view mercurial/utils/resourceutil.py @ 44544:13da36d77a3f

scmutil: add option to register summary callbacks as transaction validators

We have a list of summary callbacks which are run after the transaction is
closed to show what has changed and what not. This patch makes it possible to
register those callbacks as transaction validators so that we can show summary
before committing the transaction and prompt user to accept the changes.

The goal of this is to implement `pull --confirm`.

Differential Revision: https://phab.mercurial-scm.org/D8199

# resourceutil.py - utility for looking up resources
#
#  Copyright 2005 K. Thananchayan <[e-mail]>
#  Copyright 2005-2007 Matt Mackall <[e-mail]>
#  Copyright 2006 Vadim Gelfer <[e-mail]>
#
# 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

from .. import pycompat


def mainfrozen():
    """return True if we are a frozen executable.

    The code supports py2exe (most common, Windows only) and tools/freeze
    (portable, not much used).
    """
    return (
        pycompat.safehasattr(sys, "frozen")
        or pycompat.safehasattr(sys, "importers")  # new py2exe
        or imp.is_frozen("__main__")  # old py2exe
    )  # tools/freeze


# the location of data files matching the source code
if mainfrozen() and getattr(sys, "frozen", None) != "macosx_app":
    # executable version (py2exe) doesn't support __file__
    datapath = os.path.dirname(pycompat.sysexecutable)
    _rootpath = datapath

    # The installers store the files outside of library.zip, like
    # C:\Program Files\Mercurial\defaultrc\*.rc.  This strips the
    # leading "mercurial." off of the package name, so that these
    # pseudo resources are found in their directory next to the
    # executable.
    def _package_path(package):
        dirs = package.split(b".")
        assert dirs[0] == b"mercurial"
        return os.path.join(_rootpath, *dirs[1:])


else:
    datapath = os.path.dirname(os.path.dirname(pycompat.fsencode(__file__)))
    _rootpath = os.path.dirname(datapath)

    def _package_path(package):
        return os.path.join(_rootpath, *package.split(b"."))


try:
    from importlib import resources

    from .. import encoding

    # Force loading of the resources module
    resources.open_binary  # pytype: disable=module-attr

    def open_resource(package, name):
        return resources.open_binary(  # pytype: disable=module-attr
            pycompat.sysstr(package), pycompat.sysstr(name)
        )

    def is_resource(package, name):
        return resources.is_resource(
            pycompat.sysstr(package), encoding.strfromlocal(name)
        )

    def contents(package):
        for r in resources.contents(pycompat.sysstr(package)):
            yield encoding.strtolocal(r)


except (ImportError, AttributeError):

    def open_resource(package, name):
        path = os.path.join(_package_path(package), name)
        return open(path, "rb")

    def is_resource(package, name):
        path = os.path.join(_package_path(package), name)

        try:
            return os.path.isfile(pycompat.fsdecode(path))
        except (IOError, OSError):
            return False

    def contents(package):
        path = pycompat.fsdecode(_package_path(package))

        for p in os.listdir(path):
            yield pycompat.fsencode(p)