dataclass-property 1.4.1

Add the ability to use properties with dataclasses.

Add the ability to use properties with dataclasses. This allows for better input validation on dataclasses.

Most of the code base is a direct copy from dataclasses with modifications. Unfortunately, dataclasses were not written in a way where you can extend the functionality easily. I changed the code to use a class based system, so the functionality could be extended. It’s still not fun to work with the dataclasses library.

Examples

from typing import Union
from dataclass_property import dataclass

@dataclass
class TimeDelta:
    hours: int = 0
    minutes: int = 0
    milliseconds: int = 0

    @property
    def seconds(self) -> int:  # default_factory is set to `int()` from the annotation
        return self._seconds

    @seconds.setter
    def seconds(self, value: Union[int, float]):
        if isinstance(value, float):
            mill = int((value % 1) * 1000)
            if mill:
                self.milliseconds = mill
        self._seconds = int(value)

td = TimeDelta(minutes=1)
td.seconds = 0.5
assert td.seconds == 0
assert td.milliseconds == 500

td = TimeDelta(seconds=0.1)
assert td.seconds == 0
assert td.milliseconds == 100

field_property example with custom defaults

from dataclass_property import dataclass, field_property

@dataclass
class Point:
    # X
    @field_property(default=1)
    def x(self) -> int:
        return self._x

    @x.setter
    def x(self, value: int):
        self._x = value

    # Y
    y: int = field_property(default=1)

    @y.getter
    def y(self) -> int:
        return self._y

    @y.setter
    def y(self, value: int):
        self._y = value

    # Z
    @field_property
    def z(self) -> int:
        return self._z

    z.default(5)

    @z.default_factory
    @classmethod
    def z(cls):
        return 5

    @z.setter
    def z(self, value: int):
        self._z = value

p = Point()
assert p.x == 1
assert p.y == 1
assert p.z == 5

p = Point(x=2, y=2, z=6)
assert p.x == 2
assert p.y == 2
assert p.z == 6