From d9eafb746f4a8b4383a93acc29beada1e343e694 Mon Sep 17 00:00:00 2001
From: "Jason R. Coombs" <jaraco@jaraco.com>
Date: Tue, 18 Apr 2023 08:56:29 -0400
Subject: [PATCH] Apply changes from importlib_metadata 6.5.0

---
 Lib/importlib/metadata/__init__.py            | 21 ++++++++++++++++++-
 Lib/test/test_importlib/_context.py           | 13 ++++++++++++
 Lib/test/test_importlib/test_main.py          | 13 ++++++++++++
 ...-04-16-19-48-21.gh-issue-103584.3mBTuM.rst | 10 ++++-----
 4 files changed, 51 insertions(+), 6 deletions(-)
 create mode 100644 Lib/test/test_importlib/_context.py

diff --git a/Lib/importlib/metadata/__init__.py b/Lib/importlib/metadata/__init__.py
index 54194a69a1a6ac..b8eb19d05dccae 100644
--- a/Lib/importlib/metadata/__init__.py
+++ b/Lib/importlib/metadata/__init__.py
@@ -343,7 +343,26 @@ def __repr__(self):
         return f'<FileHash mode: {self.mode} value: {self.value}>'
 
 
-class Distribution(metaclass=abc.ABCMeta):
+class DeprecatedNonAbstract:
+    def __new__(cls, *args, **kwargs):
+        all_names = {
+            name for subclass in inspect.getmro(cls) for name in vars(subclass)
+        }
+        abstract = {
+            name
+            for name in all_names
+            if getattr(getattr(cls, name), '__isabstractmethod__', False)
+        }
+        if abstract:
+            warnings.warn(
+                f"Unimplemented abstract methods {abstract}",
+                DeprecationWarning,
+                stacklevel=2,
+            )
+        return super().__new__(cls)
+
+
+class Distribution(DeprecatedNonAbstract):
     """A Python distribution package."""
 
     @abc.abstractmethod
diff --git a/Lib/test/test_importlib/_context.py b/Lib/test/test_importlib/_context.py
new file mode 100644
index 00000000000000..8a53eb55d1503b
--- /dev/null
+++ b/Lib/test/test_importlib/_context.py
@@ -0,0 +1,13 @@
+import contextlib
+
+
+# from jaraco.context 4.3
+class suppress(contextlib.suppress, contextlib.ContextDecorator):
+    """
+    A version of contextlib.suppress with decorator support.
+
+    >>> @suppress(KeyError)
+    ... def key_error():
+    ...     {}['']
+    >>> key_error()
+    """
diff --git a/Lib/test/test_importlib/test_main.py b/Lib/test/test_importlib/test_main.py
index 5f6a0d08c16f33..46cd2b696d4cc8 100644
--- a/Lib/test/test_importlib/test_main.py
+++ b/Lib/test/test_importlib/test_main.py
@@ -1,7 +1,9 @@
 import re
 import pickle
 import unittest
+import warnings
 import importlib.metadata
+import contextlib
 import itertools
 
 try:
@@ -10,6 +12,7 @@
     from .stubs import fake_filesystem_unittest as ffs
 
 from . import fixtures
+from ._context import suppress
 from importlib.metadata import (
     Distribution,
     EntryPoint,
@@ -23,6 +26,13 @@
 )
 
 
+@contextlib.contextmanager
+def suppress_known_deprecation():
+    with warnings.catch_warnings(record=True) as ctx:
+        warnings.simplefilter('default', category=DeprecationWarning)
+        yield ctx
+
+
 class BasicTests(fixtures.DistInfoPkg, unittest.TestCase):
     version_pattern = r'\d+\.\d+(\.\d)?'
 
@@ -47,6 +57,9 @@ def test_package_not_found_mentions_metadata(self):
 
         assert "metadata" in str(ctx.exception)
 
+    # expected to fail until ABC is enforced
+    @suppress(AssertionError)
+    @suppress_known_deprecation()
     def test_abc_enforced(self):
         with self.assertRaises(TypeError):
             type('DistributionSubclass', (Distribution,), {})()
diff --git a/Misc/NEWS.d/next/Library/2023-04-16-19-48-21.gh-issue-103584.3mBTuM.rst b/Misc/NEWS.d/next/Library/2023-04-16-19-48-21.gh-issue-103584.3mBTuM.rst
index d0acb7931359bc..6d7c93ade9cd94 100644
--- a/Misc/NEWS.d/next/Library/2023-04-16-19-48-21.gh-issue-103584.3mBTuM.rst
+++ b/Misc/NEWS.d/next/Library/2023-04-16-19-48-21.gh-issue-103584.3mBTuM.rst
@@ -1,12 +1,12 @@
 Updated ``importlib.metadata`` with changes from ``importlib_metadata`` 5.2
-through 6.4.1, including: Support ``installed-files.txt`` for
+through 6.5.0, including: Support ``installed-files.txt`` for
 ``Distribution.files`` when present. ``PackageMetadata`` now stipulates an
 additional ``get`` method allowing for easy querying of metadata keys that
 may not be present. ``packages_distributions`` now honors packages and
 modules with Python modules that not ``.py`` sources (e.g. ``.pyc``,
 ``.so``). Expand protocol for ``PackageMetadata.get_all`` to match the
 upstream implementation of ``email.message.Message.get_all`` in
-python/typeshed#9620. Declared ``Distribution`` as an abstract class,
-enforcing definition of abstract methods in instantiated subclasses.
-Deprecated expectation that ``PackageMetadata.__getitem__`` will return
-``None`` for missing keys. In the future, it will raise a ``KeyError``.
+python/typeshed#9620. Deprecated use of ``Distribution`` without defining
+abstract methods. Deprecated expectation that
+``PackageMetadata.__getitem__`` will return ``None`` for missing keys. In
+the future, it will raise a ``KeyError``.