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Bug report
When you call a function with incorrect key arguments or missing a required argument, you get a TypeError. But it is not always so withdataclasses.replace(). It raises a ValueError if a keyword argument for an InitVar field is missed or if a keyword argument for a field declared with init=False is specified.
>>> from dataclasses import *>>> @dataclass... class C:... x: int... y: InitVar[int]... z: int = field(init=False, default=100)... >>> c = C(x=11, y=22)>>> replace(c, x=1)Traceback (most recent call last): File "<stdin>", line 1, in <module> File "/home/serhiy/py/cpython3.12/Lib/dataclasses.py", line 1570, in replace raise ValueError(f"InitVar {f.name!r} "ValueError: InitVar 'y' must be specified with replace()>>> replace(c, x=1, y=2, z=3)Traceback (most recent call last): File "<stdin>", line 1, in <module> File "/home/serhiy/py/cpython3.12/Lib/dataclasses.py", line 1563, in replace raise ValueError(f'field {f.name} is declared with 'ValueError: field z is declared with init=False, it cannot be specified with replace()It is not even consistent with constructors:
>>> C(x=1)Traceback (most recent call last): File "<stdin>", line 1, in <module>TypeError: C.__init__() missing 1 required positional argument: 'y'>>> C(x=1, y=2, z=3)Traceback (most recent call last): File "<stdin>", line 1, in <module>TypeError: C.__init__() got an unexpected keyword argument 'z'And it raises a TypeError for unexpected keyword arguments.
>>> replace(c, x=1, y=2, t=3)Traceback (most recent call last): File "<stdin>", line 1, in <module> File "/home/serhiy/py/cpython3.12/Lib/dataclasses.py", line 1579, in replace return obj.__class__(**changes) ^^^^^^^^^^^^^^^^^^^^^^^^TypeError: C.__init__() got an unexpected keyword argument 't'I think thatdataclasses.replace() should raise TypeError in all these cases.