bpo-42136: Deprecate module_repr() as found in importlib

Doc/reference/import.rst

@@ -675,6 +675,13 @@ Here are the exact rules used:
  :meth:`~importlib.abc.Loader.module_repr` method, if defined, before
  trying either approach described above. However, the method is deprecated.
 
+.. versionchanged:: 3.10
+
+ Calling :meth:`~importlib.abc.Loader.module_repr` now occurs after trying to
+ use a module's ``__spec__`` attribute but before falling back on
+ ``__file__``. Use of :meth:`~importlib.abc.Loader.module_repr` is slated to
+ stop in Python 3.12.
+
 .. _pyc-invalidation:
 
 Cached bytecode invalidation

Doc/whatsnew/3.10.rst

@@ -1010,6 +1010,12 @@ Deprecated
  for Python 3.12.
  (Contributed by Brett Cannon in :issue:`42137`.)
 
+* :meth:`importlib.abc.Loader.module_repr`,
+ :meth:`importlib.machinery.FrozenLoader.module_repr`, and
+ :meth:`importlib.machinery.BuiltinLoader.module_repr` are deprecated and
+ slated for removal in Python 3.12.
+ (Contributed by Brett Cannon in :issue:`42136`.)
+
 * ``sqlite3.OptimizedUnicode`` has been undocumented and obsolete since Python
  3.3, when it was made an alias to :class:`str`. It is now deprecated,
  scheduled for removal in Python 3.12.

Lib/importlib/_abc.py

@@ -1,6 +1,7 @@
 """Subset of importlib.abc used to reduce importlib.util imports."""
 from . import _bootstrap
 import abc
+import warnings
 
 
 class Loader(metaclass=abc.ABCMeta):
@@ -47,5 +48,7 @@ def module_repr(self, module):
  This method is deprecated.
 
  """
+ warnings.warn("importlib.abc.Loader.module_repr() is deprecated and "
+ "slated for removal in Python 3.12", DeprecationWarning)
  # The exception will cause ModuleType.__repr__ to ignore this method.
  raise NotImplementedError

Lib/importlib/_bootstrap.py

@@ -302,8 +302,6 @@ def _module_repr(module):
  except Exception:
  pass
  # Fall through to a catch-all which always succeeds.
- # We could use module.__class__.__name__ instead of 'module' in the
- # various repr permutations.
  try:
  name = module.__name__
  except AttributeError:
@@ -741,6 +739,8 @@ def module_repr(module):
  The method is deprecated. The import machinery does the job itself.
 
  """
+ _warnings.warn("BuiltinImporter.module_repr() is deprecated and "
+ "slated for removal in Python 3.12", DeprecationWarning)
  return f'<module {module.__name__!r} ({BuiltinImporter._ORIGIN})>'
 
  @classmethod
@@ -816,6 +816,8 @@ def module_repr(m):
  The method is deprecated. The import machinery does the job itself.
 
  """
+ _warnings.warn("FrozenImporter.module_repr() is deprecated and "
+ "slated for removal in Python 3.12", DeprecationWarning)
  return '<module {!r} ({})>'.format(m.__name__, FrozenImporter._ORIGIN)
 
  @classmethod

Lib/importlib/_bootstrap_external.py

@@ -1230,6 +1230,8 @@ def module_repr(module):
  The method is deprecated. The import machinery does the job itself.
 
  """
+ _warnings.warn("_NamespaceLoader.module_repr() is deprecated and "
+ "slated for removal in Python 3.12", DeprecationWarning)
  return '<module {!r} (namespace)>'.format(module.__name__)
 
  def is_package(self, fullname):

Lib/test/test_importlib/test_abc.py

@@ -220,8 +220,10 @@ def test_load_module(self):
 
  def test_module_repr(self):
  mod = types.ModuleType('blah')
- with self.assertRaises(NotImplementedError):
- self.ins.module_repr(mod)
+ with warnings.catch_warnings():
+ warnings.simplefilter("ignore")
+ with self.assertRaises(NotImplementedError):
+ self.ins.module_repr(mod)
  original_repr = repr(mod)
  mod.__loader__ = self.ins
  # Should still return a proper repr.

Lib/test/test_importlib/test_namespace_pkgs.py

@@ -3,6 +3,7 @@
 import os
 import sys
 import unittest
+import warnings
 
 from test.test_importlib import util
 
@@ -82,8 +83,10 @@ def test_cant_import_other(self):
 
  def test_module_repr(self):
  import foo.one
- self.assertEqual(foo.__spec__.loader.module_repr(foo),
- "<module 'foo' (namespace)>")
+ with warnings.catch_warnings():
+ warnings.simplefilter("ignore")
+ self.assertEqual(foo.__spec__.loader.module_repr(foo),
+ "<module 'foo' (namespace)>")
 
 
 class DynamicPathNamespacePackage(NamespacePackageTest):

Lib/test/test_importlib/test_windows.py

@@ -7,7 +7,6 @@
 import unittest
 from test import support
 from test.support import import_helper
-from distutils.util import get_platform
 from contextlib import contextmanager
 from .util import temp_module
 
@@ -18,6 +17,25 @@
  EnumKey, CloseKey, DeleteKey, OpenKey
 )
 
+def get_platform():
+ # Port of distutils.util.get_platform().
+ TARGET_TO_PLAT = {
+ 'x86' : 'win32',
+ 'x64' : 'win-amd64',
+ 'arm' : 'win-arm32',
+ }
+ if ('VSCMD_ARG_TGT_ARCH' in os.environ and
+ os.environ['VSCMD_ARG_TGT_ARCH'] in TARGET_TO_PLAT):
+ return TARGET_TO_PLAT[os.environ['VSCMD_ARG_TGT_ARCH']]
+ elif 'amd64' in sys.version.lower():
+ return 'win-amd64'
+ elif '(arm)' in sys.version.lower():
+ return 'win-arm32'
+ elif '(arm64)' in sys.version.lower():
+ return 'win-arm64'
+ else:
+ return sys.platform
+
 def delete_registry_tree(root, subkey):
  try:
  hkey = OpenKey(root, subkey, access=KEY_ALL_ACCESS)
@@ -101,7 +119,7 @@ def test_tagged_suffix(self):
 
  self.assertIn(expected_tag, suffixes)
 
- # Ensure the tags are in the correct order
+ # Ensure the tags are in the correct order.
  tagged_i = suffixes.index(expected_tag)
  self.assertLess(tagged_i, untagged_i)
 

Misc/NEWS.d/next/Library/2021-03-25-08-44-26.bpo-42136.rRY9e1.rst

@@ -0,0 +1,2 @@
+Deprecate all module_repr() methods found in importlib as their use is being
+phased out by Python 3.12.