Mercurial > hg
view mercurial/thirdparty/zope/interface/exceptions.py @ 37176:943d77fc07a3
thirdparty: vendor zope.interface 4.4.3
I've been trying to formalize interfaces for various components
of Mercurial. So far, we've been using the "abc" package. This
package is "good enough" for a lot of tasks. But it quickly
falls over. For example, if you declare an @abc.abstractproperty,
you must implement that attribute with a @property or the class
compile time checking performed by abc will complain. This often
forces you to implement dumb @property wrappers to return a
_ prefixed attribute of the sane name. That's ugly.
I've also wanted to implement automated checking that classes
conform to various interfaces and don't expose other "public"
attributes.
After doing a bit of research and asking around, the general
consensus seems to be that zope.interface is the best package for
doing interface-based programming in Python. It has built-in
support for verifying classes and objects conform to interfaces.
It allows an interface's properties to be defined during __init__.
There's even an "adapter registry" that allow you to register
interfaces and look up which classes implement them. That could
potentially be useful for places where our custom registry.py
modules currently facilitates central registrations, but at a
type level. Imagine extensions providing alternate implementations
of things like the local repository interface to allow opening
repositories with custom requirements.
Anyway, this commit vendors zope.interface 4.4.3. The contents of
the source tarball have been copied into mercurial/thirdparty/zope/
without modifications.
Test modules have been removed because they are not interesting
to us.
The LICENSE.txt file has been copied so it lives next to the
source.
The Python modules don't use relative imports. zope/__init__.py
defines a namespace package. So we'll need to modify the source
code before this package is usable inside Mercurial. This will
be done in subsequent commits.
# no-check-commit for various style failures
Differential Revision: https://phab.mercurial-scm.org/D2928
author | Gregory Szorc <gregory.szorc@gmail.com> |
---|---|
date | Wed, 21 Mar 2018 19:48:50 -0700 |
parents | |
children | 68ee61822182 |
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############################################################################## # # Copyright (c) 2002 Zope Foundation and Contributors. # All Rights Reserved. # # This software is subject to the provisions of the Zope Public License, # Version 2.1 (ZPL). A copy of the ZPL should accompany this distribution. # THIS SOFTWARE IS PROVIDED "AS IS" AND ANY AND ALL EXPRESS OR IMPLIED # WARRANTIES ARE DISCLAIMED, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED # WARRANTIES OF TITLE, MERCHANTABILITY, AGAINST INFRINGEMENT, AND FITNESS # FOR A PARTICULAR PURPOSE. # ############################################################################## """Interface-specific exceptions """ class Invalid(Exception): """A specification is violated """ class DoesNotImplement(Invalid): """ This object does not implement """ def __init__(self, interface): self.interface = interface def __str__(self): return """An object does not implement interface %(interface)s """ % self.__dict__ class BrokenImplementation(Invalid): """An attribute is not completely implemented. """ def __init__(self, interface, name): self.interface=interface self.name=name def __str__(self): return """An object has failed to implement interface %(interface)s The %(name)s attribute was not provided. """ % self.__dict__ class BrokenMethodImplementation(Invalid): """An method is not completely implemented. """ def __init__(self, method, mess): self.method=method self.mess=mess def __str__(self): return """The implementation of %(method)s violates its contract because %(mess)s. """ % self.__dict__ class InvalidInterface(Exception): """The interface has invalid contents """ class BadImplements(TypeError): """An implementation assertion is invalid because it doesn't contain an interface or a sequence of valid implementation assertions. """