pre-commit · asottile · Apr 21, 2026 · Apr 21, 2026
diff --git a/pre_commit/commands/hook_impl.py b/pre_commit/commands/hook_impl.py
@@ -16,7 +16,7 @@

 def _run_legacy(
        hook_type: str,
-        hook_dir: str,
+        hook_dir: str | None,
        args: Sequence[str],
 ) -> tuple[int, bytes]:
    if os.environ.get('PRE_COMMIT_RUNNING_LEGACY'):
@@ -33,6 +33,9 @@ def _run_legacy(
    else:
        stdin = b''

+    if hook_dir is None:  # git 2.54+ hooks
+        return 0, stdin
+
    # not running in legacy mode
    legacy_hook = os.path.join(hook_dir, f'{hook_type}.legacy')
    if not os.access(legacy_hook, os.X_OK):
@@ -259,7 +262,7 @@ def hook_impl(
        config: str,
        color: bool,
        hook_type: str,
-        hook_dir: str,
+        hook_dir: str | None,
        skip_on_missing_config: bool,
        args: Sequence[str],
 ) -> int:

diff --git a/tests/commands/hook_impl_test.py b/tests/commands/hook_impl_test.py
@@ -63,6 +63,11 @@ def test_run_legacy_does_not_exist(tmpdir):
    assert (retv, stdin) == (0, b'')


+def test_run_legacy_git_2_54():
+    retv, stdin = hook_impl._run_legacy('pre-commit', None, ())
+    assert (retv, stdin) == (0, b'')
+
+
 def test_run_legacy_executes_legacy_script(tmpdir, capfd):
    hook = tmpdir.join('pre-commit.legacy')
    hook.write('#!/usr/bin/env bash\necho hi "$@"\nexit 1\n')