GH-128520: pathlib ABCs: allow tests to be run externally (#131315)

Adjust the tests for the `pathlib.types` module so that they can be run
against the `pathlib-abc` PyPI package, which is a backport of the module
for older Python versions.

Specifically, we add a `.support.is_pypi` switch that is false in the
stdlib and true in the pathlib-abc package. This controls which package
we import, and whether or not we run tests against `PurePath` and `Path`.

For compatibility with older Python versions, we stop using
`zipfile.ZipFile.mkdir()` and `zipfile.ZipInfo._for_archive()`.

1 files changed, 9 insertions, 7 deletions

diff --git a/Lib/test/test_pathlib/test_join_posix.py b/Lib/test/test_pathlib/test_join_posix.py
index 7f657c2565d..d24fb1087c9 100644
--- a/Lib/test/test_pathlib/test_join_posix.py
+++ b/Lib/test/test_pathlib/test_join_posix.py
@@ -5,8 +5,8 @@ Tests for Posix-flavoured pathlib.types._JoinablePath
 import os
 import unittest
 
-from pathlib import PurePosixPath, PosixPath
-from test.test_pathlib.support.lexical_path import LexicalPosixPath
+from .support import is_pypi
+from .support.lexical_path import LexicalPosixPath
 
 
 class JoinTestBase:
@@ -36,13 +36,15 @@ class LexicalPosixPathJoinTest(JoinTestBase, unittest.TestCase):
     cls = LexicalPosixPath
 
 
-class PurePosixPathJoinTest(JoinTestBase, unittest.TestCase):
-    cls = PurePosixPath
+if not is_pypi:
+    from pathlib import PurePosixPath, PosixPath
 
+    class PurePosixPathJoinTest(JoinTestBase, unittest.TestCase):
+        cls = PurePosixPath
 
-if os.name != 'nt':
-    class PosixPathJoinTest(JoinTestBase, unittest.TestCase):
-        cls = PosixPath
+    if os.name != 'nt':
+        class PosixPathJoinTest(JoinTestBase, unittest.TestCase):
+            cls = PosixPath
 
 
 if __name__ == "__main__":