Added type hints

Tests/test_file_gbr.py

@@ -33,7 +33,7 @@ def test_multiple_load_operations() -> None:
         assert_image_equal_tofile(im, "Tests/images/gbr.png")
 
 
-def create_gbr_image(info: dict[str, int] = {}, magic_number=b"") -> BytesIO:
+def create_gbr_image(info: dict[str, int] = {}, magic_number: bytes = b"") -> BytesIO:
     return BytesIO(
         b"".join(
             _binary.o32be(i)

Tests/test_file_iptc.py

@@ -12,7 +12,7 @@ TEST_FILE = "Tests/images/iptc.jpg"
 
 
 def create_iptc_image(info: dict[str, int] = {}) -> BytesIO:
-    def field(tag, value):
+    def field(tag: tuple[int, int], value: bytes) -> bytes:
         return bytes((0x1C,) + tag + (0, len(value))) + value
 
     data = field((3, 60), bytes((info.get("layers", 1), info.get("component", 0))))

src/PIL/ImageText.py

@@ -88,7 +88,7 @@ class Text:
         else:
             return "L"
 
-    def get_length(self):
+    def get_length(self) -> float:
         """
         Returns length (in pixels with 1/64 precision) of text.
 
@@ -130,8 +130,7 @@ class Text:
 
         :return: Either width for horizontal text, or height for vertical text.
         """
-        split_character = "\n" if isinstance(self.text, str) else b"\n"
-        if split_character in self.text:
+        if "\n" in self.text if isinstance(self.text, str) else b"\n" in self.text:
             msg = "can't measure length of multiline text"
             raise ValueError(msg)
         return self.font.getlength(