[3.12] gh-93205: When rotating logs with no namer specified, match whole extension (GH-93224) (GH-115784)

(cherry picked from commit 113687a838)

Co-authored-by: Gabriele Catania <gabriele.ctn@gmail.com>

Lib/test/test_logging.py

@@ -6138,6 +6138,43 @@ class TimedRotatingFileHandlerTest(BaseFileTest):
                     self.assertTrue(fn.startswith(prefix + '.') and
                                     fn[len(prefix) + 2].isdigit())
 
+    def test_compute_files_to_delete_same_filename_different_extensions(self):
+        # See GH-93205 for background
+        wd = pathlib.Path(tempfile.mkdtemp(prefix='test_logging_'))
+        self.addCleanup(shutil.rmtree, wd)
+        times = []
+        dt = datetime.datetime.now()
+        n_files = 10
+        for _ in range(n_files):
+            times.append(dt.strftime('%Y-%m-%d_%H-%M-%S'))
+            dt += datetime.timedelta(seconds=5)
+        prefixes = ('a.log', 'a.log.b')
+        files = []
+        rotators = []
+        for i, prefix in enumerate(prefixes):
+            backupCount = i+1
+            rotator = logging.handlers.TimedRotatingFileHandler(wd / prefix, when='s',
+                                                                interval=5,
+                                                                backupCount=backupCount,
+                                                                delay=True)
+            rotators.append(rotator)
+            for t in times:
+                files.append('%s.%s' % (prefix, t))
+        # Create empty files
+        for f in files:
+            (wd / f).touch()
+        # Now the checks that only the correct files are offered up for deletion
+        for i, prefix in enumerate(prefixes):
+            backupCount = i+1
+            rotator = rotators[i]
+            candidates = rotator.getFilesToDelete()
+            self.assertEqual(len(candidates), n_files - backupCount)
+            matcher = re.compile(r"^\d{4}-\d{2}-\d{2}_\d{2}-\d{2}-\d{2}(\.\w+)?$")
+            for c in candidates:
+                d, fn = os.path.split(c)
+                self.assertTrue(fn.startswith(prefix))
+                suffix = fn[(len(prefix)+1):]
+                self.assertRegex(suffix, matcher)
 
 def secs(**kw):
     return datetime.timedelta(**kw) // datetime.timedelta(seconds=1)