dataclasses_inheritance.py

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True Positive

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TP: 0

FP: 0

FN: 2

Optional: 0 / 1

"""
Tests inheritance rules for dataclasses.
"""

# Specification: https://peps.python.org/pep-0557/#inheritance

from dataclasses import dataclass
from typing import Any, ClassVar


@dataclass
class DC1:
    a: int
    b: str = ""


@dataclass
class DC2(DC1):
    b: str = ""
    a: int = 1


dc2_1 = DC2(1, "")

dc2_2 = DC2()


@dataclass
class DC3:
    x: float = 15.0
    y: str = ""


@dataclass
class DC4(DC3):
    z: tuple[int] = (10,)
    x: float = 15


dc4_1 = DC4(0.0, "", (1,))


@dataclass
class DC5:
    # While this generates an error at runtime for the stdlib dataclass,
    # other libraries that use dataclass_transform don't have similar
    # restrictions. It is therefore not required that a type checker
    # report an error here.
    x: list[int] = []  # E?


@dataclass
class DC6:
    x: int
    y: ClassVar[int] = 1


@dataclass
class DC7(DC6):
    # This should generate an error because a ClassVar cannot override
    # an instance variable of the same name.
    x: ClassVar[int]  # E
Expected a ty diagnostic for this line

    # This should generate an error because an instance variable cannot
    # override a class variable of the same name.
    y: int  # E
Expected a ty diagnostic for this line