117 lines
3.6 KiB
Python
117 lines
3.6 KiB
Python
# Copyright (C) Dnspython Contributors, see LICENSE for text of ISC license
|
|
|
|
# Copyright (C) 2003-2017 Nominum, Inc.
|
|
#
|
|
# Permission to use, copy, modify, and distribute this software and its
|
|
# documentation for any purpose with or without fee is hereby granted,
|
|
# provided that the above copyright notice and this permission notice
|
|
# appear in all copies.
|
|
#
|
|
# THE SOFTWARE IS PROVIDED "AS IS" AND NOMINUM DISCLAIMS ALL WARRANTIES
|
|
# WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
|
|
# MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL NOMINUM BE LIABLE FOR
|
|
# ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
|
|
# WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
|
|
# ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT
|
|
# OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
|
|
|
|
import enum
|
|
from typing import Type, TypeVar, Union
|
|
|
|
TIntEnum = TypeVar("TIntEnum", bound="IntEnum")
|
|
|
|
|
|
class IntEnum(enum.IntEnum):
|
|
@classmethod
|
|
def _missing_(cls, value):
|
|
cls._check_value(value)
|
|
val = int.__new__(cls, value)
|
|
val._name_ = cls._extra_to_text(value, None) or f"{cls._prefix()}{value}"
|
|
val._value_ = value
|
|
return val
|
|
|
|
@classmethod
|
|
def _check_value(cls, value):
|
|
max = cls._maximum()
|
|
if not isinstance(value, int):
|
|
raise TypeError
|
|
if value < 0 or value > max:
|
|
name = cls._short_name()
|
|
raise ValueError(f"{name} must be an int between >= 0 and <= {max}")
|
|
|
|
@classmethod
|
|
def from_text(cls: Type[TIntEnum], text: str) -> TIntEnum:
|
|
text = text.upper()
|
|
try:
|
|
return cls[text]
|
|
except KeyError:
|
|
pass
|
|
value = cls._extra_from_text(text)
|
|
if value:
|
|
return value
|
|
prefix = cls._prefix()
|
|
if text.startswith(prefix) and text[len(prefix) :].isdigit():
|
|
value = int(text[len(prefix) :])
|
|
cls._check_value(value)
|
|
try:
|
|
return cls(value)
|
|
except ValueError:
|
|
return value
|
|
raise cls._unknown_exception_class()
|
|
|
|
@classmethod
|
|
def to_text(cls: Type[TIntEnum], value: int) -> str:
|
|
cls._check_value(value)
|
|
try:
|
|
text = cls(value).name
|
|
except ValueError:
|
|
text = None
|
|
text = cls._extra_to_text(value, text)
|
|
if text is None:
|
|
text = f"{cls._prefix()}{value}"
|
|
return text
|
|
|
|
@classmethod
|
|
def make(cls: Type[TIntEnum], value: Union[int, str]) -> TIntEnum:
|
|
"""Convert text or a value into an enumerated type, if possible.
|
|
|
|
*value*, the ``int`` or ``str`` to convert.
|
|
|
|
Raises a class-specific exception if a ``str`` is provided that
|
|
cannot be converted.
|
|
|
|
Raises ``ValueError`` if the value is out of range.
|
|
|
|
Returns an enumeration from the calling class corresponding to the
|
|
value, if one is defined, or an ``int`` otherwise.
|
|
"""
|
|
|
|
if isinstance(value, str):
|
|
return cls.from_text(value)
|
|
cls._check_value(value)
|
|
return cls(value)
|
|
|
|
@classmethod
|
|
def _maximum(cls):
|
|
raise NotImplementedError # pragma: no cover
|
|
|
|
@classmethod
|
|
def _short_name(cls):
|
|
return cls.__name__.lower()
|
|
|
|
@classmethod
|
|
def _prefix(cls):
|
|
return ""
|
|
|
|
@classmethod
|
|
def _extra_from_text(cls, text): # pylint: disable=W0613
|
|
return None
|
|
|
|
@classmethod
|
|
def _extra_to_text(cls, value, current_text): # pylint: disable=W0613
|
|
return current_text
|
|
|
|
@classmethod
|
|
def _unknown_exception_class(cls):
|
|
return ValueError
|