codekingpro/portable-devtools

1# don't import any costly modules2import os3import sys4 5report_url = (6    "https://github.com/pypa/setuptools/issues/new?template=distutils-deprecation.yml"7)8 9 10def warn_distutils_present():11    if 'distutils' not in sys.modules:12        return13    import warnings14 15    warnings.warn(16        "Distutils was imported before Setuptools, but importing Setuptools "17        "also replaces the `distutils` module in `sys.modules`. This may lead "18        "to undesirable behaviors or errors. To avoid these issues, avoid "19        "using distutils directly, ensure that setuptools is installed in the "20        "traditional way (e.g. not an editable install), and/or make sure "21        "that setuptools is always imported before distutils."22    )23 24 25def clear_distutils():26    if 'distutils' not in sys.modules:27        return28    import warnings29 30    warnings.warn(31        "Setuptools is replacing distutils. Support for replacing "32        "an already imported distutils is deprecated. In the future, "33        "this condition will fail. "34        f"Register concerns at {report_url}"35    )36    mods = [37        name38        for name in sys.modules39        if name == "distutils" or name.startswith("distutils.")40    ]41    for name in mods:42        del sys.modules[name]43 44 45def enabled():46    """47    Allow selection of distutils by environment variable.48    """49    which = os.environ.get('SETUPTOOLS_USE_DISTUTILS', 'local')50    if which == 'stdlib':51        import warnings52 53        warnings.warn(54            "Reliance on distutils from stdlib is deprecated. Users "55            "must rely on setuptools to provide the distutils module. "56            "Avoid importing distutils or import setuptools first, "57            "and avoid setting SETUPTOOLS_USE_DISTUTILS=stdlib. "58            f"Register concerns at {report_url}"59        )60    return which == 'local'61 62 63def ensure_local_distutils():64    import importlib65 66    clear_distutils()67 68    # With the DistutilsMetaFinder in place,69    # perform an import to cause distutils to be70    # loaded from setuptools._distutils. Ref #2906.71    with shim():72        importlib.import_module('distutils')73 74    # check that submodules load as expected75    core = importlib.import_module('distutils.core')76    assert '_distutils' in core.__file__, core.__file__77    assert 'setuptools._distutils.log' not in sys.modules78 79 80def do_override():81    """82    Ensure that the local copy of distutils is preferred over stdlib.83 84    See https://github.com/pypa/setuptools/issues/417#issuecomment-39229840185    for more motivation.86    """87    if enabled():88        warn_distutils_present()89        ensure_local_distutils()90 91 92class _TrivialRe:93    def __init__(self, *patterns) -> None:94        self._patterns = patterns95 96    def match(self, string):97        return all(pat in string for pat in self._patterns)98 99 100class DistutilsMetaFinder:101    def find_spec(self, fullname, path, target=None):102        # optimization: only consider top level modules and those103        # found in the CPython test suite.104        if path is not None and not fullname.startswith('test.'):105            return None106 107        method_name = 'spec_for_{fullname}'.format(**locals())108        method = getattr(self, method_name, lambda: None)109        return method()110 111    def spec_for_distutils(self):112        if self.is_cpython():113            return None114 115        import importlib116        import importlib.abc117        import importlib.util118 119        try:120            mod = importlib.import_module('setuptools._distutils')121        except Exception:122            # There are a couple of cases where setuptools._distutils123            # may not be present:124            # - An older Setuptools without a local distutils is125            #   taking precedence. Ref #2957.126            # - Path manipulation during sitecustomize removes127            #   setuptools from the path but only after the hook128            #   has been loaded. Ref #2980.129            # In either case, fall back to stdlib behavior.130            return None131 132        class DistutilsLoader(importlib.abc.Loader):133            def create_module(self, spec):134                mod.__name__ = 'distutils'135                return mod136 137            def exec_module(self, module):138                pass139 140        return importlib.util.spec_from_loader(141            'distutils', DistutilsLoader(), origin=mod.__file__142        )143 144    @staticmethod145    def is_cpython():146        """147        Suppress supplying distutils for CPython (build and tests).148        Ref #2965 and #3007.149        """150        return os.path.isfile('pybuilddir.txt')151 152    def spec_for_pip(self):153        """154        Ensure stdlib distutils when running under pip.155        See pypa/pip#8761 for rationale.156        """157        if sys.version_info >= (3, 12) or self.pip_imported_during_build():158            return159        clear_distutils()160        self.spec_for_distutils = lambda: None161 162    @classmethod163    def pip_imported_during_build(cls):164        """165        Detect if pip is being imported in a build script. Ref #2355.166        """167        import traceback168 169        return any(170            cls.frame_file_is_setup(frame) for frame, line in traceback.walk_stack(None)171        )172 173    @staticmethod174    def frame_file_is_setup(frame):175        """176        Return True if the indicated frame suggests a setup.py file.177        """178        # some frames may not have __file__ (#2940)179        return frame.f_globals.get('__file__', '').endswith('setup.py')180 181    def spec_for_sensitive_tests(self):182        """183        Ensure stdlib distutils when running select tests under CPython.184 185        python/cpython#91169186        """187        clear_distutils()188        self.spec_for_distutils = lambda: None189 190    sensitive_tests = (191        [192            'test.test_distutils',193            'test.test_peg_generator',194            'test.test_importlib',195        ]196        if sys.version_info < (3, 10)197        else [198            'test.test_distutils',199        ]200    )201 202 203for name in DistutilsMetaFinder.sensitive_tests:204    setattr(205        DistutilsMetaFinder,206        f'spec_for_{name}',207        DistutilsMetaFinder.spec_for_sensitive_tests,208    )209 210 211DISTUTILS_FINDER = DistutilsMetaFinder()212 213 214def add_shim():215    DISTUTILS_FINDER in sys.meta_path or insert_shim()216 217 218class shim:219    def __enter__(self) -> None:220        insert_shim()221 222    def __exit__(self, exc: object, value: object, tb: object) -> None:223        _remove_shim()224 225 226def insert_shim():227    sys.meta_path.insert(0, DISTUTILS_FINDER)228 229 230def _remove_shim():231    try:232        sys.meta_path.remove(DISTUTILS_FINDER)233    except ValueError:234        pass235 236 237if sys.version_info < (3, 12):238    # DistutilsMetaFinder can only be disabled in Python < 3.12 (PEP 632)239    remove_shim = _remove_shim240