simplemerge: use 3-way markers if mode=='merge3', ignoring number of labels
Before this patch, we use a combination of `mode` and `labels` to
decide which marker style to use. That's mostly my own fault because I
was the one who added the `mergediff` as a "mode" instead of adding a
separate argument for marker style. Still, let's make these arguments
more orthogonal by ignoring the number of labels when deciding which
marker style to use.
This refactoring makes it a little clearer in the simplemerge
*extension* that passing more than 2 `--label` arguments changes the
marker style.
Differential Revision: https://phab.mercurial-scm.org/D11972
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
"""