Minature python library which formats bytes for user display

byte_format.py

from decimal import Decimal
from enum import IntEnum
from numbers import Real


class ByteUnit(IntEnum):
    BYTE = 1
    KILLIBYTE = 1024**1
    MEGABYTE = 1024**2
    GIGABYTE = 1024**3
    TERABYTE = 1024**4

    def __str__(self):
        if self == ByteUnit.BYTE:
            return "B"
        else:
            return f"{self.name[0]}iB"


class FormattedBytes:
    coefficient: Real
    unit: ByteUnit
    value: int

    def __init__(self, val: int, /, unit: ByteUnit | None = None):
        assert isinstance(val, int), f"Value must be integer: {val}"
        if unit is None:
            self.value = val
            val = Decimal(val)
            unit_val: int = 1
            while val >= 1024:
                val /= 1024
                unit_val *= 1024
            self.coefficient = val
            if self.coefficient == (int_coeff := int(self.coefficient)):
                self.coefficient = int_coeff
            unit = ByteUnit(unit_val)
        else:
            self.coefficient = val
            self.value = val * int(unit)
        assert unit is not None
        self.unit = unit

    def __int__(self) -> int:
        return self.value

    def __repr__(self):
        return f"<FormattedBytes(value={self.value}): {self!s}>"

    def __str__(self) -> str:
        exact_coefficient = isinstance(self.coefficient, int)
        return format(self, "" if exact_coefficient else ".3f")

    def __format__(self, spec: str) -> str:
        return f"{self.coefficient:{spec}} {self.unit}"


__all__ = ("ByteUnit", "FormattedBytes")