From: Barney Gale <barney.gale@gmail.com>
Date: Tue, 30 Jan 2024 14:25:16 +0000 (+0000)
Subject: GH-114610: Fix `pathlib._abc.PurePathBase.with_suffix('.ext')` handling of stems... 
X-Git-Tag: v3.13.0a4~258
X-Git-Url: http://git.ipfire.org/gitweb.cgi?a=commitdiff_plain;h=809eed48058ea7391df57ead09dff53bcc5d81e9;p=thirdparty%2FPython%2Fcpython.git

GH-114610: Fix `pathlib._abc.PurePathBase.with_suffix('.ext')` handling of stems (#114613)

Raise `ValueError` if `with_suffix('.ext')` is called on a path without a
stem. Paths may only have a non-empty suffix if they also have a non-empty
stem.

ABC-only bugfix; no effect on public classes.
---

diff --git a/Lib/pathlib/_abc.py b/Lib/pathlib/_abc.py
index ad5684829ebc..580d631cbf3b 100644
--- a/Lib/pathlib/_abc.py
+++ b/Lib/pathlib/_abc.py
@@ -299,10 +299,13 @@ class PurePathBase:
         has no suffix, add given suffix.  If the given suffix is an empty
         string, remove the suffix from the path.
         """
+        stem = self.stem
         if not suffix:
-            return self.with_name(self.stem)
+            return self.with_name(stem)
+        elif not stem:
+            raise ValueError(f"{self!r} has an empty name")
         elif suffix.startswith('.') and len(suffix) > 1:
-            return self.with_name(self.stem + suffix)
+            return self.with_name(stem + suffix)
         else:
             raise ValueError(f"Invalid suffix {suffix!r}")
 
diff --git a/Lib/test/test_pathlib/test_pathlib.py b/Lib/test/test_pathlib/test_pathlib.py
index 5ce3b605c58e..a8cc30ef0ab6 100644
--- a/Lib/test/test_pathlib/test_pathlib.py
+++ b/Lib/test/test_pathlib/test_pathlib.py
@@ -327,13 +327,6 @@ class PurePathTest(test_pathlib_abc.DummyPurePathTest):
         self.assertRaises(ValueError, P('a/b').with_stem, '')
         self.assertRaises(ValueError, P('a/b').with_stem, '.')
 
-    def test_with_suffix_empty(self):
-        # Path doesn't have a "filename" component.
-        P = self.cls
-        self.assertRaises(ValueError, P('').with_suffix, '.gz')
-        self.assertRaises(ValueError, P('.').with_suffix, '.gz')
-        self.assertRaises(ValueError, P('/').with_suffix, '.gz')
-
     def test_relative_to_several_args(self):
         P = self.cls
         p = P('a/b')
diff --git a/Lib/test/test_pathlib/test_pathlib_abc.py b/Lib/test/test_pathlib/test_pathlib_abc.py
index ab989cb5503f..18a612f6b81b 100644
--- a/Lib/test/test_pathlib/test_pathlib_abc.py
+++ b/Lib/test/test_pathlib/test_pathlib_abc.py
@@ -977,9 +977,8 @@ class DummyPurePathTest(unittest.TestCase):
     def test_with_suffix_empty(self):
         P = self.cls
         # Path doesn't have a "filename" component.
-        self.assertEqual(P('').with_suffix('.gz'), P('.gz'))
-        self.assertEqual(P('.').with_suffix('.gz'), P('..gz'))
-        self.assertEqual(P('/').with_suffix('.gz'), P('/.gz'))
+        self.assertRaises(ValueError, P('').with_suffix, '.gz')
+        self.assertRaises(ValueError, P('/').with_suffix, '.gz')
 
     def test_with_suffix_seps(self):
         P = self.cls