gitpython-developers
diff --git a/‎git/util.py‎
Lines changed: 15 additions & 3 deletions b/‎git/util.py‎
Lines changed: 15 additions & 3 deletions
diff --git a/‎test/test_actor.py‎
Lines changed: 7 additions & 2 deletions b/‎test/test_actor.py‎
Lines changed: 7 additions & 2 deletions
@@ -853,14 +853,26 @@ def update(self, *args: Any, **kwargs: Any) -> None:
         self._callable(*args, **kwargs)
 
 
+class _DeprecatedActorNameEmailRegex:
+    _pattern = re.compile(r"(.*) <(.*?)>")
+
+    def __get__(self, _instance: Any, _owner: Any) -> Pattern[str]:
+        warnings.warn(
+            "Actor.name_email_regex is deprecated and will be removed in GitPython 4.0.0 because searching long "
+            "malformed strings with it can take quadratic time. Use Actor._from_string() to parse actor identities, "
+            "or str.partition() and str.find() for custom validation.",
+            DeprecationWarning,
+            stacklevel=2,
+        )
+        return self._pattern
+
+
 class Actor:
     """Actors hold information about a person acting on the repository. They can be
     committers and authors or anything with a name and an email as mentioned in the git
     log entries."""
 
-    # Kept for compatibility only: searching long malformed strings with this regex can
-    # take quadratic time. ``_from_string`` deliberately uses delimiter scans instead.
-    name_email_regex = re.compile(r"(.*) <(.*?)>")
+    name_email_regex = _DeprecatedActorNameEmailRegex()
 
     # ENVIRONMENT VARIABLES
     # These are read when creating new commits.
 
@@ -35,8 +35,13 @@ def test_from_string_handles_unterminated_email_without_regex_backtracking(self)
             actor = Actor._from_string(value)
         self.assertEqual(actor, Actor(value, None))
 
-    def test_name_email_regex_is_available(self):
-        match = Actor.name_email_regex.match("Michael Trier <mtrier@example.com>")
+    def test_name_email_regex_is_available_but_deprecated(self):
+        with self.assertWarns(DeprecationWarning) as context:
+            match = Actor.name_email_regex.match("Michael Trier <mtrier@example.com>")
+
+        message = str(context.warning)
+        self.assertIn("Actor._from_string()", message)
+        self.assertIn("str.partition()", message)
         self.assertIsNotNone(match)
         self.assertEqual(match.groups(), ("Michael Trier", "mtrier@example.com"))