Merge branch 'master' into 2020-06-11-raise-from

1 files changed, 34 insertions, 0 deletions

diff --git a/setuptools/distutils_patch.py b/setuptools/distutils_patch.py
new file mode 100644
index 00000000..b2095fba
--- /dev/null
+++ b/setuptools/distutils_patch.py
@@ -0,0 +1,34 @@
+"""
+Ensure that the local copy of distutils is preferred over stdlib.
+
+See https://github.com/pypa/setuptools/issues/417#issuecomment-392298401
+for more motivation.
+"""
+
+import sys
+import re
+import importlib
+import warnings
+
+
+def clear_distutils():
+    if 'distutils' not in sys.modules:
+        return
+    warnings.warn("Setuptools is replacing distutils")
+    mods = [name for name in sys.modules if re.match(r'distutils\b', name)]
+    for name in mods:
+        del sys.modules[name]
+
+
+def ensure_local_distutils():
+    clear_distutils()
+    distutils = importlib.import_module('setuptools._distutils')
+    distutils.__name__ = 'distutils'
+    sys.modules['distutils'] = distutils
+
+    # sanity check that submodules load as expected
+    core = importlib.import_module('distutils.core')
+    assert '_distutils' in core.__file__, core.__file__
+
+
+ensure_local_distutils()