bpo-39595: Improve zipfile.Path performance (#18406)

* Improve zipfile.Path performance on zipfiles with a large number of entries.

* 📜🤖 Added by blurb_it.

* Add bpo to blurb

* Sync with importlib_metadata 1.5 (6fe70ca)

* Update blurb.

* Remove compatibility code

* Add stubs module, omitted from earlier commit

Co-authored-by: blurb-it[bot] <43283697+blurb-it[bot]@users.noreply.github.com>

1 files changed, 32 insertions, 0 deletions

diff --git a/Lib/test/test_importlib/test_main.py b/Lib/test/test_importlib/test_main.py
index c5f1dbb..42a7999 100644
--- a/Lib/test/test_importlib/test_main.py
+++ b/Lib/test/test_importlib/test_main.py
@@ -7,6 +7,11 @@ import textwrap
 import unittest
 import importlib.metadata
 
+try:
+    import pyfakefs.fake_filesystem_unittest as ffs
+except ImportError:
+    from .stubs import fake_filesystem_unittest as ffs
+
 from . import fixtures
 from importlib.metadata import (
     Distribution, EntryPoint,
@@ -185,6 +190,33 @@ class DirectoryTest(fixtures.OnSysPath, fixtures.SiteDir, unittest.TestCase):
                 version('foo')
 
 
+class MissingSysPath(fixtures.OnSysPath, unittest.TestCase):
+    site_dir = '/does-not-exist'
+
+    def test_discovery(self):
+        """
+        Discovering distributions should succeed even if
+        there is an invalid path on sys.path.
+        """
+        importlib.metadata.distributions()
+
+
+class InaccessibleSysPath(fixtures.OnSysPath, ffs.TestCase):
+    site_dir = '/access-denied'
+
+    def setUp(self):
+        super(InaccessibleSysPath, self).setUp()
+        self.setUpPyfakefs()
+        self.fs.create_dir(self.site_dir, perm_bits=000)
+
+    def test_discovery(self):
+        """
+        Discovering distributions should succeed even if
+        there is an invalid path on sys.path.
+        """
+        list(importlib.metadata.distributions())
+
+
 class TestEntryPoints(unittest.TestCase):
     def __init__(self, *args):
         super(TestEntryPoints, self).__init__(*args)