foo()
C().foo(1)  # The decorator's return type says this should be okay

[case testInvariantDictArgNote]
from typing import Dict, Sequence
def f(x: Dict[str, Sequence[int]]) -> None: pass
def g(x: Dict[str, float]) -> None: pass
def h(x: Dict[str, int]) -> None: pass
a = {'a': [1, 2]}
b = {'b': ['c', 'd']}
c = {'c': 1.0}
d = {'d': 1}
f(a) # E: Argument 1 to "f" has incompatible type "dict[str, list[int]]"; expected "dict[str, Sequence[int]]" \
     # N: "dict" is invariant -- see https://mypy.readthedocs.io/en/stable/common_issues.html#variance \
     # N: Consider using "Mapping" instead, which is covariant in the value type
f(b) # E: Argument 1 to "f" has incompatible type "dict[str, list[str]]"; expected "dict[str, Sequence[int]]"
g(c)
g(d) # E: Argument 1 to "g" has incompatible type "dict[str, int]"; expected "dict[str, float]" \
     # N: "dict" is invariant -- see https://mypy.readthedocs.io/en/stable/common_issues.html#variance \
     # N: Consider using "Mapping" instead, which is covariant in the value type
h(c) # E: Argument 1 to "h" has incompatible type "dict[str, float]"; expected "dict[str, int]"
h(d)
[builtins fixtures/dict.pyi]
[typing fixtures/typing-medium.pyi]

[case testInvariantListArgNote]
from typing import List, Union
def f(numbers: List[Union[int, float]]) -> None: pass
a = [1, 2]
f(a) # E: Argument 1 to "f" has incompatible type "list[int]"; expected "list[int | float]" \
     # N: "list" is invariant -- see https://mypy.readthedocs.io/en/stable/common_issues.html#variance \
     # N: Consider using "Sequence" instead, which is covariant
x = [1]
y = ['a']
if int():
    x = y # E: Incompatible types in assignment (expression has type "list[str]", variable has type "list[int]")
[builtins fixtures/list.pyi]

[case testInvariantTypeConfusingNames]
from typing import TypeVar
class Listener: pass
class DictReader: pass
def f(x: Listener) -> None: pass
def g(y: DictReader) -> None: pass
a = [1, 2]
b = {'b': 1}
f(a) # E: Argument 1 to "f" has incompatible type "list[int]"; expected "Listener"
g(b) # E: Argument 1 to "g" has incompatible type "dict[str, int]"; expected "DictReader"
[builtins fixtures/dict.pyi]

[case testInvariantTypeConfusingNames2]
from typing import Iterable, Generic, TypeVar, List

T = TypeVar('T')

class I(Iterable[T]):
    ...

class Bad(Generic[T]):
    ...

def bar(*args: float) -> float:
    ...

good1: Iterable[float]
good2: List[float]
good3: I[float]
bad1: I[str]
bad2: Bad[float]
bar(*good1)
bar(*good2)
bar(*good3)
bar(*bad1)  # E: Argument 1 to "bar" has incompatible type "*I[str]"; expected "float"
bar(*bad2)  # E: Expected iterable as variadic argument
[builtins fixtures/dict.pyi]

-- Keyword arguments unpacking

[case testUnpackKwargsReveal]
from typing import TypedDict
from typing_extensions import Unpack

class Person(TypedDict):
    name: str
    age: int
def foo(arg: bool, **kwargs: Unpack[Person]) -> None: ...

reveal_type(foo)  # N: Revealed type is "def (arg: builtins.bool, **kwargs: Unpack[TypedDict('__main__.Person', {'name': builtins.str, 'age': builtins.int})])"
[builtins fixtures/dict.pyi]
[typing fixtures/typing-typeddict.pyi]

[case testUnpackOutsideOfKwargs]
from typing import TypedDict
from typing_extensions import Unpack
class Person(TypedDict):
    name: str
    age: int

def foo(x: Unpack[Person]) -> None:  # E: Unpack is only valid in a variadic position
    ...
def bar(x: int, *args: Unpack[Person]) -> None:  # E: "Person" cannot be unpacked (must be tuple or TypeVarTuple)
    ...
def baz(**kwargs: Unpack[Person]) -> None:  # OK
    ...
[builtins fixtures/dict.pyi]
[typing fixtures/typing-typeddict.pyi]

[case testUnpackWithoutTypedDict]
from typing_extensions import Unpack

def foo(**kwargs: Unpack[dict]) -> None:  # E: Unpack item in ** parameter must be a TypedDict
    ...
[builtins fixtures/dict.pyi]

[case testUnpackWithDuplicateKeywords]
from typing import TypedDict
from typing_extensions import Unpack

class Person(TypedDict):
    name: str
    age: int
def foo(name: str, **kwargs: Unpack[Person]) -> None:  # E: Overlap between parameter names and ** TypedDict items: "name"
    ...
[builtins fixtures/dict.pyi]
[typing fixtures/typing-typeddict.pyi]

[case testUnpackWithDuplicateKeywordKwargs]
from typing_extensions import Unpack
from typing import Dict, List, TypedDict

class Spec(TypedDict):
    args: List[int]
    kwargs: Dict[int, int]
def foo(**kwargs: Unpack[Spec]) -> None:  # Allowed
    ...
foo(args=[1], kwargs={"2": 3})  # E: Dict entry 0 has incompatible type "str": "int"; expected "int": "int"
[builtins fixtures/dict.pyi]
[typing fixtures/typing-typeddict.pyi]

[case testUnpackKwargsNonIdentifier]
from typing import TypedDict
from typing_extensions import Unpack

Weird = TypedDict("Weird", {"@": int})

def foo(**kwargs: Unpack[Weird]) -> None:
    reveal_type(kwargs["@"])  # N: Revealed type is "builtins.int"
foo(**{"@": 42})
foo(**{"no": "way"})  # E: Argument 1 to "foo" has incompatible type "**dict[str, str]"; expected "int"
[builtins fixtures/dict.pyi]
[typing fixtures/typing-typeddict.pyi]

[case testUnpackKwargsEmpty]
from typing import TypedDict
from typing_extensions import Unpack

Empty = TypedDict("Empty", {})

def foo(**kwargs: Unpack[Empty]) -> None:
    reveal_type(kwargs)  # N: Revealed type is "TypedDict('__main__.Empty', {})"
foo()
foo(x=1)  # E: Unexpected keyword argument "x" for "foo"
[builtins fixtures/dict.pyi]
[typing fixtures/typing-typeddict.pyi]

[case testUnpackTypedDictTotality]
from typing import TypedDict
from typing_extensions import Unpack

class Circle(TypedDict, total=True):
    radius: int
    color: str
    x: int
    y: int

def foo(**kwargs: Unpack[Circle]):
    ...
foo(x=0, y=0, color='orange')  # E: Missing named argument "radius" for "foo"

class Square(TypedDict, total=False):
    side: int
    color: str

def bar(**kwargs: Unpack[Square]):
    ...
bar(side=12)
[builtins fixtures/dict.pyi]
[typing fixtures/typing-typeddict.pyi]

[case testUnpackUnexpectedKeyword]
from typing import TypedDict
from typing_extensions import Unpack

class Person(TypedDict, total=False):
    name: str
    age: int

def foo(**kwargs: Unpack[Person]) -> None:
    ...
foo(name='John', age=42, department='Sales')  # E: Unexpected keyword argument "department" for "foo"
foo(name='Jennifer', age=38)
[builtins fixtures/dict.pyi]
[typing fixtures/typing-typeddict.pyi]

[case testUnpackKeywordTypes]
from typing import TypedDict
from typing_extensions import Unpack

class Person(TypedDict):
    name: str
    age: int

def foo(**kwargs: Unpack[Person]):
    ...
foo(name='John', age='42')  # E: Argument "age" to "foo" has incompatible type "str"; expected "int"
foo(name='Jennifer', age=38)
[builtins fixtures/dict.pyi]
[typing fixtures/typing-typeddict.pyi]

[case testUnpackKeywordTypesTypedDict]
from typing import TypedDict
from typing_extensions import Unpack

class Person(TypedDict):
    name: str
    age: int

class LegacyPerson(TypedDict):
    name: str
    age: str

def foo(**kwargs: Unpack[Person]) -> None:
    ...
lp = LegacyPerson(name="test", age="42")
foo(**lp)  # E: Argument "age" to "foo" has incompatible type "str"; expected "int"
[builtins fixtures/dict.pyi]
[typing fixtures/typing-typeddict.pyi]

[case testFunctionBodyWithUnpackedKwargs]
from typing import TypedDict
from typing_extensions import Unpack

class Person(TypedDict):
    name: str
    age: int

def foo(**kwargs: Unpack[Person]) -> int:
    name: str = kwargs['name']
    age: str = kwargs['age']  # E: Incompatible types in assignment (expression has type "int", variable has type "str")
    department: str = kwargs['department']  # E: TypedDict "Person" has no key "department"
    return kwargs['age']
[builtins fixtures/dict.pyi]
[typing fixtures/typing-typeddict.pyi]

[case testUnpackKwargsOverrides]
from typing import TypedDict
from typing_extensions import Unpack

class Person(TypedDict):
    name: str
    age: int

class Base:
    def foo(self, **kwargs: Unpack[Person]) -> None: ...
class SubGood(Base):
    def foo(self, *, name: str, age: int, extra: bool = False) -> None: ...
class SubBad(Base):
    def foo(self, *, name: str, age: str) -> None: ...  # E: Argument 2 of "foo" is incompatible with supertype "Base"; supertype defines the argument type as "int" \
    # N: This violates the Liskov substitution principle \
    # N: See https://mypy.readthedocs.io/en/stable/common_issues.html#incompatible-overrides
[builtins fixtures/dict.pyi]
[typing fixtures/typing-typeddict.pyi]

[case testUnpackKwargsOverridesTypedDict]
from typing import TypedDict
from typing_extensions import Unpack

class Person(TypedDict):
    name: str
    age: int

class PersonExtra(Person, total=False):
    extra: bool

class Unrelated(TypedDict):
    baz: int

class Base:
    def foo(self, **kwargs: Unpack[Person]) -> None: ...
class SubGood(Base):
    def foo(self, **kwargs: Unpack[PersonExtra]) -> None: ...
class SubBad(Base):
    def foo(self, **kwargs: Unpack[Unrelated]) -> None: ...  # E: Signature of "foo" incompatible with supertype "Base" \
    # N:      Superclass: \
    # N:          def foo(*, name: str, age: int) -> None \
    # N:      Subclass: \
    # N:          def foo(self, *, baz: int) -> None
[builtins fixtures/dict.pyi]
[typing fixtures/typing-typeddict.pyi]

[case testUnpackKwargsGeneric]
from typing import Generic, TypedDict, TypeVar
from typing_extensions import Unpack

T = TypeVar("T")
class Person(TypedDict, Generic[T]):
    name: str
    value: T

def foo(**kwargs: Unpack[Person[T]]) -> T: ...
reveal_type(foo(name="test", value=42))  # N: Revealed type is "builtins.int"
[builtins fixtures/dict.pyi]
[typing fixtures/typing-typeddict.pyi]

[case testUnpackKwargsInference]
from typing import Generic, TypedDict, TypeVar, Protocol
from typing_extensions import Unpack

T_contra = TypeVar("T_contra", contravariant=True)
class CBPerson(Protocol[T_contra]):
    def __call__(self, **kwargs: Unpack[Person[T_contra]]) -> None: ...

T = TypeVar("T")
class Person(TypedDict, Generic[T]):
    name: str
    value: T

def test(cb: CBPerson[T]) -> T: ...

def foo(*, name: str, value: int) -> None: ...
reveal_type(test(foo))  # N: Revealed type is "builtins.int"
[builtins fixtures/dict.pyi]
[typing fixtures/typing-typeddict.pyi]

[case testUnpackKwargsOverload]
from typing import TypedDict, Any, overload
from typing_extensions import Unpack

class Person(TypedDict):
    name: str
    age: int

class Fruit(TypedDict):
    sort: str
    taste: int

@overload
def foo(**kwargs: Unpack[Person]) -> int: ...
@overload
def foo(**kwargs: Unpack[Fruit]) -> str: ...
def foo(**kwargs: Any) -> Any:
    ...

reveal_type(foo(sort="test", taste=999))  # N: Revealed type is "builtins.str"
[builtins fixtures/dict.pyi]
[typing fixtures/typing-typeddict.pyi]

[case testUnpackKwargsJoin]
from typing import TypedDict
from typing_extensions import Unpack

class Person(TypedDict):
    name: str
    age: int

def foo(*, name: str, age: int) -> None: ...
def bar(**kwargs: Unpack[Person]) -> None: ...

reveal_type([foo, bar])  # N: Revealed type is "builtins.list[def (*, name: builtins.str, age: builtins.int)]"
reveal_type([bar, foo])  # N: Revealed type is "builtins.list[def (*, name: builtins.str, age: builtins.int)]"
[builtins fixtures/dict.pyi]
[typing fixtures/typing-typeddict.pyi]

[case testUnpackKwargsParamSpec]
from typing import Callable, Any, TypedDict, TypeVar, List
from typing_extensions import ParamSpec, Unpack

class Person(TypedDict):
    name: str
    age: int

P = ParamSpec('P')
T = TypeVar('T')

def dec(f: Callable[P, T]) -> Callable[P, List[T]]: ...

@dec
def g(**kwargs: Unpack[Person]) -> int: ...

reveal_type(g)  # N: Revealed type is "def (*, name: builtins.str, age: builtins.int) -> builtins.list[builtins.int]"
[builtins fixtures/dict.pyi]
[typing fixtures/typing-typeddict.pyi]

[case testUnpackGenericTypedDictImplicitAnyEnabled]
from typing import Generic, TypedDict, TypeVar
from typing_extensions import Unpack

T = TypeVar("T")
class TD(TypedDict, Generic[T]):
    key: str
    value: T

def foo(**kwds: Unpack[TD]) -> None: ...  # Same as `TD[Any]`
foo(key="yes", value=42)
foo(key="yes", value="ok")
[builtins fixtures/dict.pyi]
[typing fixtures/typing-typeddict.pyi]

[case testUnpackGenericTypedDictImplicitAnyDisabled]
# flags: --disallow-any-generics
from typing import Generic, TypedDict, TypeVar
from typing_extensions import Unpack

T = TypeVar("T")
class TD(TypedDict, Generic[T]):
    key: str
    value: T

def foo(**kwds: Unpack[TD]) -> None: ...  # E: Missing type arguments for generic type "TD"
foo(key="yes", value=42)
foo(key="yes", value="ok")
[builtins fixtures/dict.pyi]
[typing fixtures/typing-typeddict.pyi]

[case testUnpackNoCrashOnEmpty]
from typing_extensions import Unpack

class C:
    def __init__(self, **kwds: Unpack) -> None: ...  # E: Unpack[...] requires exactly one type argument
class D:
    def __init__(self, **kwds: Unpack[int, str]) -> None: ...  # E: Unpack[...] requires exactly one type argument
[builtins fixtures/dict.pyi]

[case testUnpackInCallableType]
# flags: --python-version 3.11
from typing import Callable, TypedDict
from typing_extensions import Unpack

class TD(TypedDict):
    key: str
    value: str

foo: Callable[[Unpack[TD]], None]
foo(key="yes", value=42)  # E: Argument "value" has incompatible type "int"; expected "str"
foo(key="yes", value="ok")

bad: Callable[[*TD], None]  # E: "TD" cannot be unpacked (must be tuple or TypeVarTuple)
[builtins fixtures/dict.pyi]
[typing fixtures/typing-typeddict.pyi]