view mercurial/thirdparty/attr/exceptions.py @ 37045:a708e1e4d7a8

url: support suppressing Accept header

Sending this header automatically could interfere with future
testing and client behavior. Let's add a knob to disable the
behavior.

We don't have a control for User-Agent because urllib will send
it if we don't set something. I don't feel like hacking into the
bowels of urllib to figure out how to suppress that. UA shouldn't
be used for anything meaningful. So it shouldn't pose any problems
beyond non-determinism (since the header has the Mercurial version in
it).

Differential Revision: https://phab.mercurial-scm.org/D2843

from __future__ import absolute_import, division, print_function


class FrozenInstanceError(AttributeError):
    """
    A frozen/immutable instance has been attempted to be modified.

    It mirrors the behavior of ``namedtuples`` by using the same error message
    and subclassing :exc:`AttributeError`.

    .. versionadded:: 16.1.0
    """
    msg = "can't set attribute"
    args = [msg]


class AttrsAttributeNotFoundError(ValueError):
    """
    An ``attrs`` function couldn't find an attribute that the user asked for.

    .. versionadded:: 16.2.0
    """


class NotAnAttrsClassError(ValueError):
    """
    A non-``attrs`` class has been passed into an ``attrs`` function.

    .. versionadded:: 16.2.0
    """


class DefaultAlreadySetError(RuntimeError):
    """
    A default has been set using ``attr.ib()`` and is attempted to be reset
    using the decorator.

    .. versionadded:: 17.1.0
    """