ui: support declaring path push urls as sub-options
Power users often want to apply per-path configuration options. For
example, they may want to declare an alternate URL for push operations
or declare a revset of revisions to push when `hg push` is used
(as opposed to attempting to push all revisions by default).
This patch establishes the use of sub-options (config options with
":" in the name) to declare additional behavior for paths.
New sub-options are declared by using the new ``@ui.pathsuboption``
decorator. This decorator serves multiple purposes:
* Declaring which sub-options are registered
* Declaring how a sub-option maps to an attribute on ``path``
instances (this is needed to `hg paths` can render sub-options
and values properly)
* Validation and normalization of config options to attribute
values
* Allows extensions to declare new sub-options without monkeypatching
* Allows extensions to overwrite built-in behavior for sub-option
handling
As convenient as the new option registration decorator is, extensions
(and even core functionality) may still need an additional hook point
to perform finalization of path instances. For example, they may wish
to validate that multiple options/attributes aren't conflicting with
each other. This hook point could be added later, if needed.
To prove this new functionality works, we implement the "pushurl"
path sub-option. This option declares the URL that `hg push` should
use by default.
We require that "pushurl" is an actual URL. This requirement might be
controversial and could be dropped if there is opposition. However,
objectors should read the complicated code in ui.path.__init__ and
commands.push for resolving non-URL values before making a judgement.
We also don't allow #fragment in the URLs. I intend to introduce a
":pushrev" (or similar) option to define a revset to control which
revisions are pushed when "-r <rev>" isn't passed into `hg push`.
This is much more powerful than #fragment and I don't think #fragment
is useful enough to continue supporting.
The [paths] section of the "config" help page has been updated
significantly. `hg paths` has been taught to display path sub-options.
The docs mention that "default-push" is now deprecated. However, there
are several references to it that need to be cleaned up. A large part
of this is converting more consumers to the new paths API. This will
happen naturally as more path sub-options are added and more and more
components need to access them.
# __init__.py - Startup and module loading logic for Mercurial.
#
# Copyright 2015 Gregory Szorc <gregory.szorc@gmail.com>
#
# This software may be used and distributed according to the terms of the
# GNU General Public License version 2 or any later version.
from __future__ import absolute_import
import imp
import os
import sys
import zipimport
__all__ = []
# Rules for how modules can be loaded. Values are:
#
# c - require C extensions
# allow - allow pure Python implementation when C loading fails
# py - only load pure Python modules
modulepolicy = '@MODULELOADPOLICY@'
# By default, require the C extensions for performance reasons.
if modulepolicy == '@' 'MODULELOADPOLICY' '@':
modulepolicy = 'c'
# PyPy doesn't load C extensions.
#
# The canonical way to do this is to test platform.python_implementation().
# But we don't import platform and don't bloat for it here.
if '__pypy__' in sys.builtin_module_names:
modulepolicy = 'py'
# Environment variable can always force settings.
modulepolicy = os.environ.get('HGMODULEPOLICY', modulepolicy)
# Modules that have both Python and C implementations. See also the
# set of .py files under mercurial/pure/.
_dualmodules = set([
'mercurial.base85',
'mercurial.bdiff',
'mercurial.diffhelpers',
'mercurial.mpatch',
'mercurial.osutil',
'mercurial.parsers',
])
class hgimporter(object):
"""Object that conforms to import hook interface defined in PEP-302."""
def find_module(self, name, path=None):
# We only care about modules that have both C and pure implementations.
if name in _dualmodules:
return self
return None
def load_module(self, name):
mod = sys.modules.get(name, None)
if mod:
return mod
mercurial = sys.modules['mercurial']
# The zip importer behaves sufficiently differently from the default
# importer to warrant its own code path.
loader = getattr(mercurial, '__loader__', None)
if isinstance(loader, zipimport.zipimporter):
def ziploader(*paths):
"""Obtain a zipimporter for a directory under the main zip."""
path = os.path.join(loader.archive, *paths)
zl = sys.path_importer_cache.get(path)
if not zl:
zl = zipimport.zipimporter(path)
return zl
try:
if modulepolicy == 'py':
raise ImportError()
zl = ziploader('mercurial')
mod = zl.load_module(name)
# Unlike imp, ziploader doesn't expose module metadata that
# indicates the type of module. So just assume what we found
# is OK (even though it could be a pure Python module).
except ImportError:
if modulepolicy == 'c':
raise
zl = ziploader('mercurial', 'pure')
mod = zl.load_module(name)
sys.modules[name] = mod
return mod
# Unlike the default importer which searches special locations and
# sys.path, we only look in the directory where "mercurial" was
# imported from.
# imp.find_module doesn't support submodules (modules with ".").
# Instead you have to pass the parent package's __path__ attribute
# as the path argument.
stem = name.split('.')[-1]
try:
if modulepolicy == 'py':
raise ImportError()
modinfo = imp.find_module(stem, mercurial.__path__)
# The Mercurial installer used to copy files from
# mercurial/pure/*.py to mercurial/*.py. Therefore, it's possible
# for some installations to have .py files under mercurial/*.
# Loading Python modules when we expected C versions could result
# in a) poor performance b) loading a version from a previous
# Mercurial version, potentially leading to incompatibility. Either
# scenario is bad. So we verify that modules loaded from
# mercurial/* are C extensions. If the current policy allows the
# loading of .py modules, the module will be re-imported from
# mercurial/pure/* below.
if modinfo[2][2] != imp.C_EXTENSION:
raise ImportError('.py version of %s found where C '
'version should exist' % name)
except ImportError:
if modulepolicy == 'c':
raise
# Could not load the C extension and pure Python is allowed. So
# try to load them.
from . import pure
modinfo = imp.find_module(stem, pure.__path__)
if not modinfo:
raise ImportError('could not find mercurial module %s' %
name)
mod = imp.load_module(name, *modinfo)
sys.modules[name] = mod
return mod
# We automagically register our custom importer as a side-effect of loading.
# This is necessary to ensure that any entry points are able to import
# mercurial.* modules without having to perform this registration themselves.
if not any(isinstance(x, hgimporter) for x in sys.meta_path):
# meta_path is used before any implicit finders and before sys.path.
sys.meta_path.insert(0, hgimporter())