gitpython-developers · Byron · Aug 28, 2026 · Aug 28, 2026
diff --git a/git/util.py b/git/util.py
@@ -80,6 +80,7 @@
     Sequence,
     Tuple,
     TYPE_CHECKING,
+    Type,
     TypeVar,
     Union,
     cast,
@@ -108,6 +109,7 @@
 
 T_IterableObj = TypeVar("T_IterableObj", bound=Union["IterableObj", "Has_id_attribute"], covariant=True)
 # So IterableList[Head] is subtype of IterableList[IterableObj].
+T_Actor = TypeVar("T_Actor", bound="Actor")
 
 _logger = logging.getLogger(__name__)
 
@@ -853,11 +855,27 @@ 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 Actor(name, email) when the fields are already separate.",
+            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."""
 
+    name_email_regex = _DeprecatedActorNameEmailRegex()
+
     # ENVIRONMENT VARIABLES
     # These are read when creating new commits.
     env_author_name = "GIT_AUTHOR_NAME"
@@ -891,7 +909,7 @@ def __repr__(self) -> str:
         return '<git.Actor "%s <%s>">' % (self.name, self.email)
 
     @classmethod
-    def _from_string(cls, string: str) -> "Actor":
+    def from_string(cls: Type[T_Actor], string: str) -> T_Actor:
         """Create an :class:`Actor` from a string.
 
         :param string:
@@ -906,10 +924,12 @@ def _from_string(cls, string: str) -> "Actor":
         left_bracket = line.find("<")
         right_bracket = line.find(">", left_bracket + 1)
         if left_bracket >= 0 and right_bracket >= 0:
-            return Actor(line[:left_bracket].rstrip(), line[left_bracket + 1 : right_bracket])
+            return cls(line[:left_bracket].rstrip(), line[left_bracket + 1 : right_bracket])
 
         # Assume the best and use the whole string as name.
-        return Actor(string, None)
+        return cls(string, None)
+
+    _from_string = from_string
 
     @classmethod
     def _main_actor(

diff --git a/test/test_actor.py b/test/test_actor.py
@@ -3,14 +3,15 @@
 # This module is part of GitPython and is released under the
 # 3-Clause BSD License: https://opensource.org/license/bsd-3-clause/
 
-from git import Actor
+from unittest import mock
 
+from git import Actor
 from test.lib import TestBase
 
 
 class TestActor(TestBase):
     def test_from_string_should_separate_name_and_email(self):
-        a = Actor._from_string("Michael Trier <mtrier@example.com>")
+        a = Actor.from_string("Michael Trier <mtrier@example.com>")
         self.assertEqual("Michael Trier", a.name)
         self.assertEqual("mtrier@example.com", a.email)
 
@@ -23,18 +24,34 @@ def test_from_string_should_separate_name_and_email(self):
         assert len(m) == 1
 
     def test_from_string_should_handle_just_name(self):
-        a = Actor._from_string("Michael Trier")
+        a = Actor.from_string("Michael Trier")
         self.assertEqual("Michael Trier", a.name)
         self.assertEqual(None, a.email)
 
+    def test_from_string_constructs_subclass(self):
+        class DerivedActor(Actor):
+            pass
+
+        self.assertIsInstance(DerivedActor.from_string("name <email>"), DerivedActor)
+
     def test_from_string_handles_unterminated_email_without_regex_backtracking(self):
         value = "A" * 20_000 + " <unterminated"
-        actor = Actor._from_string(value)
-        self.assertNotIn("name_email_regex", vars(Actor))
+        with mock.patch.object(Actor, "name_email_regex", None):
+            actor = Actor.from_string(value)
         self.assertEqual(actor, Actor(value, None))
 
+    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("Actor(name, email)", message)
+        assert match is not None
+        self.assertEqual(match.groups(), ("Michael Trier", "mtrier@example.com"))
+
     def test_from_string_does_not_parse_across_lines(self):
-        self.assertEqual(Actor._from_string("x <a>\n y <b>"), Actor("x", "a"))
+        self.assertEqual(Actor.from_string("x <a>\n y <b>"), Actor("x", "a"))
 
     def test_from_string_uses_git_delimiters(self):
         for value, expected in (
@@ -45,12 +62,12 @@ def test_from_string_uses_git_delimiters(self):
             ("Name <email", Actor("Name <email", None)),
             ("Name email>", Actor("Name email>", None)),
         ):
-            self.assertEqual(Actor._from_string(value), expected)
+            self.assertEqual(Actor.from_string(value), expected)
 
     def test_should_display_representation(self):
-        a = Actor._from_string("Michael Trier <mtrier@example.com>")
+        a = Actor.from_string("Michael Trier <mtrier@example.com>")
         self.assertEqual('<git.Actor "Michael Trier <mtrier@example.com>">', repr(a))
 
     def test_str_should_alias_name(self):
-        a = Actor._from_string("Michael Trier <mtrier@example.com>")
+        a = Actor.from_string("Michael Trier <mtrier@example.com>")
         self.assertEqual(a.name, str(a))