venv/lib/python3.11/site-packages/_distutils_hack/__init__.py

   1 # don't import any costly modules
   2 import sys
   3 import os
   4
   5
   6 is_pypy = '__pypy__' in sys.builtin_module_names
   7
   8
   9 def warn_distutils_present():
  10     if 'distutils' not in sys.modules:
  11         return
  12     if is_pypy and sys.version_info < (3, 7):
  13         # PyPy for 3.6 unconditionally imports distutils, so bypass the warning
  14         # https://foss.heptapod.net/pypy/pypy/-/blob/be829135bc0d758997b3566062999ee8b23872b4/lib-python/3/site.py#L250
  15         return
  16     import warnings
  17
  18     warnings.warn(
  19         "Distutils was imported before Setuptools, but importing Setuptools "
  20         "also replaces the `distutils` module in `sys.modules`. This may lead "
  21         "to undesirable behaviors or errors. To avoid these issues, avoid "
  22         "using distutils directly, ensure that setuptools is installed in the "
  23         "traditional way (e.g. not an editable install), and/or make sure "
  24         "that setuptools is always imported before distutils."
  25     )
  26
  27
  28 def clear_distutils():
  29     if 'distutils' not in sys.modules:
  30         return
  31     import warnings
  32
  33     warnings.warn("Setuptools is replacing distutils.")
  34     mods = [
  35         name
  36         for name in sys.modules
  37         if name == "distutils" or name.startswith("distutils.")
  38     ]
  39     for name in mods:
  40         del sys.modules[name]
  41
  42
  43 def enabled():
  44     """
  45     Allow selection of distutils by environment variable.
  46     """
  47     which = os.environ.get('SETUPTOOLS_USE_DISTUTILS', 'local')
  48     return which == 'local'
  49
  50
  51 def ensure_local_distutils():
  52     import importlib
  53
  54     clear_distutils()
  55
  56     # With the DistutilsMetaFinder in place,
  57     # perform an import to cause distutils to be
  58     # loaded from setuptools._distutils. Ref #2906.
  59     with shim():
  60         importlib.import_module('distutils')
  61
  62     # check that submodules load as expected
  63     core = importlib.import_module('distutils.core')
  64     assert '_distutils' in core.__file__, core.__file__
  65     assert 'setuptools._distutils.log' not in sys.modules
  66
  67
  68 def do_override():
  69     """
  70     Ensure that the local copy of distutils is preferred over stdlib.
  71
  72     See https://github.com/pypa/setuptools/issues/417#issuecomment-392298401
  73     for more motivation.
  74     """
  75     if enabled():
  76         warn_distutils_present()
  77         ensure_local_distutils()
  78
  79
  80 class _TrivialRe:
  81     def __init__(self, *patterns):
  82         self._patterns = patterns
  83
  84     def match(self, string):
  85         return all(pat in string for pat in self._patterns)
  86
  87
  88 class DistutilsMetaFinder:
  89     def find_spec(self, fullname, path, target=None):
  90         # optimization: only consider top level modules and those
  91         # found in the CPython test suite.
  92         if path is not None and not fullname.startswith('test.'):
  93             return
  94
  95         method_name = 'spec_for_{fullname}'.format(**locals())
  96         method = getattr(self, method_name, lambda: None)
  97         return method()
  98
  99     def spec_for_distutils(self):
 100         if self.is_cpython():
 101             return
 102
 103         import importlib
 104         import importlib.abc
 105         import importlib.util
 106
 107         try:
 108             mod = importlib.import_module('setuptools._distutils')
 109         except Exception:
 110             # There are a couple of cases where setuptools._distutils
 111             # may not be present:
 112             # - An older Setuptools without a local distutils is
 113             #   taking precedence. Ref #2957.
 114             # - Path manipulation during sitecustomize removes
 115             #   setuptools from the path but only after the hook
 116             #   has been loaded. Ref #2980.
 117             # In either case, fall back to stdlib behavior.
 118             return
 119
 120         class DistutilsLoader(importlib.abc.Loader):
 121             def create_module(self, spec):
 122                 mod.__name__ = 'distutils'
 123                 return mod
 124
 125             def exec_module(self, module):
 126                 pass
 127
 128         return importlib.util.spec_from_loader(
 129             'distutils', DistutilsLoader(), origin=mod.__file__
 130         )
 131
 132     @staticmethod
 133     def is_cpython():
 134         """
 135         Suppress supplying distutils for CPython (build and tests).
 136         Ref #2965 and #3007.
 137         """
 138         return os.path.isfile('pybuilddir.txt')
 139
 140     def spec_for_pip(self):
 141         """
 142         Ensure stdlib distutils when running under pip.
 143         See pypa/pip#8761 for rationale.
 144         """
 145         if sys.version_info >= (3, 12) or self.pip_imported_during_build():
 146             return
 147         clear_distutils()
 148         self.spec_for_distutils = lambda: None
 149
 150     @classmethod
 151     def pip_imported_during_build(cls):
 152         """
 153         Detect if pip is being imported in a build script. Ref #2355.
 154         """
 155         import traceback
 156
 157         return any(
 158             cls.frame_file_is_setup(frame) for frame, line in traceback.walk_stack(None)
 159         )
 160
 161     @staticmethod
 162     def frame_file_is_setup(frame):
 163         """
 164         Return True if the indicated frame suggests a setup.py file.
 165         """
 166         # some frames may not have __file__ (#2940)
 167         return frame.f_globals.get('__file__', '').endswith('setup.py')
 168
 169     def spec_for_sensitive_tests(self):
 170         """
 171         Ensure stdlib distutils when running select tests under CPython.
 172
 173         python/cpython#91169
 174         """
 175         clear_distutils()
 176         self.spec_for_distutils = lambda: None
 177
 178     sensitive_tests = (
 179         [
 180             'test.test_distutils',
 181             'test.test_peg_generator',
 182             'test.test_importlib',
 183         ]
 184         if sys.version_info < (3, 10)
 185         else [
 186             'test.test_distutils',
 187         ]
 188     )
 189
 190
 191 for name in DistutilsMetaFinder.sensitive_tests:
 192     setattr(
 193         DistutilsMetaFinder,
 194         f'spec_for_{name}',
 195         DistutilsMetaFinder.spec_for_sensitive_tests,
 196     )
 197
 198
 199 DISTUTILS_FINDER = DistutilsMetaFinder()
 200
 201
 202 def add_shim():
 203     DISTUTILS_FINDER in sys.meta_path or insert_shim()
 204
 205
 206 class shim:
 207     def __enter__(self):
 208         insert_shim()
 209
 210     def __exit__(self, exc, value, tb):
 211         _remove_shim()
 212
 213
 214 def insert_shim():
 215     sys.meta_path.insert(0, DISTUTILS_FINDER)
 216
 217
 218 def _remove_shim():
 219     try:
 220         sys.meta_path.remove(DISTUTILS_FINDER)
 221     except ValueError:
 222         pass
 223
 224
 225 if sys.version_info < (3, 12):
 226     # DistutilsMetaFinder can only be disabled in Python < 3.12 (PEP 632)
 227     remove_shim = _remove_shim