mercurial/utils/resourceutil.py

phases: invalidate the phases set less often on retract boundary

We already have the information to update the phase set, so we do so directly
instead of invalidating the cache.

This show a sizeable speedup in our `perf::unbundle` benchmark on the
many-draft mozilla-try repository.

### data-env-vars.name            = mozilla-try-2023-03-22-zstd-sparse-revlog
  # benchmark.name                = hg.perf.perf-unbundle
  # bin-env-vars.hg.flavor        = no-rust
  # bin-env-vars.hg.py-re2-module = default
  # benchmark.variants.issue6528  = disabled

  # benchmark.variants.revs = last-10
before: 2.055259 seconds
after:  1.887064 seconds (-8.18%)
  # benchmark.variants.revs = last-100
before: 2.409239 seconds
after:  2.222429 seconds (-7.75%)
  # benchmark.variants.revs = last-1000
before: 3.945648 seconds
after:  3.762480 seconds (-4.64%)

# resourceutil.py - utility for looking up resources
#
#  Copyright 2005 K. Thananchayan <[e-mail]>
#  Copyright 2005-2007 Olivia 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.


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 (
        hasattr(sys, "frozen")  # new py2exe
        or hasattr(sys, "importers")  # old py2exe
        or _imp.is_frozen("__main__")  # 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:
    # importlib.resources exists from Python 3.7; see fallback in except clause
    # further down
    from importlib import resources  # pytype: disable=import-error

    # Force loading of the resources module
    if hasattr(resources, 'files'):
        resources.files  # pytype: disable=module-attr
    else:
        resources.open_binary  # pytype: disable=module-attr

    # py2exe raises an AssertionError if uses importlib.resources
    if getattr(sys, "frozen", None) in ("console_exe", "windows_exe"):
        raise ImportError

except (ImportError, AttributeError):
    # importlib.resources was not found (almost definitely because we're on a
    # Python version before 3.7)

    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)


else:
    from .. import encoding

    def open_resource(package, name):
        if hasattr(resources, 'files'):
            return (
                resources.files(  # pytype: disable=module-attr
                    pycompat.sysstr(package)
                )
                .joinpath(pycompat.sysstr(name))
                .open('rb')
            )
        else:
            return resources.open_binary(  # pytype: disable=module-attr
                pycompat.sysstr(package), pycompat.sysstr(name)
            )

    def is_resource(package, name):
        return resources.is_resource(  # pytype: disable=module-attr
            pycompat.sysstr(package), encoding.strfromlocal(name)
        )

    def contents(package):
        # pytype: disable=module-attr
        for r in resources.contents(pycompat.sysstr(package)):
            # pytype: enable=module-attr
            yield encoding.strtolocal(r)