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Merged
JelleZijlstra merged 1 commit into from
Apr 3, 2026
Merged

Allow more precise inference for TypeVarTuple #2237

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6 changes: 3 additions & 3 deletions conformance/results/mypy/generics_typevartuple_basic.toml
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Original file line number Diff line number Diff line change
Expand Up @@ -13,11 +13,11 @@ generics_typevartuple_basic.py:59: error: TypeVarTuple "Shape" is only valid wit
generics_typevartuple_basic.py:65: error: Unexpected keyword argument "covariant" for "TypeVarTuple" [misc]
generics_typevartuple_basic.py:66: error: Too many positional arguments for "TypeVarTuple" [misc]
generics_typevartuple_basic.py:67: error: Unexpected keyword argument "bound" for "TypeVarTuple" [misc]
generics_typevartuple_basic.py:99: error: Cannot infer value of type parameter "Shape" of "multiply" [misc]
generics_typevartuple_basic.py:100: error: Cannot infer value of type parameter "Shape" of "multiply" [misc]
generics_typevartuple_basic.py:106: error: Can only use one type var tuple in a class def [misc]
generics_typevartuple_basic.py:101: error: Cannot infer value of type parameter "Shape" of "multiply" [misc]
generics_typevartuple_basic.py:107: error: Can only use one type var tuple in a class def [misc]
"""
conformance_automated = "Fail"
errors_diff = """
Line 90: Expected 1 errors
Line 91: Expected 1 errors
"""
16 changes: 8 additions & 8 deletions conformance/results/pyrefly/generics_typevartuple_basic.toml
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Original file line number Diff line number Diff line change
Expand Up @@ -4,8 +4,8 @@ TypeVarTuple is pinned too early when calling generic function.
"""
conformance_automated = "Fail"
errors_diff = """
Line 85: Unexpected errors ['Argument `tuple[float]` is not assignable to parameter `arg2` with type `tuple[int]` in function `func2` [bad-argument-type]']
Line 89: Unexpected errors ["Argument `tuple[Literal['0']]` is not assignable to parameter `arg2` with type `tuple[int]` in function `func2` [bad-argument-type]"]
Line 86: Unexpected errors ['Argument `tuple[float]` is not assignable to parameter `arg2` with type `tuple[int]` in function `func2` [bad-argument-type]']
Line 90: Unexpected errors ["Argument `tuple[Literal['0']]` is not assignable to parameter `arg2` with type `tuple[int]` in function `func2` [bad-argument-type]"]
"""
output = """
ERROR generics_typevartuple_basic.py:42:34-43: Argument `Height` is not assignable to parameter `shape` with type `tuple[Height, Width]` in function `Array.__init__` [bad-argument-type]
Expand All @@ -18,10 +18,10 @@ ERROR generics_typevartuple_basic.py:59:24-29: `TypeVarTuple` must be unpacked [
ERROR generics_typevartuple_basic.py:65:27-41: Unexpected keyword argument `covariant` to TypeVarTuple [invalid-type-var-tuple]
ERROR generics_typevartuple_basic.py:66:27-30: Unexpected positional argument to TypeVarTuple [invalid-type-var-tuple]
ERROR generics_typevartuple_basic.py:67:27-36: Unexpected keyword argument `bound` to TypeVarTuple [invalid-type-var-tuple]
ERROR generics_typevartuple_basic.py:85:13-19: Argument `tuple[float]` is not assignable to parameter `arg2` with type `tuple[int]` in function `func2` [bad-argument-type]
ERROR generics_typevartuple_basic.py:89:13-19: Argument `tuple[Literal['0']]` is not assignable to parameter `arg2` with type `tuple[int]` in function `func2` [bad-argument-type]
ERROR generics_typevartuple_basic.py:90:15-19: Argument `tuple[Literal[0]]` is not assignable to parameter `arg2` with type `tuple[int, int]` in function `func2` [bad-argument-type]
ERROR generics_typevartuple_basic.py:99:17-18: Argument `Array[Width]` is not assignable to parameter `y` with type `Array[Height]` in function `multiply` [bad-argument-type]
ERROR generics_typevartuple_basic.py:100:17-18: Argument `Array[Height, Width]` is not assignable to parameter `y` with type `Array[Height]` in function `multiply` [bad-argument-type]
ERROR generics_typevartuple_basic.py:106:7-13: Type parameters for class may not have more than one TypeVarTuple [invalid-type-var-tuple]
ERROR generics_typevartuple_basic.py:86:13-19: Argument `tuple[float]` is not assignable to parameter `arg2` with type `tuple[int]` in function `func2` [bad-argument-type]
ERROR generics_typevartuple_basic.py:90:13-19: Argument `tuple[Literal['0']]` is not assignable to parameter `arg2` with type `tuple[int]` in function `func2` [bad-argument-type]
ERROR generics_typevartuple_basic.py:91:15-19: Argument `tuple[Literal[0]]` is not assignable to parameter `arg2` with type `tuple[int, int]` in function `func2` [bad-argument-type]
ERROR generics_typevartuple_basic.py:100:17-18: Argument `Array[Width]` is not assignable to parameter `y` with type `Array[Height]` in function `multiply` [bad-argument-type]
ERROR generics_typevartuple_basic.py:101:17-18: Argument `Array[Height, Width]` is not assignable to parameter `y` with type `Array[Height]` in function `multiply` [bad-argument-type]
ERROR generics_typevartuple_basic.py:107:7-13: Type parameters for class may not have more than one TypeVarTuple [invalid-type-var-tuple]
"""
14 changes: 7 additions & 7 deletions conformance/results/pyright/generics_typevartuple_basic.toml
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Original file line number Diff line number Diff line change
Expand Up @@ -4,7 +4,7 @@ Does not correctly solve TypeVarTuple with heterogeneous bounds.
"""
conformance_automated = "Fail"
errors_diff = """
Line 89: Unexpected errors ['generics_typevartuple_basic.py:89:14 - error: Argument of type "tuple[Literal[\\'0\\']]" cannot be assigned to parameter "arg2" of type "tuple[*Ts@func2]" in function "func2"']
Line 90: Unexpected errors ['generics_typevartuple_basic.py:90:14 - error: Argument of type "tuple[Literal[\\'0\\']]" cannot be assigned to parameter "arg2" of type "tuple[*Ts@func2]" in function "func2"']
"""
output = """
generics_typevartuple_basic.py:42:34 - error: Argument of type "Height" cannot be assigned to parameter "shape" of type "tuple[*Shape@Array]" in function "__init__"
Expand All @@ -23,17 +23,17 @@ generics_typevartuple_basic.py:65:27 - error: "covariant" is unknown parameter t
generics_typevartuple_basic.py:66:27 - error: TypeVarTuple cannot have value constraints (reportGeneralTypeIssues)
generics_typevartuple_basic.py:66:32 - error: TypeVarTuple cannot have value constraints (reportGeneralTypeIssues)
generics_typevartuple_basic.py:67:27 - error: "bound" is unknown parameter to TypeVarTuple (reportGeneralTypeIssues)
generics_typevartuple_basic.py:89:14 - error: Argument of type "tuple[Literal['0']]" cannot be assigned to parameter "arg2" of type "tuple[*Ts@func2]" in function "func2"
generics_typevartuple_basic.py:90:14 - error: Argument of type "tuple[Literal['0']]" cannot be assigned to parameter "arg2" of type "tuple[*Ts@func2]" in function "func2"
  "Literal['0']" is not assignable to "int" (reportArgumentType)
generics_typevartuple_basic.py:90:15 - error: Argument of type "tuple[Literal[0]]" cannot be assigned to parameter "arg2" of type "tuple[*Ts@func2]" in function "func2"
generics_typevartuple_basic.py:91:15 - error: Argument of type "tuple[Literal[0]]" cannot be assigned to parameter "arg2" of type "tuple[*Ts@func2]" in function "func2"
  "tuple[Literal[0]]" is not assignable to "tuple[int, int]"
    Tuple size mismatch; expected 2 but received 1 (reportArgumentType)
generics_typevartuple_basic.py:99:17 - error: Argument of type "Array[Width]" cannot be assigned to parameter "y" of type "Array[*Shape@multiply]" in function "multiply"
generics_typevartuple_basic.py:100:17 - error: Argument of type "Array[Width]" cannot be assigned to parameter "y" of type "Array[*Shape@multiply]" in function "multiply"
  "Array[Width]" is not assignable to "Array[Height]"
    Type parameter "Shape@Array" is invariant, but "*tuple[Width]" is not the same as "*tuple[Height]" (reportArgumentType)
generics_typevartuple_basic.py:100:17 - error: Argument of type "Array[Height, Width]" cannot be assigned to parameter "y" of type "Array[*Shape@multiply]" in function "multiply"
generics_typevartuple_basic.py:101:17 - error: Argument of type "Array[Height, Width]" cannot be assigned to parameter "y" of type "Array[*Shape@multiply]" in function "multiply"
  "Array[Height, Width]" is not assignable to "Array[Height]"
    Type parameter "Shape@Array" is invariant, but "*tuple[Height, Width]" is not the same as "*tuple[Height]" (reportArgumentType)
generics_typevartuple_basic.py:106:14 - error: Generic class can have at most one TypeVarTuple type parameter but received multiple ("Ts1", "Ts2") (reportGeneralTypeIssues)
generics_typevartuple_basic.py:106:29 - error: Type argument list can have at most one unpacked TypeVarTuple or tuple (reportInvalidTypeForm)
generics_typevartuple_basic.py:107:14 - error: Generic class can have at most one TypeVarTuple type parameter but received multiple ("Ts1", "Ts2") (reportGeneralTypeIssues)
generics_typevartuple_basic.py:107:29 - error: Type argument list can have at most one unpacked TypeVarTuple or tuple (reportInvalidTypeForm)
"""
10 changes: 5 additions & 5 deletions conformance/results/ty/generics_typevartuple_basic.toml
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Expand Up @@ -5,18 +5,18 @@ Line 43: Expected 1 errors
Line 53: Expected 1 errors
Line 56: Expected 1 errors
Line 59: Expected 1 errors
Line 90: Expected 1 errors
Line 99: Expected 1 errors
Line 91: Expected 1 errors
Line 100: Expected 1 errors
Line 106: Expected 1 errors
Line 101: Expected 1 errors
Line 107: Expected 1 errors
Lines 44, 45: Expected error (tag 'v6')
Line 84: Unexpected errors ['generics_typevartuple_basic.py:84:1: error[type-assertion-failure] Type `tuple[@Todo(TypeVarTuple), ...]` does not match asserted type `tuple[int]`']
Line 85: Unexpected errors ['generics_typevartuple_basic.py:85:5: error[type-assertion-failure] Type `tuple[@Todo(TypeVarTuple), ...]` does not match asserted type `tuple[int]`']
"""
output = """
generics_typevartuple_basic.py:42:34: error[invalid-argument-type] Argument to bound method `__init__` is incorrect: Expected `tuple[@Todo(TypeVarTuple), ...]`, found `Height`
generics_typevartuple_basic.py:52:14: error[invalid-generic-class] `TypeVarTuple` must be unpacked with `*` or `Unpack[]` when used as an argument to `Generic`
generics_typevartuple_basic.py:65:27: error[unknown-argument] Argument `covariant` does not match any known parameter of function `__new__`
generics_typevartuple_basic.py:66:27: error[too-many-positional-arguments] Too many positional arguments to function `__new__`: expected 2, got 4
generics_typevartuple_basic.py:67:27: error[unknown-argument] Argument `bound` does not match any known parameter of function `__new__`
generics_typevartuple_basic.py:84:1: error[type-assertion-failure] Type `tuple[@Todo(TypeVarTuple), ...]` does not match asserted type `tuple[int]`
generics_typevartuple_basic.py:85:5: error[type-assertion-failure] Type `tuple[@Todo(TypeVarTuple), ...]` does not match asserted type `tuple[int]`
"""
12 changes: 6 additions & 6 deletions conformance/results/zuban/generics_typevartuple_basic.toml
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Original file line number Diff line number Diff line change
Expand Up @@ -4,7 +4,7 @@ Does not correctly solve TypeVarTuple with heterogeneous bounds.
"""
conformance_automated = "Fail"
errors_diff = """
Line 89: Unexpected errors ['generics_typevartuple_basic.py:89: error: Argument 2 to "func2" has incompatible type "tuple[Literal[\\'0\\']]"; expected "tuple[int]" [arg-type]']
Line 90: Unexpected errors ['generics_typevartuple_basic.py:90: error: Argument 2 to "func2" has incompatible type "tuple[Literal[\\'0\\']]"; expected "tuple[int]" [arg-type]']
"""
output = """
generics_typevartuple_basic.py:42: error: Argument 1 to "Array" has incompatible type "Height"; expected "tuple[Height, Width]" [arg-type]
Expand All @@ -17,9 +17,9 @@ generics_typevartuple_basic.py:59: error: TypeVarTuple "Shape" is only valid wit
generics_typevartuple_basic.py:65: error: Unexpected keyword argument "covariant" for "TypeVarTuple" [call-arg]
generics_typevartuple_basic.py:66: error: Too many positional arguments for "TypeVarTuple" [call-arg]
generics_typevartuple_basic.py:67: error: Unexpected keyword argument "bound" for "TypeVarTuple" [call-arg]
generics_typevartuple_basic.py:89: error: Argument 2 to "func2" has incompatible type "tuple[Literal['0']]"; expected "tuple[int]" [arg-type]
generics_typevartuple_basic.py:90: error: Argument 2 to "func2" has incompatible type "tuple[Literal[0]]"; expected "tuple[int, int]" [arg-type]
generics_typevartuple_basic.py:99: error: Argument 2 to "multiply" has incompatible type "Array[Width]"; expected "Array[Height]" [arg-type]
generics_typevartuple_basic.py:100: error: Argument 2 to "multiply" has incompatible type "Array[Height, Width]"; expected "Array[Height]" [arg-type]
generics_typevartuple_basic.py:106: error: Can only use one type var tuple in a class def [misc]
generics_typevartuple_basic.py:90: error: Argument 2 to "func2" has incompatible type "tuple[Literal['0']]"; expected "tuple[int]" [arg-type]
generics_typevartuple_basic.py:91: error: Argument 2 to "func2" has incompatible type "tuple[Literal[0]]"; expected "tuple[int, int]" [arg-type]
generics_typevartuple_basic.py:100: error: Argument 2 to "multiply" has incompatible type "Array[Width]"; expected "Array[Height]" [arg-type]
generics_typevartuple_basic.py:101: error: Argument 2 to "multiply" has incompatible type "Array[Height, Width]"; expected "Array[Height]" [arg-type]
generics_typevartuple_basic.py:107: error: Can only use one type var tuple in a class def [misc]
"""
3 changes: 2 additions & 1 deletion conformance/tests/generics_typevartuple_basic.py
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Expand Up @@ -81,7 +81,8 @@ def func2(arg1: tuple[*Ts], arg2: tuple[*Ts]) -> tuple[*Ts]:
# > the types must match exactly (the list of type parameters must be the
# > same length, and the type parameters themselves must be identical)

assert_type(func2((0,), (1,)), tuple[int]) # OK
def check_func2(x: int):
assert_type(func2((x,), (1,)), tuple[int]) # OK
func2((0,), (0.0,)) # OK
func2((0.0,), (0,)) # OK
func2((0,), (1,)) # OK
Expand Down