diff --git a/.pre-commit-config.yaml b/.pre-commit-config.yaml
index 3c38354437e..2f1bae939aa 100644
--- a/.pre-commit-config.yaml
+++ b/.pre-commit-config.yaml
@@ -39,7 +39,7 @@ repos:
         exclude: ^src/blib2to3/
 
   - repo: https://github.com/pre-commit/mirrors-mypy
-    rev: v1.13.0
+    rev: v1.14.1
     hooks:
       - id: mypy
         exclude: ^(docs/conf.py|scripts/generate_schema.py)$
diff --git a/tests/test_black.py b/tests/test_black.py
index 84061f10cdf..98d8ff886d7 100644
--- a/tests/test_black.py
+++ b/tests/test_black.py
@@ -1355,8 +1355,10 @@ def test_reformat_one_with_stdin_empty(self) -> None:
 
         def _new_wrapper(
             output: io.StringIO, io_TextIOWrapper: type[io.TextIOWrapper]
-        ) -> Callable[[Any, Any], io.TextIOWrapper]:
-            def get_output(*args: Any, **kwargs: Any) -> io.TextIOWrapper:
+        ) -> Callable[[Any, Any], Union[io.StringIO, io.TextIOWrapper]]:
+            def get_output(
+                *args: Any, **kwargs: Any
+            ) -> Union[io.StringIO, io.TextIOWrapper]:
                 if args == (sys.stdout.buffer,):
                     # It's `format_stdin_to_stdout()` calling `io.TextIOWrapper()`,
                     # return our mock object.