Added type hints

Tests/test_file_jpeg.py

@@ -701,7 +701,7 @@ class TestFileJpeg:
     def test_save_cjpeg(self, tmp_path: Path) -> None:
         with Image.open(TEST_FILE) as img:
             tempfile = str(tmp_path / "temp.jpg")
-            JpegImagePlugin._save_cjpeg(img, 0, tempfile)
+            JpegImagePlugin._save_cjpeg(img, BytesIO(), tempfile)
             # Default save quality is 75%, so a tiny bit of difference is alright
             assert_image_similar_tofile(img, tempfile, 17)
 

Tests/test_file_jpeg2k.py

@@ -460,7 +460,7 @@ def test_plt_marker() -> None:
         out.seek(length - 2, os.SEEK_CUR)
 
 
-def test_9bit():
+def test_9bit() -> None:
     with Image.open("Tests/images/9bit.j2k") as im:
         assert im.mode == "I;16"
         assert im.size == (128, 128)

Tests/test_image.py

@@ -152,7 +152,7 @@ class TestImage:
 
     def test_stringio(self) -> None:
         with pytest.raises(ValueError):
-            with Image.open(io.StringIO()):
+            with Image.open(io.StringIO()):  # type: ignore[arg-type]
                 pass
 
     def test_pathlib(self, tmp_path: Path) -> None:

Tests/test_image_putdata.py

@@ -113,13 +113,13 @@ def test_array_F() -> None:
 def test_not_flattened() -> None:
     im = Image.new("L", (1, 1))
     with pytest.raises(TypeError):
-        im.putdata([[0]])
+        im.putdata([[0]])  # type: ignore[list-item]
     with pytest.raises(TypeError):
-        im.putdata([[0]], 2)
+        im.putdata([[0]], 2)  # type: ignore[list-item]
 
     with pytest.raises(TypeError):
         im = Image.new("I", (1, 1))
-        im.putdata([[0]])
+        im.putdata([[0]])  # type: ignore[list-item]
     with pytest.raises(TypeError):
         im = Image.new("F", (1, 1))
-        im.putdata([[0]])
+        im.putdata([[0]])  # type: ignore[list-item]

Tests/test_numpy.py

@@ -1,6 +1,7 @@
 from __future__ import annotations
 
 import warnings
+from typing import TYPE_CHECKING, Any
 
 import pytest
 
@@ -8,13 +9,19 @@ from PIL import Image
 
 from .helper import assert_deep_equal, assert_image, hopper, skip_unless_feature
 
-numpy = pytest.importorskip("numpy", reason="NumPy not installed")
+if TYPE_CHECKING:
+    import numpy
+    import numpy.typing
+else:
+    numpy = pytest.importorskip("numpy", reason="NumPy not installed")
 
 TEST_IMAGE_SIZE = (10, 10)
 
 
 def test_numpy_to_image() -> None:
-    def to_image(dtype, bands: int = 1, boolean: int = 0) -> Image.Image:
+    def to_image(
+        dtype: numpy.typing.DTypeLike, bands: int = 1, boolean: int = 0
+    ) -> Image.Image:
         if bands == 1:
             if boolean:
                 data = [0, 255] * 50
@@ -99,14 +106,16 @@ def test_1d_array() -> None:
     assert_image(Image.fromarray(a), "L", (1, 5))
 
 
-def _test_img_equals_nparray(img: Image.Image, np) -> None:
+def _test_img_equals_nparray(
-    assert len(np.shape) >= 2
+    img: Image.Image, np_img: numpy.typing.NDArray[Any]
-    np_size = np.shape[1], np.shape[0]
+) -> None:
+    assert len(np_img.shape) >= 2
+    np_size = np_img.shape[1], np_img.shape[0]
     assert img.size == np_size
     px = img.load()
     for x in range(0, img.size[0], int(img.size[0] / 10)):
         for y in range(0, img.size[1], int(img.size[1] / 10)):
-            assert_deep_equal(px[x, y], np[y, x])
+            assert_deep_equal(px[x, y], np_img[y, x])
 
 
 def test_16bit() -> None:
@@ -157,7 +166,7 @@ def test_save_tiff_uint16() -> None:
         ("HSV", numpy.uint8),
     ),
 )
-def test_to_array(mode: str, dtype) -> None:
+def test_to_array(mode: str, dtype: numpy.typing.DTypeLike) -> None:
     img = hopper(mode)
 
     # Resize to non-square
@@ -207,7 +216,7 @@ def test_putdata() -> None:
         numpy.float64,
     ),
 )
-def test_roundtrip_eye(dtype) -> None:
+def test_roundtrip_eye(dtype: numpy.typing.DTypeLike) -> None:
     arr = numpy.eye(10, dtype=dtype)
     numpy.testing.assert_array_equal(arr, numpy.array(Image.fromarray(arr)))
 

Tests/test_shell_injection.py

@@ -1,8 +1,9 @@
 from __future__ import annotations
 
 import shutil
+from io import BytesIO
 from pathlib import Path
-from typing import Callable
+from typing import IO, Callable
 
 import pytest
 
@@ -22,11 +23,11 @@ class TestShellInjection:
         self,
         tmp_path: Path,
         src_img: Image.Image,
-        save_func: Callable[[Image.Image, int, str], None],
+        save_func: Callable[[Image.Image, IO[bytes], str | bytes], None],
     ) -> None:
         for filename in test_filenames:
             dest_file = str(tmp_path / filename)
-            save_func(src_img, 0, dest_file)
+            save_func(src_img, BytesIO(), dest_file)
             # If file can't be opened, shell injection probably occurred
             with Image.open(dest_file) as im:
                 im.load()