Merge branch 'main' into type-hints-replace-io.BytesIO

.coveragerc

@@ -10,6 +10,8 @@ exclude_also =
     if DEBUG:
     # Don't complain about compatibility code for missing optional dependencies
     except ImportError
+    if TYPE_CHECKING:
+    @abc.abstractmethod
     # Empty bodies in protocols or abstract methods
     ^\s*def [a-zA-Z0-9_]+\(.*\)(\s*->.*)?:\s*\.\.\.(\s*#.*)?$
     ^\s*\.\.\.(\s*#.*)?$

Tests/test_color_lut.py

@@ -15,7 +15,9 @@ except ImportError:
 
 
 class TestColorLut3DCoreAPI:
-    def generate_identity_table(self, channels, size):
+    def generate_identity_table(
+        self, channels: int, size: int | tuple[int, int, int]
+    ) -> tuple[int, int, int, int, list[float]]:
         if isinstance(size, tuple):
             size_1d, size_2d, size_3d = size
         else:

Tests/test_file_eps.py

@@ -84,7 +84,7 @@ simple_eps_file_with_long_binary_data = (
     ("filename", "size"), ((FILE1, (460, 352)), (FILE2, (360, 252)))
 )
 @pytest.mark.parametrize("scale", (1, 2))
-def test_sanity(filename, size, scale) -> None:
+def test_sanity(filename: str, size: tuple[int, int], scale: int) -> None:
     expected_size = tuple(s * scale for s in size)
     with Image.open(filename) as image:
         image.load(scale=scale)
@@ -129,28 +129,28 @@ def test_binary_header_only() -> None:
 
 
 @pytest.mark.parametrize("prefix", (b"", simple_binary_header))
-def test_missing_version_comment(prefix) -> None:
+def test_missing_version_comment(prefix: bytes) -> None:
     data = io.BytesIO(prefix + b"\n".join(simple_eps_file_without_version))
     with pytest.raises(SyntaxError):
         EpsImagePlugin.EpsImageFile(data)
 
 
 @pytest.mark.parametrize("prefix", (b"", simple_binary_header))
-def test_missing_boundingbox_comment(prefix) -> None:
+def test_missing_boundingbox_comment(prefix: bytes) -> None:
     data = io.BytesIO(prefix + b"\n".join(simple_eps_file_without_boundingbox))
     with pytest.raises(SyntaxError, match='EPS header missing "%%BoundingBox" comment'):
         EpsImagePlugin.EpsImageFile(data)
 
 
 @pytest.mark.parametrize("prefix", (b"", simple_binary_header))
-def test_invalid_boundingbox_comment(prefix) -> None:
+def test_invalid_boundingbox_comment(prefix: bytes) -> None:
     data = io.BytesIO(prefix + b"\n".join(simple_eps_file_with_invalid_boundingbox))
     with pytest.raises(OSError, match="cannot determine EPS bounding box"):
         EpsImagePlugin.EpsImageFile(data)
 
 
 @pytest.mark.parametrize("prefix", (b"", simple_binary_header))
-def test_invalid_boundingbox_comment_valid_imagedata_comment(prefix) -> None:
+def test_invalid_boundingbox_comment_valid_imagedata_comment(prefix: bytes) -> None:
     data = io.BytesIO(
         prefix + b"\n".join(simple_eps_file_with_invalid_boundingbox_valid_imagedata)
     )
@@ -161,21 +161,21 @@ def test_invalid_boundingbox_comment_valid_imagedata_comment(prefix) -> None:
 
 
 @pytest.mark.parametrize("prefix", (b"", simple_binary_header))
-def test_ascii_comment_too_long(prefix) -> None:
+def test_ascii_comment_too_long(prefix: bytes) -> None:
     data = io.BytesIO(prefix + b"\n".join(simple_eps_file_with_long_ascii_comment))
     with pytest.raises(SyntaxError, match="not an EPS file"):
         EpsImagePlugin.EpsImageFile(data)
 
 
 @pytest.mark.parametrize("prefix", (b"", simple_binary_header))
-def test_long_binary_data(prefix) -> None:
+def test_long_binary_data(prefix: bytes) -> None:
     data = io.BytesIO(prefix + b"\n".join(simple_eps_file_with_long_binary_data))
     EpsImagePlugin.EpsImageFile(data)
 
 
 @pytest.mark.skipif(not HAS_GHOSTSCRIPT, reason="Ghostscript not available")
 @pytest.mark.parametrize("prefix", (b"", simple_binary_header))
-def test_load_long_binary_data(prefix) -> None:
+def test_load_long_binary_data(prefix: bytes) -> None:
     data = io.BytesIO(prefix + b"\n".join(simple_eps_file_with_long_binary_data))
     with Image.open(data) as img:
         img.load()
@@ -305,7 +305,7 @@ def test_render_scale2() -> None:
 
 @pytest.mark.skipif(not HAS_GHOSTSCRIPT, reason="Ghostscript not available")
 @pytest.mark.parametrize("filename", (FILE1, FILE2, "Tests/images/illu10_preview.eps"))
-def test_resize(filename) -> None:
+def test_resize(filename: str) -> None:
     with Image.open(filename) as im:
         new_size = (100, 100)
         im = im.resize(new_size)
@@ -314,7 +314,7 @@ def test_resize(filename) -> None:
 
 @pytest.mark.skipif(not HAS_GHOSTSCRIPT, reason="Ghostscript not available")
 @pytest.mark.parametrize("filename", (FILE1, FILE2))
-def test_thumbnail(filename) -> None:
+def test_thumbnail(filename: str) -> None:
     # Issue #619
     with Image.open(filename) as im:
         new_size = (100, 100)
@@ -335,7 +335,7 @@ def test_readline_psfile(tmp_path: Path) -> None:
     line_endings = ["\r\n", "\n", "\n\r", "\r"]
     strings = ["something", "else", "baz", "bif"]
 
-    def _test_readline(t, ending) -> None:
+    def _test_readline(t: EpsImagePlugin.PSFile, ending: str) -> None:
         ending = "Failure with line ending: %s" % (
             "".join("%s" % ord(s) for s in ending)
         )
@@ -344,13 +344,13 @@ def test_readline_psfile(tmp_path: Path) -> None:
         assert t.readline().strip("\r\n") == "baz", ending
         assert t.readline().strip("\r\n") == "bif", ending
 
-    def _test_readline_io_psfile(test_string, ending) -> None:
+    def _test_readline_io_psfile(test_string: str, ending: str) -> None:
         f = io.BytesIO(test_string.encode("latin-1"))
         with pytest.warns(DeprecationWarning):
             t = EpsImagePlugin.PSFile(f)
         _test_readline(t, ending)
 
-    def _test_readline_file_psfile(test_string, ending) -> None:
+    def _test_readline_file_psfile(test_string: str, ending: str) -> None:
         f = str(tmp_path / "temp.txt")
         with open(f, "wb") as w:
             w.write(test_string.encode("latin-1"))
@@ -376,7 +376,7 @@ def test_psfile_deprecation() -> None:
     "line_ending",
     (b"\r\n", b"\n", b"\n\r", b"\r"),
 )
-def test_readline(prefix, line_ending) -> None:
+def test_readline(prefix: bytes, line_ending: bytes) -> None:
     simple_file = prefix + line_ending.join(simple_eps_file_with_comments)
     data = io.BytesIO(simple_file)
     test_file = EpsImagePlugin.EpsImageFile(data)
@@ -394,7 +394,7 @@ def test_readline(prefix, line_ending) -> None:
         "Tests/images/illuCS6_preview.eps",
     ),
 )
-def test_open_eps(filename) -> None:
+def test_open_eps(filename: str) -> None:
     # https://github.com/python-pillow/Pillow/issues/1104
     with Image.open(filename) as img:
         assert img.mode == "RGB"
@@ -417,7 +417,7 @@ def test_emptyline() -> None:
     "test_file",
     ["Tests/images/timeout-d675703545fee17acab56e5fec644c19979175de.eps"],
 )
-def test_timeout(test_file) -> None:
+def test_timeout(test_file: str) -> None:
     with open(test_file, "rb") as f:
         with pytest.raises(Image.UnidentifiedImageError):
             with Image.open(f):

Tests/test_file_jpeg.py

@@ -5,6 +5,7 @@ import re
 import warnings
 from io import BytesIO
 from pathlib import Path
+from typing import Any
 
 import pytest
 
@@ -42,7 +43,7 @@ TEST_FILE = "Tests/images/hopper.jpg"
 
 @skip_unless_feature("jpg")
 class TestFileJpeg:
-    def roundtrip(self, im, **options):
+    def roundtrip(self, im: Image.Image, **options: Any) -> Image.Image:
         out = BytesIO()
         im.save(out, "JPEG", **options)
         test_bytes = out.tell()
@@ -51,7 +52,7 @@ class TestFileJpeg:
         im.bytes = test_bytes  # for testing only
         return im
 
-    def gen_random_image(self, size, mode: str = "RGB"):
+    def gen_random_image(self, size: tuple[int, int], mode: str = "RGB") -> Image.Image:
         """Generates a very hard to compress file
         :param size: tuple
         :param mode: optional image mode
@@ -71,7 +72,7 @@ class TestFileJpeg:
             assert im.get_format_mimetype() == "image/jpeg"
 
     @pytest.mark.parametrize("size", ((1, 0), (0, 1), (0, 0)))
-    def test_zero(self, size, tmp_path: Path) -> None:
+    def test_zero(self, size: tuple[int, int], tmp_path: Path) -> None:
         f = str(tmp_path / "temp.jpg")
         im = Image.new("RGB", size)
         with pytest.raises(ValueError):
@@ -108,13 +109,11 @@ class TestFileJpeg:
                     assert "comment" not in reloaded.info
 
             # Test that a comment argument overrides the default comment
-            for comment in ("Test comment text", b"Text comment text"):
+            for comment in ("Test comment text", b"Test comment text"):
                 out = BytesIO()
                 im.save(out, format="JPEG", comment=comment)
                 with Image.open(out) as reloaded:
-                    if not isinstance(comment, bytes):
+                    assert reloaded.info["comment"] == b"Test comment text"
-                        comment = comment.encode()
-                    assert reloaded.info["comment"] == comment
 
     def test_cmyk(self) -> None:
         # Test CMYK handling.  Thanks to Tim and Charlie for test data,
@@ -145,7 +144,7 @@ class TestFileJpeg:
             assert k > 0.9
 
     def test_rgb(self) -> None:
-        def getchannels(im):
+        def getchannels(im: Image.Image) -> tuple[int, int, int]:
             return tuple(v[0] for v in im.layer)
 
         im = hopper()
@@ -161,8 +160,8 @@ class TestFileJpeg:
         "test_image_path",
         [TEST_FILE, "Tests/images/pil_sample_cmyk.jpg"],
     )
-    def test_dpi(self, test_image_path) -> None:
+    def test_dpi(self, test_image_path: str) -> None:
-        def test(xdpi, ydpi=None):
+        def test(xdpi: int, ydpi: int | None = None):
             with Image.open(test_image_path) as im:
                 im = self.roundtrip(im, dpi=(xdpi, ydpi or xdpi))
             return im.info.get("dpi")
@@ -207,7 +206,7 @@ class TestFileJpeg:
             ImageFile.MAXBLOCK * 4 + 3,  # large block
         ),
     )
-    def test_icc_big(self, n) -> None:
+    def test_icc_big(self, n: int) -> None:
         # Make sure that the "extra" support handles large blocks
         # The ICC APP marker can store 65519 bytes per marker, so
         # using a 4-byte test code should allow us to detect out of
@@ -433,7 +432,7 @@ class TestFileJpeg:
         assert_image(im1, im2.mode, im2.size)
 
     def test_subsampling(self) -> None:
-        def getsampling(im):
+        def getsampling(im: Image.Image):
             layer = im.layer
             return layer[0][1:3] + layer[1][1:3] + layer[2][1:3]
 
@@ -530,7 +529,7 @@ class TestFileJpeg:
         pytest.mark.valgrind_known_error, "libjpeg_turbo", "2.0", reason="Known Failing"
     )
     def test_qtables(self, tmp_path: Path) -> None:
-        def _n_qtables_helper(n, test_file) -> None:
+        def _n_qtables_helper(n: int, test_file: str) -> None:
             with Image.open(test_file) as im:
                 f = str(tmp_path / "temp.jpg")
                 im.save(f, qtables=[[n] * 64] * n)
@@ -666,7 +665,7 @@ class TestFileJpeg:
         "blocks, rows, markers",
         ((0, 0, 0), (1, 0, 15), (3, 0, 5), (8, 0, 1), (0, 1, 3), (0, 2, 1)),
     )
-    def test_restart_markers(self, blocks, rows, markers) -> None:
+    def test_restart_markers(self, blocks: int, rows: int, markers: int) -> None:
         im = Image.new("RGB", (32, 32))  # 16 MCUs
         out = BytesIO()
         im.save(
@@ -724,13 +723,13 @@ class TestFileJpeg:
             assert im.format == "JPEG"
 
     @pytest.mark.parametrize("mode", ("1", "L", "RGB", "RGBX", "CMYK", "YCbCr"))
-    def test_save_correct_modes(self, mode) -> None:
+    def test_save_correct_modes(self, mode: str) -> None:
         out = BytesIO()
         img = Image.new(mode, (20, 20))
         img.save(out, "JPEG")
 
     @pytest.mark.parametrize("mode", ("LA", "La", "RGBA", "RGBa", "P"))
-    def test_save_wrong_modes(self, mode) -> None:
+    def test_save_wrong_modes(self, mode: str) -> None:
         # ref https://github.com/python-pillow/Pillow/issues/2005
         out = BytesIO()
         img = Image.new(mode, (20, 20))
@@ -982,12 +981,12 @@ class TestFileJpeg:
         # Even though this decoder never says that it is finished
         # the image should still end when there is no new data
         class InfiniteMockPyDecoder(ImageFile.PyDecoder):
-            def decode(self, buffer):
+            def decode(self, buffer: bytes) -> tuple[int, int]:
                 return 0, 0
 
         decoder = InfiniteMockPyDecoder(None)
 
-        def closure(mode, *args):
+        def closure(mode: str, *args) -> InfiniteMockPyDecoder:
             decoder.__init__(mode, *args)
             return decoder
 

Tests/test_file_jpeg2k.py

@@ -4,6 +4,7 @@ import os
 import re
 from io import BytesIO
 from pathlib import Path
+from typing import Any
 
 import pytest
 
@@ -36,7 +37,7 @@ test_card.load()
 # 'Not enough memory to handle tile data'
 
 
-def roundtrip(im, **options):
+def roundtrip(im: Image.Image, **options: Any) -> Image.Image:
     out = BytesIO()
     im.save(out, "JPEG2000", **options)
     test_bytes = out.tell()
@@ -138,7 +139,7 @@ def test_prog_res_rt() -> None:
 
 
 @pytest.mark.parametrize("num_resolutions", range(2, 6))
-def test_default_num_resolutions(num_resolutions) -> None:
+def test_default_num_resolutions(num_resolutions: int) -> None:
     d = 1 << (num_resolutions - 1)
     im = test_card.resize((d - 1, d - 1))
     with pytest.raises(OSError):
@@ -198,9 +199,9 @@ def test_layers_type(tmp_path: Path) -> None:
     for quality_layers in [[100, 50, 10], (100, 50, 10), None]:
         test_card.save(outfile, quality_layers=quality_layers)
 
-    for quality_layers in ["quality_layers", ("100", "50", "10")]:
+    for quality_layers_str in ["quality_layers", ("100", "50", "10")]:
         with pytest.raises(ValueError):
-            test_card.save(outfile, quality_layers=quality_layers)
+            test_card.save(outfile, quality_layers=quality_layers_str)
 
 
 def test_layers() -> None:
@@ -233,7 +234,7 @@ def test_layers() -> None:
         ("foo.jp2", {"no_jp2": False}, 4, b"jP"),
     ),
 )
-def test_no_jp2(name, args, offset, data) -> None:
+def test_no_jp2(name: str, args: dict[str, bool], offset: int, data: bytes) -> None:
     out = BytesIO()
     if name:
         out.name = name
@@ -278,7 +279,7 @@ def test_sgnd(tmp_path: Path) -> None:
 
 
 @pytest.mark.parametrize("ext", (".j2k", ".jp2"))
-def test_rgba(ext) -> None:
+def test_rgba(ext: str) -> None:
     # Arrange
     with Image.open("Tests/images/rgb_trns_ycbc" + ext) as im:
         # Act
@@ -289,7 +290,7 @@ def test_rgba(ext) -> None:
 
 
 @pytest.mark.parametrize("ext", (".j2k", ".jp2"))
-def test_16bit_monochrome_has_correct_mode(ext) -> None:
+def test_16bit_monochrome_has_correct_mode(ext: str) -> None:
     with Image.open("Tests/images/16bit.cropped" + ext) as im:
         im.load()
         assert im.mode == "I;16"
@@ -346,12 +347,12 @@ def test_parser_feed() -> None:
     not os.path.exists(EXTRA_DIR), reason="Extra image files not installed"
 )
 @pytest.mark.parametrize("name", ("subsampling_1", "subsampling_2", "zoo1", "zoo2"))
-def test_subsampling_decode(name) -> None:
+def test_subsampling_decode(name: str) -> None:
     test = f"{EXTRA_DIR}/{name}.jp2"
     reference = f"{EXTRA_DIR}/{name}.ppm"
 
     with Image.open(test) as im:
-        epsilon = 3  # for YCbCr images
+        epsilon = 3.0  # for YCbCr images
         with Image.open(reference) as im2:
             width, height = im2.size
             if name[-1] == "2":
@@ -400,7 +401,7 @@ def test_save_comment() -> None:
         "Tests/images/crash-d2c93af851d3ab9a19e34503626368b2ecde9c03.j2k",
     ],
 )
-def test_crashes(test_file) -> None:
+def test_crashes(test_file: str) -> None:
     with open(test_file, "rb") as f:
         with Image.open(f) as im:
             # Valgrind should not complain here

Tests/test_file_libtiff.py

@@ -27,7 +27,7 @@ from .helper import (
 
 @skip_unless_feature("libtiff")
 class LibTiffTestCase:
-    def _assert_noerr(self, tmp_path: Path, im) -> None:
+    def _assert_noerr(self, tmp_path: Path, im: Image.Image) -> None:
         """Helper tests that assert basic sanity about the g4 tiff reading"""
         # 1 bit
         assert im.mode == "1"
@@ -140,7 +140,7 @@ class TestFileLibTiff(LibTiffTestCase):
             assert_image_equal_tofile(im, "Tests/images/tiff_adobe_deflate.png")
 
     @pytest.mark.parametrize("legacy_api", (False, True))
-    def test_write_metadata(self, legacy_api, tmp_path: Path) -> None:
+    def test_write_metadata(self, legacy_api: bool, tmp_path: Path) -> None:
         """Test metadata writing through libtiff"""
         f = str(tmp_path / "temp.tiff")
         with Image.open("Tests/images/hopper_g4.tif") as img:
@@ -243,7 +243,7 @@ class TestFileLibTiff(LibTiffTestCase):
         TiffImagePlugin.WRITE_LIBTIFF = False
 
     def test_custom_metadata(self, tmp_path: Path) -> None:
-        tc = namedtuple("test_case", "value,type,supported_by_default")
+        tc = namedtuple("tc", "value,type,supported_by_default")
         custom = {
             37000 + k: v
             for k, v in enumerate(
@@ -284,7 +284,9 @@ class TestFileLibTiff(LibTiffTestCase):
         for libtiff in libtiffs:
             TiffImagePlugin.WRITE_LIBTIFF = libtiff
 
-            def check_tags(tiffinfo) -> None:
+            def check_tags(
+                tiffinfo: TiffImagePlugin.ImageFileDirectory_v2 | dict[int, str]
+            ) -> None:
                 im = hopper()
 
                 out = str(tmp_path / "temp.tif")
@@ -502,7 +504,7 @@ class TestFileLibTiff(LibTiffTestCase):
         assert_image_equal_tofile(im, out)
 
     @pytest.mark.parametrize("im", (hopper("P"), Image.new("P", (1, 1), "#000")))
-    def test_palette_save(self, im, tmp_path: Path) -> None:
+    def test_palette_save(self, im: Image.Image, tmp_path: Path) -> None:
         out = str(tmp_path / "temp.tif")
 
         TiffImagePlugin.WRITE_LIBTIFF = True
@@ -514,7 +516,7 @@ class TestFileLibTiff(LibTiffTestCase):
             assert len(reloaded.tag_v2[320]) == 768
 
     @pytest.mark.parametrize("compression", ("tiff_ccitt", "group3", "group4"))
-    def test_bw_compression_w_rgb(self, compression, tmp_path: Path) -> None:
+    def test_bw_compression_w_rgb(self, compression: str, tmp_path: Path) -> None:
         im = hopper("RGB")
         out = str(tmp_path / "temp.tif")
 
@@ -647,7 +649,7 @@ class TestFileLibTiff(LibTiffTestCase):
         # Generate test image
         pilim = hopper()
 
-        def save_bytesio(compression=None) -> None:
+        def save_bytesio(compression: str | None = None) -> None:
             buffer_io = io.BytesIO()
             pilim.save(buffer_io, format="tiff", compression=compression)
             buffer_io.seek(0)
@@ -731,7 +733,7 @@ class TestFileLibTiff(LibTiffTestCase):
         assert icc == icc_libtiff
 
     def test_write_icc(self, tmp_path: Path) -> None:
-        def check_write(libtiff) -> None:
+        def check_write(libtiff: bool) -> None:
             TiffImagePlugin.WRITE_LIBTIFF = libtiff
 
             with Image.open("Tests/images/hopper.iccprofile.tif") as img:
@@ -837,7 +839,7 @@ class TestFileLibTiff(LibTiffTestCase):
             assert reloaded.mode == "F"
             assert reloaded.getexif()[SAMPLEFORMAT] == 3
 
-    def test_lzma(self, capfd):
+    def test_lzma(self, capfd: pytest.CaptureFixture[str]) -> None:
         try:
             with Image.open("Tests/images/hopper_lzma.tif") as im:
                 assert im.mode == "RGB"
@@ -853,7 +855,7 @@ class TestFileLibTiff(LibTiffTestCase):
             sys.stderr.write(captured.err)
             raise
 
-    def test_webp(self, capfd):
+    def test_webp(self, capfd: pytest.CaptureFixture[str]) -> None:
         try:
             with Image.open("Tests/images/hopper_webp.tif") as im:
                 assert im.mode == "RGB"
@@ -971,7 +973,7 @@ class TestFileLibTiff(LibTiffTestCase):
             assert_image_equal_tofile(im, "Tests/images/tiff_16bit_RGBa_target.png")
 
     @pytest.mark.parametrize("compression", (None, "jpeg"))
-    def test_block_tile_tags(self, compression, tmp_path: Path) -> None:
+    def test_block_tile_tags(self, compression: str | None, tmp_path: Path) -> None:
         im = hopper()
         out = str(tmp_path / "temp.tif")
 
@@ -1020,7 +1022,9 @@ class TestFileLibTiff(LibTiffTestCase):
             ),
         ],
     )
-    def test_wrong_bits_per_sample(self, file_name, mode, size, tile) -> None:
+    def test_wrong_bits_per_sample(
+        self, file_name: str, mode: str, size: tuple[int, int], tile
+    ) -> None:
         with Image.open("Tests/images/" + file_name) as im:
             assert im.mode == mode
             assert im.size == size
@@ -1086,7 +1090,7 @@ class TestFileLibTiff(LibTiffTestCase):
         TiffImagePlugin.READ_LIBTIFF = False
 
     @pytest.mark.parametrize("compression", ("tiff_adobe_deflate", "jpeg"))
-    def test_save_multistrip(self, compression, tmp_path: Path) -> None:
+    def test_save_multistrip(self, compression: str, tmp_path: Path) -> None:
         im = hopper("RGB").resize((256, 256))
         out = str(tmp_path / "temp.tif")
         im.save(out, compression=compression)
@@ -1096,14 +1100,14 @@ class TestFileLibTiff(LibTiffTestCase):
             assert len(im.tag_v2[STRIPOFFSETS]) > 1
 
     @pytest.mark.parametrize("argument", (True, False))
-    def test_save_single_strip(self, argument, tmp_path: Path) -> None:
+    def test_save_single_strip(self, argument: bool, tmp_path: Path) -> None:
         im = hopper("RGB").resize((256, 256))
         out = str(tmp_path / "temp.tif")
 
         if not argument:
             TiffImagePlugin.STRIP_SIZE = 2**18
         try:
-            arguments = {"compression": "tiff_adobe_deflate"}
+            arguments: dict[str, str | int] = {"compression": "tiff_adobe_deflate"}
             if argument:
                 arguments["strip_size"] = 2**18
             im.save(out, **arguments)
@@ -1114,7 +1118,7 @@ class TestFileLibTiff(LibTiffTestCase):
             TiffImagePlugin.STRIP_SIZE = 65536
 
     @pytest.mark.parametrize("compression", ("tiff_adobe_deflate", None))
-    def test_save_zero(self, compression, tmp_path: Path) -> None:
+    def test_save_zero(self, compression: str | None, tmp_path: Path) -> None:
         im = Image.new("RGB", (0, 0))
         out = str(tmp_path / "temp.tif")
         with pytest.raises(SystemError):
@@ -1134,7 +1138,7 @@ class TestFileLibTiff(LibTiffTestCase):
             ("Tests/images/child_ifd_jpeg.tiff", (20,)),
         ),
     )
-    def test_get_child_images(self, path, sizes) -> None:
+    def test_get_child_images(self, path: str, sizes: tuple[int, ...]) -> None:
         with Image.open(path) as im:
             ims = im.get_child_images()
 

Tests/test_file_png.py

@@ -6,6 +6,7 @@ import warnings
 import zlib
 from io import BytesIO
 from pathlib import Path
+from typing import Any
 
 import pytest
 
@@ -36,7 +37,7 @@ TEST_PNG_FILE = "Tests/images/hopper.png"
 MAGIC = PngImagePlugin._MAGIC
 
 
-def chunk(cid, *data):
+def chunk(cid: bytes, *data: bytes) -> bytes:
     test_file = BytesIO()
     PngImagePlugin.putchunk(*(test_file, cid) + data)
     return test_file.getvalue()
@@ -52,11 +53,11 @@ HEAD = MAGIC + IHDR
 TAIL = IDAT + IEND
 
 
-def load(data):
+def load(data: bytes) -> Image.Image:
     return Image.open(BytesIO(data))
 
 
-def roundtrip(im, **options):
+def roundtrip(im: Image.Image, **options: Any) -> Image.Image:
     out = BytesIO()
     im.save(out, "PNG", **options)
     out.seek(0)
@@ -65,7 +66,7 @@ def roundtrip(im, **options):
 
 @skip_unless_feature("zlib")
 class TestFilePng:
-    def get_chunks(self, filename):
+    def get_chunks(self, filename: str) -> list[bytes]:
         chunks = []
         with open(filename, "rb") as fp:
             fp.read(8)
@@ -436,7 +437,7 @@ class TestFilePng:
     def test_unicode_text(self) -> None:
         # Check preservation of non-ASCII characters
 
-        def rt_text(value) -> None:
+        def rt_text(value: str) -> None:
             im = Image.new("RGB", (32, 32))
             info = PngImagePlugin.PngInfo()
             info.add_text("Text", value)
@@ -636,7 +637,7 @@ class TestFilePng:
     @pytest.mark.parametrize(
         "cid", (b"IHDR", b"sRGB", b"pHYs", b"acTL", b"fcTL", b"fdAT")
     )
-    def test_truncated_chunks(self, cid) -> None:
+    def test_truncated_chunks(self, cid: bytes) -> None:
         fp = BytesIO()
         with PngImagePlugin.PngStream(fp) as png:
             with pytest.raises(ValueError):
@@ -755,7 +756,7 @@ class TestFilePng:
                 im.seek(1)
 
     @pytest.mark.parametrize("buffer", (True, False))
-    def test_save_stdout(self, buffer) -> None:
+    def test_save_stdout(self, buffer: bool) -> None:
         old_stdout = sys.stdout
 
         if buffer:

Tests/test_image_paste.py

@@ -11,10 +11,9 @@ class TestImagingPaste:
     masks = {}
     size = 128
 
-    def assert_9points_image(self, im, expected) -> None:
+    def assert_9points_image(
-        expected = [
+        self, im: Image.Image, expected: list[tuple[int, int, int, int]]
-            point[0] if im.mode == "L" else point[: len(im.mode)] for point in expected
+    ) -> None:
-        ]
         px = im.load()
         actual = [
             px[0, 0],
@@ -27,9 +26,17 @@ class TestImagingPaste:
             px[self.size // 2, self.size - 1],
             px[self.size - 1, self.size - 1],
         ]
-        assert actual == expected
+        assert actual == [
+            point[0] if im.mode == "L" else point[: len(im.mode)] for point in expected
+        ]
 
-    def assert_9points_paste(self, im, im2, mask, expected) -> None:
+    def assert_9points_paste(
+        self,
+        im: Image.Image,
+        im2: Image.Image,
+        mask: Image.Image,
+        expected: list[tuple[int, int, int, int]],
+    ) -> None:
         im3 = im.copy()
         im3.paste(im2, (0, 0), mask)
         self.assert_9points_image(im3, expected)
@@ -106,7 +113,7 @@ class TestImagingPaste:
         )
 
     @pytest.mark.parametrize("mode", ["RGBA", "RGB", "L"])
-    def test_image_solid(self, mode) -> None:
+    def test_image_solid(self, mode: str) -> None:
         im = Image.new(mode, (200, 200), "red")
         im2 = getattr(self, "gradient_" + mode)
 
@@ -116,7 +123,7 @@ class TestImagingPaste:
         assert_image_equal(im, im2)
 
     @pytest.mark.parametrize("mode", ["RGBA", "RGB", "L"])
-    def test_image_mask_1(self, mode) -> None:
+    def test_image_mask_1(self, mode: str) -> None:
         im = Image.new(mode, (200, 200), "white")
         im2 = getattr(self, "gradient_" + mode)
 
@@ -138,7 +145,7 @@ class TestImagingPaste:
         )
 
     @pytest.mark.parametrize("mode", ["RGBA", "RGB", "L"])
-    def test_image_mask_L(self, mode) -> None:
+    def test_image_mask_L(self, mode: str) -> None:
         im = Image.new(mode, (200, 200), "white")
         im2 = getattr(self, "gradient_" + mode)
 
@@ -160,7 +167,7 @@ class TestImagingPaste:
         )
 
     @pytest.mark.parametrize("mode", ["RGBA", "RGB", "L"])
-    def test_image_mask_LA(self, mode) -> None:
+    def test_image_mask_LA(self, mode: str) -> None:
         im = Image.new(mode, (200, 200), "white")
         im2 = getattr(self, "gradient_" + mode)
 
@@ -182,7 +189,7 @@ class TestImagingPaste:
         )
 
     @pytest.mark.parametrize("mode", ["RGBA", "RGB", "L"])
-    def test_image_mask_RGBA(self, mode) -> None:
+    def test_image_mask_RGBA(self, mode: str) -> None:
         im = Image.new(mode, (200, 200), "white")
         im2 = getattr(self, "gradient_" + mode)
 
@@ -204,7 +211,7 @@ class TestImagingPaste:
         )
 
     @pytest.mark.parametrize("mode", ["RGBA", "RGB", "L"])
-    def test_image_mask_RGBa(self, mode) -> None:
+    def test_image_mask_RGBa(self, mode: str) -> None:
         im = Image.new(mode, (200, 200), "white")
         im2 = getattr(self, "gradient_" + mode)
 
@@ -226,7 +233,7 @@ class TestImagingPaste:
         )
 
     @pytest.mark.parametrize("mode", ["RGBA", "RGB", "L"])
-    def test_color_solid(self, mode) -> None:
+    def test_color_solid(self, mode: str) -> None:
         im = Image.new(mode, (200, 200), "black")
 
         rect = (12, 23, 128 + 12, 128 + 23)
@@ -239,7 +246,7 @@ class TestImagingPaste:
             assert sum(head[:255]) == 0
 
     @pytest.mark.parametrize("mode", ["RGBA", "RGB", "L"])
-    def test_color_mask_1(self, mode) -> None:
+    def test_color_mask_1(self, mode: str) -> None:
         im = Image.new(mode, (200, 200), (50, 60, 70, 80)[: len(mode)])
         color = (10, 20, 30, 40)[: len(mode)]
 
@@ -261,7 +268,7 @@ class TestImagingPaste:
         )
 
     @pytest.mark.parametrize("mode", ["RGBA", "RGB", "L"])
-    def test_color_mask_L(self, mode) -> None:
+    def test_color_mask_L(self, mode: str) -> None:
         im = getattr(self, "gradient_" + mode).copy()
         color = "white"
 
@@ -283,7 +290,7 @@ class TestImagingPaste:
         )
 
     @pytest.mark.parametrize("mode", ["RGBA", "RGB", "L"])
-    def test_color_mask_RGBA(self, mode) -> None:
+    def test_color_mask_RGBA(self, mode: str) -> None:
         im = getattr(self, "gradient_" + mode).copy()
         color = "white"
 
@@ -305,7 +312,7 @@ class TestImagingPaste:
         )
 
     @pytest.mark.parametrize("mode", ["RGBA", "RGB", "L"])
-    def test_color_mask_RGBa(self, mode) -> None:
+    def test_color_mask_RGBa(self, mode: str) -> None:
         im = getattr(self, "gradient_" + mode).copy()
         color = "white"
 

Tests/test_image_reduce.py

@@ -48,7 +48,7 @@ gradients_image.load()
         ((1, 3), (10, 4)),
     ),
 )
-def test_args_factor(size, expected) -> None:
+def test_args_factor(size: int | tuple[int, int], expected: tuple[int, int]) -> None:
     im = Image.new("L", (10, 10))
     assert expected == im.reduce(size).size
 
@@ -56,7 +56,7 @@ def test_args_factor(size, expected) -> None:
 @pytest.mark.parametrize(
     "size, expected_error", ((0, ValueError), (2.0, TypeError), ((0, 10), ValueError))
 )
-def test_args_factor_error(size, expected_error) -> None:
+def test_args_factor_error(size: float | tuple[int, int], expected_error) -> None:
     im = Image.new("L", (10, 10))
     with pytest.raises(expected_error):
         im.reduce(size)
@@ -69,7 +69,7 @@ def test_args_factor_error(size, expected_error) -> None:
         ((5, 5, 6, 6), (1, 1)),
     ),
 )
-def test_args_box(size, expected) -> None:
+def test_args_box(size: tuple[int, int, int, int], expected: tuple[int, int]) -> None:
     im = Image.new("L", (10, 10))
     assert expected == im.reduce(2, size).size
 
@@ -86,20 +86,20 @@ def test_args_box(size, expected) -> None:
         ((5, 0, 5, 10), ValueError),
     ),
 )
-def test_args_box_error(size, expected_error) -> None:
+def test_args_box_error(size: str | tuple[int, int, int, int], expected_error) -> None:
     im = Image.new("L", (10, 10))
     with pytest.raises(expected_error):
         im.reduce(2, size).size
 
 
 @pytest.mark.parametrize("mode", ("P", "1", "I;16"))
-def test_unsupported_modes(mode) -> None:
+def test_unsupported_modes(mode: str) -> None:
     im = Image.new("P", (10, 10))
     with pytest.raises(ValueError):
         im.reduce(3)
 
 
-def get_image(mode):
+def get_image(mode: str) -> Image.Image:
     mode_info = ImageMode.getmode(mode)
     if mode_info.basetype == "L":
         bands = [gradients_image]
@@ -119,7 +119,7 @@ def get_image(mode):
     return im.crop((0, 0, im.width, im.height - 5))
 
 
-def compare_reduce_with_box(im, factor) -> None:
+def compare_reduce_with_box(im: Image.Image, factor: int | tuple[int, int]) -> None:
     box = (11, 13, 146, 164)
     reduced = im.reduce(factor, box=box)
     reference = im.crop(box).reduce(factor)
@@ -127,7 +127,10 @@ def compare_reduce_with_box(im, factor) -> None:
 
 
 def compare_reduce_with_reference(
-    im, factor, average_diff: float = 0.4, max_diff: int = 1
+    im: Image.Image,
+    factor: int | tuple[int, int],
+    average_diff: float = 0.4,
+    max_diff: int = 1,
 ) -> None:
     """Image.reduce() should look very similar to Image.resize(BOX).
 
@@ -173,7 +176,9 @@ def compare_reduce_with_reference(
     assert_compare_images(reduced, reference, average_diff, max_diff)
 
 
-def assert_compare_images(a, b, max_average_diff, max_diff: int = 255) -> None:
+def assert_compare_images(
+    a: Image.Image, b: Image.Image, max_average_diff: float, max_diff: int = 255
+) -> None:
     assert a.mode == b.mode, f"got mode {repr(a.mode)}, expected {repr(b.mode)}"
     assert a.size == b.size, f"got size {repr(a.size)}, expected {repr(b.size)}"
 
@@ -201,20 +206,20 @@ def assert_compare_images(a, b, max_average_diff, max_diff: int = 255) -> None:
 
 
 @pytest.mark.parametrize("factor", remarkable_factors)
-def test_mode_L(factor) -> None:
+def test_mode_L(factor: int | tuple[int, int]) -> None:
     im = get_image("L")
     compare_reduce_with_reference(im, factor)
     compare_reduce_with_box(im, factor)
 
 
 @pytest.mark.parametrize("factor", remarkable_factors)
-def test_mode_LA(factor) -> None:
+def test_mode_LA(factor: int | tuple[int, int]) -> None:
     im = get_image("LA")
     compare_reduce_with_reference(im, factor, 0.8, 5)
 
 
 @pytest.mark.parametrize("factor", remarkable_factors)
-def test_mode_LA_opaque(factor) -> None:
+def test_mode_LA_opaque(factor: int | tuple[int, int]) -> None:
     im = get_image("LA")
     # With opaque alpha, an error should be way smaller.
     im.putalpha(Image.new("L", im.size, 255))
@@ -223,27 +228,27 @@ def test_mode_LA_opaque(factor) -> None:
 
 
 @pytest.mark.parametrize("factor", remarkable_factors)
-def test_mode_La(factor) -> None:
+def test_mode_La(factor: int | tuple[int, int]) -> None:
     im = get_image("La")
     compare_reduce_with_reference(im, factor)
     compare_reduce_with_box(im, factor)
 
 
 @pytest.mark.parametrize("factor", remarkable_factors)
-def test_mode_RGB(factor) -> None:
+def test_mode_RGB(factor: int | tuple[int, int]) -> None:
     im = get_image("RGB")
     compare_reduce_with_reference(im, factor)
     compare_reduce_with_box(im, factor)
 
 
 @pytest.mark.parametrize("factor", remarkable_factors)
-def test_mode_RGBA(factor) -> None:
+def test_mode_RGBA(factor: int | tuple[int, int]) -> None:
     im = get_image("RGBA")
     compare_reduce_with_reference(im, factor, 0.8, 5)
 
 
 @pytest.mark.parametrize("factor", remarkable_factors)
-def test_mode_RGBA_opaque(factor) -> None:
+def test_mode_RGBA_opaque(factor: int | tuple[int, int]) -> None:
     im = get_image("RGBA")
     # With opaque alpha, an error should be way smaller.
     im.putalpha(Image.new("L", im.size, 255))
@@ -252,21 +257,21 @@ def test_mode_RGBA_opaque(factor) -> None:
 
 
 @pytest.mark.parametrize("factor", remarkable_factors)
-def test_mode_RGBa(factor) -> None:
+def test_mode_RGBa(factor: int | tuple[int, int]) -> None:
     im = get_image("RGBa")
     compare_reduce_with_reference(im, factor)
     compare_reduce_with_box(im, factor)
 
 
 @pytest.mark.parametrize("factor", remarkable_factors)
-def test_mode_I(factor) -> None:
+def test_mode_I(factor: int | tuple[int, int]) -> None:
     im = get_image("I")
     compare_reduce_with_reference(im, factor)
     compare_reduce_with_box(im, factor)
 
 
 @pytest.mark.parametrize("factor", remarkable_factors)
-def test_mode_F(factor) -> None:
+def test_mode_F(factor: int | tuple[int, int]) -> None:
     im = get_image("F")
     compare_reduce_with_reference(im, factor, 0, 0)
     compare_reduce_with_box(im, factor)

Tests/test_image_resample.py

@@ -1,6 +1,7 @@
 from __future__ import annotations
 
 from contextlib import contextmanager
+from typing import Generator
 
 import pytest
 
@@ -51,7 +52,7 @@ class TestImagingResampleVulnerability:
 
 
 class TestImagingCoreResampleAccuracy:
-    def make_case(self, mode, size, color):
+    def make_case(self, mode: str, size: tuple[int, int], color: int) -> Image.Image:
         """Makes a sample image with two dark and two bright squares.
         For example:
         e0 e0 1f 1f
@@ -66,7 +67,7 @@ class TestImagingCoreResampleAccuracy:
 
         return Image.merge(mode, [case] * len(mode))
 
-    def make_sample(self, data, size):
+    def make_sample(self, data: str, size: tuple[int, int]) -> Image.Image:
         """Restores a sample image from given data string which contains
         hex-encoded pixels from the top left fourth of a sample.
         """
@@ -83,7 +84,7 @@ class TestImagingCoreResampleAccuracy:
                 s_px[size[0] - x - 1, y] = 255 - val
         return sample
 
-    def check_case(self, case, sample) -> None:
+    def check_case(self, case: Image.Image, sample: Image.Image) -> None:
         s_px = sample.load()
         c_px = case.load()
         for y in range(case.size[1]):
@@ -95,7 +96,7 @@ class TestImagingCoreResampleAccuracy:
                     )
                     assert s_px[x, y] == c_px[x, y], message
 
-    def serialize_image(self, image):
+    def serialize_image(self, image: Image.Image) -> str:
         s_px = image.load()
         return "\n".join(
             " ".join(f"{s_px[x, y]:02x}" for x in range(image.size[0]))
@@ -103,7 +104,7 @@ class TestImagingCoreResampleAccuracy:
         )
 
     @pytest.mark.parametrize("mode", ("RGBX", "RGB", "La", "L"))
-    def test_reduce_box(self, mode) -> None:
+    def test_reduce_box(self, mode: str) -> None:
         case = self.make_case(mode, (8, 8), 0xE1)
         case = case.resize((4, 4), Image.Resampling.BOX)
         # fmt: off
@@ -114,7 +115,7 @@ class TestImagingCoreResampleAccuracy:
             self.check_case(channel, self.make_sample(data, (4, 4)))
 
     @pytest.mark.parametrize("mode", ("RGBX", "RGB", "La", "L"))
-    def test_reduce_bilinear(self, mode) -> None:
+    def test_reduce_bilinear(self, mode: str) -> None:
         case = self.make_case(mode, (8, 8), 0xE1)
         case = case.resize((4, 4), Image.Resampling.BILINEAR)
         # fmt: off
@@ -125,7 +126,7 @@ class TestImagingCoreResampleAccuracy:
             self.check_case(channel, self.make_sample(data, (4, 4)))
 
     @pytest.mark.parametrize("mode", ("RGBX", "RGB", "La", "L"))
-    def test_reduce_hamming(self, mode) -> None:
+    def test_reduce_hamming(self, mode: str) -> None:
         case = self.make_case(mode, (8, 8), 0xE1)
         case = case.resize((4, 4), Image.Resampling.HAMMING)
         # fmt: off
@@ -136,7 +137,7 @@ class TestImagingCoreResampleAccuracy:
             self.check_case(channel, self.make_sample(data, (4, 4)))
 
     @pytest.mark.parametrize("mode", ("RGBX", "RGB", "La", "L"))
-    def test_reduce_bicubic(self, mode) -> None:
+    def test_reduce_bicubic(self, mode: str) -> None:
         case = self.make_case(mode, (12, 12), 0xE1)
         case = case.resize((6, 6), Image.Resampling.BICUBIC)
         # fmt: off
@@ -148,7 +149,7 @@ class TestImagingCoreResampleAccuracy:
             self.check_case(channel, self.make_sample(data, (6, 6)))
 
     @pytest.mark.parametrize("mode", ("RGBX", "RGB", "La", "L"))
-    def test_reduce_lanczos(self, mode) -> None:
+    def test_reduce_lanczos(self, mode: str) -> None:
         case = self.make_case(mode, (16, 16), 0xE1)
         case = case.resize((8, 8), Image.Resampling.LANCZOS)
         # fmt: off
@@ -161,7 +162,7 @@ class TestImagingCoreResampleAccuracy:
             self.check_case(channel, self.make_sample(data, (8, 8)))
 
     @pytest.mark.parametrize("mode", ("RGBX", "RGB", "La", "L"))
-    def test_enlarge_box(self, mode) -> None:
+    def test_enlarge_box(self, mode: str) -> None:
         case = self.make_case(mode, (2, 2), 0xE1)
         case = case.resize((4, 4), Image.Resampling.BOX)
         # fmt: off
@@ -172,7 +173,7 @@ class TestImagingCoreResampleAccuracy:
             self.check_case(channel, self.make_sample(data, (4, 4)))
 
     @pytest.mark.parametrize("mode", ("RGBX", "RGB", "La", "L"))
-    def test_enlarge_bilinear(self, mode) -> None:
+    def test_enlarge_bilinear(self, mode: str) -> None:
         case = self.make_case(mode, (2, 2), 0xE1)
         case = case.resize((4, 4), Image.Resampling.BILINEAR)
         # fmt: off
@@ -183,7 +184,7 @@ class TestImagingCoreResampleAccuracy:
             self.check_case(channel, self.make_sample(data, (4, 4)))
 
     @pytest.mark.parametrize("mode", ("RGBX", "RGB", "La", "L"))
-    def test_enlarge_hamming(self, mode) -> None:
+    def test_enlarge_hamming(self, mode: str) -> None:
         case = self.make_case(mode, (2, 2), 0xE1)
         case = case.resize((4, 4), Image.Resampling.HAMMING)
         # fmt: off
@@ -194,7 +195,7 @@ class TestImagingCoreResampleAccuracy:
             self.check_case(channel, self.make_sample(data, (4, 4)))
 
     @pytest.mark.parametrize("mode", ("RGBX", "RGB", "La", "L"))
-    def test_enlarge_bicubic(self, mode) -> None:
+    def test_enlarge_bicubic(self, mode: str) -> None:
         case = self.make_case(mode, (4, 4), 0xE1)
         case = case.resize((8, 8), Image.Resampling.BICUBIC)
         # fmt: off
@@ -207,7 +208,7 @@ class TestImagingCoreResampleAccuracy:
             self.check_case(channel, self.make_sample(data, (8, 8)))
 
     @pytest.mark.parametrize("mode", ("RGBX", "RGB", "La", "L"))
-    def test_enlarge_lanczos(self, mode) -> None:
+    def test_enlarge_lanczos(self, mode: str) -> None:
         case = self.make_case(mode, (6, 6), 0xE1)
         case = case.resize((12, 12), Image.Resampling.LANCZOS)
         data = (
@@ -230,7 +231,7 @@ class TestImagingCoreResampleAccuracy:
 
 
 class TestCoreResampleConsistency:
-    def make_case(self, mode, fill):
+    def make_case(self, mode: str, fill: tuple[int, int, int] | float):
         im = Image.new(mode, (512, 9), fill)
         return im.resize((9, 512), Image.Resampling.LANCZOS), im.load()[0, 0]
 
@@ -265,7 +266,7 @@ class TestCoreResampleConsistency:
 
 
 class TestCoreResampleAlphaCorrect:
-    def make_levels_case(self, mode):
+    def make_levels_case(self, mode: str) -> Image.Image:
         i = Image.new(mode, (256, 16))
         px = i.load()
         for y in range(i.size[1]):
@@ -275,7 +276,7 @@ class TestCoreResampleAlphaCorrect:
                 px[x, y] = tuple(pix)
         return i
 
-    def run_levels_case(self, i) -> None:
+    def run_levels_case(self, i: Image.Image) -> None:
         px = i.load()
         for y in range(i.size[1]):
             used_colors = {px[x, y][0] for x in range(i.size[0])}
@@ -302,7 +303,9 @@ class TestCoreResampleAlphaCorrect:
         self.run_levels_case(case.resize((512, 32), Image.Resampling.BICUBIC))
         self.run_levels_case(case.resize((512, 32), Image.Resampling.LANCZOS))
 
-    def make_dirty_case(self, mode, clean_pixel, dirty_pixel):
+    def make_dirty_case(
+        self, mode: str, clean_pixel: tuple[int, ...], dirty_pixel: tuple[int, ...]
+    ) -> Image.Image:
         i = Image.new(mode, (64, 64), dirty_pixel)
         px = i.load()
         xdiv4 = i.size[0] // 4
@@ -312,7 +315,7 @@ class TestCoreResampleAlphaCorrect:
                 px[x + xdiv4, y + ydiv4] = clean_pixel
         return i
 
-    def run_dirty_case(self, i, clean_pixel) -> None:
+    def run_dirty_case(self, i: Image.Image, clean_pixel: tuple[int, ...]) -> None:
         px = i.load()
         for y in range(i.size[1]):
             for x in range(i.size[0]):
@@ -432,7 +435,7 @@ class TestCoreResampleBox:
             Image.Resampling.LANCZOS,
         ),
     )
-    def test_wrong_arguments(self, resample) -> None:
+    def test_wrong_arguments(self, resample: Image.Resampling) -> None:
         im = hopper()
         im.resize((32, 32), resample, (0, 0, im.width, im.height))
         im.resize((32, 32), resample, (20, 20, im.width, im.height))
@@ -459,8 +462,12 @@ class TestCoreResampleBox:
         with pytest.raises(ValueError, match="can't exceed"):
             im.resize((32, 32), resample, (0, 0, im.width, im.height + 1))
 
-    def resize_tiled(self, im, dst_size, xtiles, ytiles):
+    def resize_tiled(
-        def split_range(size, tiles):
+        self, im: Image.Image, dst_size: tuple[int, int], xtiles: int, ytiles: int
+    ) -> Image.Image:
+        def split_range(
+            size: int, tiles: int
+        ) -> Generator[tuple[int, int], None, None]:
             scale = size / tiles
             for i in range(tiles):
                 yield int(round(scale * i)), int(round(scale * (i + 1)))
@@ -518,7 +525,7 @@ class TestCoreResampleBox:
     @pytest.mark.parametrize(
         "resample", (Image.Resampling.NEAREST, Image.Resampling.BILINEAR)
     )
-    def test_formats(self, mode, resample) -> None:
+    def test_formats(self, mode: str, resample: Image.Resampling) -> None:
         im = hopper(mode)
         box = (20, 20, im.size[0] - 20, im.size[1] - 20)
         with_box = im.resize((32, 32), resample, box)
@@ -558,7 +565,7 @@ class TestCoreResampleBox:
     @pytest.mark.parametrize(
         "flt", (Image.Resampling.NEAREST, Image.Resampling.BICUBIC)
     )
-    def test_skip_horizontal(self, flt) -> None:
+    def test_skip_horizontal(self, flt: Image.Resampling) -> None:
         # Can skip resize for one dimension
         im = hopper()
 
@@ -581,7 +588,7 @@ class TestCoreResampleBox:
     @pytest.mark.parametrize(
         "flt", (Image.Resampling.NEAREST, Image.Resampling.BICUBIC)
     )
-    def test_skip_vertical(self, flt) -> None:
+    def test_skip_vertical(self, flt: Image.Resampling) -> None:
         # Can skip resize for one dimension
         im = hopper()
 

Tests/test_imagemath.py

@@ -5,12 +5,12 @@ import pytest
 from PIL import Image, ImageMath
 
 
-def pixel(im):
+def pixel(im: Image.Image | int) -> str | int:
-    if hasattr(im, "im"):
-        return f"{im.mode} {repr(im.getpixel((0, 0)))}"
     if isinstance(im, int):
         return int(im)  # hack to deal with booleans
 
+    return f"{im.mode} {repr(im.getpixel((0, 0)))}"
+
 
 A = Image.new("L", (1, 1), 1)
 B = Image.new("L", (1, 1), 2)
@@ -60,7 +60,7 @@ def test_ops() -> None:
         "(lambda: (lambda: exec('pass'))())()",
     ),
 )
-def test_prevent_exec(expression) -> None:
+def test_prevent_exec(expression: str) -> None:
     with pytest.raises(ValueError):
         ImageMath.eval(expression)
 

pyproject.toml

@@ -141,16 +141,6 @@ warn_redundant_casts = true
 warn_unreachable = true
 warn_unused_ignores = true
 exclude = [
-  '^src/PIL/_tkinter_finder.py$',
-  '^src/PIL/DdsImagePlugin.py$',
   '^src/PIL/FpxImagePlugin.py$',
-  '^src/PIL/Image.py$',
-  '^src/PIL/ImageQt.py$',
-  '^src/PIL/ImImagePlugin.py$',
   '^src/PIL/MicImagePlugin.py$',
-  '^src/PIL/PdfParser.py$',
-  '^src/PIL/PyAccess.py$',
-  '^src/PIL/TiffImagePlugin.py$',
-  '^src/PIL/TiffTags.py$',
-  '^src/PIL/WebPImagePlugin.py$',
 ]

src/PIL/DdsImagePlugin.py

@@ -270,13 +270,17 @@ class D3DFMT(IntEnum):
 # Backward compatibility layer
 module = sys.modules[__name__]
 for item in DDSD:
+    assert item.name is not None
     setattr(module, "DDSD_" + item.name, item.value)
-for item in DDSCAPS:
+for item1 in DDSCAPS:
-    setattr(module, "DDSCAPS_" + item.name, item.value)
+    assert item1.name is not None
-for item in DDSCAPS2:
+    setattr(module, "DDSCAPS_" + item1.name, item1.value)
-    setattr(module, "DDSCAPS2_" + item.name, item.value)
+for item2 in DDSCAPS2:
-for item in DDPF:
+    assert item2.name is not None
-    setattr(module, "DDPF_" + item.name, item.value)
+    setattr(module, "DDSCAPS2_" + item2.name, item2.value)
+for item3 in DDPF:
+    assert item3.name is not None
+    setattr(module, "DDPF_" + item3.name, item3.value)
 
 DDS_FOURCC = DDPF.FOURCC
 DDS_RGB = DDPF.RGB

src/PIL/ImImagePlugin.py

@@ -93,8 +93,8 @@ for i in ["16", "16L", "16B"]:
 for i in ["32S"]:
     OPEN[f"L {i} image"] = ("I", f"I;{i}")
     OPEN[f"L*{i} image"] = ("I", f"I;{i}")
-for i in range(2, 33):
+for j in range(2, 33):
-    OPEN[f"L*{i} image"] = ("F", f"F;{i}")
+    OPEN[f"L*{j} image"] = ("F", f"F;{j}")
 
 
 # --------------------------------------------------------------------

src/PIL/Image.py

@@ -26,6 +26,7 @@
 
 from __future__ import annotations
 
+import abc
 import atexit
 import builtins
 import io
@@ -39,11 +40,8 @@ import tempfile
 import warnings
 from collections.abc import Callable, MutableMapping
 from enum import IntEnum
-
+from types import ModuleType
-try:
+from typing import IO, TYPE_CHECKING, Any
-    from defusedxml import ElementTree
-except ImportError:
-    ElementTree = None
 
 # VERSION was removed in Pillow 6.0.0.
 # PILLOW_VERSION was removed in Pillow 9.0.0.
@@ -59,6 +57,12 @@ from . import (
 from ._binary import i32le, o32be, o32le
 from ._util import DeferredError, is_path
 
+ElementTree: ModuleType | None
+try:
+    from defusedxml import ElementTree
+except ImportError:
+    ElementTree = None
+
 logger = logging.getLogger(__name__)
 
 
@@ -109,6 +113,7 @@ except ImportError as v:
 
 
 USE_CFFI_ACCESS = False
+cffi: ModuleType | None
 try:
     import cffi
 except ImportError:
@@ -210,14 +215,22 @@ if hasattr(core, "DEFAULT_STRATEGY"):
 # --------------------------------------------------------------------
 # Registries
 
-ID = []
+if TYPE_CHECKING:
-OPEN = {}
+    from . import ImageFile
-MIME = {}
+ID: list[str] = []
-SAVE = {}
+OPEN: dict[
-SAVE_ALL = {}
+    str,
-EXTENSION = {}
+    tuple[
-DECODERS = {}
+        Callable[[IO[bytes], str | bytes], ImageFile.ImageFile],
-ENCODERS = {}
+        Callable[[bytes], bool] | None,
+    ],
+] = {}
+MIME: dict[str, str] = {}
+SAVE: dict[str, Callable[[Image, IO[bytes], str | bytes], None]] = {}
+SAVE_ALL: dict[str, Callable[[Image, IO[bytes], str | bytes], None]] = {}
+EXTENSION: dict[str, str] = {}
+DECODERS: dict[str, object] = {}
+ENCODERS: dict[str, object] = {}
 
 # --------------------------------------------------------------------
 # Modes
@@ -2382,7 +2395,7 @@ class Image:
            may have been created, and may contain partial data.
         """
 
-        filename = ""
+        filename: str | bytes = ""
         open_fp = False
         if is_path(fp):
             filename = os.path.realpath(os.fspath(fp))
@@ -2394,7 +2407,7 @@ class Image:
                 pass
         if not filename and hasattr(fp, "name") and is_path(fp.name):
             # only set the name for metadata purposes
-            filename = fp.name
+            filename = os.path.realpath(os.fspath(fp.name))
 
         # may mutate self!
         self._ensure_mutable()
@@ -2405,7 +2418,8 @@ class Image:
 
         preinit()
 
-        ext = os.path.splitext(filename)[1].lower()
+        filename_ext = os.path.splitext(filename)[1].lower()
+        ext = filename_ext.decode() if isinstance(filename_ext, bytes) else filename_ext
 
         if not format:
             if ext not in EXTENSION:
@@ -2447,7 +2461,7 @@ class Image:
         if open_fp:
             fp.close()
 
-    def seek(self, frame) -> Image:
+    def seek(self, frame) -> None:
         """
         Seeks to the given frame in this sequence file. If you seek
         beyond the end of the sequence, the method raises an
@@ -2507,10 +2521,8 @@ class Image:
 
         self.load()
         if self.im.bands == 1:
-            ims = [self.copy()]
+            return (self.copy(),)
-        else:
+        return tuple(map(self._new, self.im.split()))
-            ims = map(self._new, self.im.split())
-        return tuple(ims)
 
     def getchannel(self, channel):
         """
@@ -2867,6 +2879,13 @@ class ImageTransformHandler:
     (for use with :py:meth:`~PIL.Image.Image.transform`)
     """
 
+    @abc.abstractmethod
+    def transform(
+        self,
+        size: tuple[int, int],
+        image: Image,
+        **options: dict[str, str | int | tuple[int, ...] | list[int]],
+    ) -> Image:
         pass
 
 
@@ -3239,7 +3258,7 @@ def open(fp, mode="r", formats=None) -> Image:
         raise TypeError(msg)
 
     exclusive_fp = False
-    filename = ""
+    filename: str | bytes = ""
     if is_path(fp):
         filename = os.path.realpath(os.fspath(fp))
 
@@ -3415,7 +3434,11 @@ def merge(mode, bands):
 # Plugin registry
 
 
-def register_open(id, factory, accept=None) -> None:
+def register_open(
+    id,
+    factory: Callable[[IO[bytes], str | bytes], ImageFile.ImageFile],
+    accept: Callable[[bytes], bool] | None = None,
+) -> None:
     """
     Register an image file plugin.  This function should not be used
     in application code.
@@ -3625,7 +3648,13 @@ _apply_env_variables()
 atexit.register(core.clear_cache)
 
 
-class Exif(MutableMapping):
+if TYPE_CHECKING:
+    _ExifBase = MutableMapping[int, Any]
+else:
+    _ExifBase = MutableMapping
+
+
+class Exif(_ExifBase):
     """
     This class provides read and write access to EXIF image data::
 

src/PIL/ImageQt.py

@@ -19,19 +19,26 @@ from __future__ import annotations
 
 import sys
 from io import BytesIO
+from typing import Callable
 
 from . import Image
 from ._util import is_path
 
+qt_version: str | None
 qt_versions = [
     ["6", "PyQt6"],
     ["side6", "PySide6"],
 ]
 
 # If a version has already been imported, attempt it first
-qt_versions.sort(key=lambda qt_version: qt_version[1] in sys.modules, reverse=True)
+qt_versions.sort(key=lambda version: version[1] in sys.modules, reverse=True)
-for qt_version, qt_module in qt_versions:
+for version, qt_module in qt_versions:
     try:
+        QBuffer: type
+        QIODevice: type
+        QImage: type
+        QPixmap: type
+        qRgba: Callable[[int, int, int, int], int]
         if qt_module == "PyQt6":
             from PyQt6.QtCore import QBuffer, QIODevice
             from PyQt6.QtGui import QImage, QPixmap, qRgba
@@ -41,6 +48,7 @@ for qt_version, qt_module in qt_versions:
     except (ImportError, RuntimeError):
         continue
     qt_is_installed = True
+    qt_version = version
     break
 else:
     qt_is_installed = False

src/PIL/ImageShow.py

@@ -184,7 +184,7 @@ class UnixViewer(Viewer):
 
     @abc.abstractmethod
     def get_command_ex(self, file: str, **options: Any) -> tuple[str, str]:
-        pass  # pragma: no cover
+        pass
 
     def get_command(self, file: str, **options: Any) -> str:
         command = self.get_command_ex(file, **options)[0]

src/PIL/PdfParser.py

@@ -8,6 +8,7 @@ import os
 import re
 import time
 import zlib
+from typing import TYPE_CHECKING, Any, List, Union
 
 
 # see 7.9.2.2 Text String Type on page 86 and D.3 PDFDocEncoding Character Set
@@ -239,12 +240,18 @@ class PdfName:
         return bytes(result)
 
 
-class PdfArray(list):
+class PdfArray(List[Any]):
     def __bytes__(self):
         return b"[ " + b" ".join(pdf_repr(x) for x in self) + b" ]"
 
 
-class PdfDict(collections.UserDict):
+if TYPE_CHECKING:
+    _DictBase = collections.UserDict[Union[str, bytes], Any]
+else:
+    _DictBase = collections.UserDict
+
+
+class PdfDict(_DictBase):
     def __setattr__(self, key, value):
         if key == "data":
             collections.UserDict.__setattr__(self, key, value)

src/PIL/PyAccess.py

@@ -25,6 +25,7 @@ import sys
 
 from ._deprecate import deprecate
 
+FFI: type
 try:
     from cffi import FFI
 

src/PIL/TiffImagePlugin.py

@@ -50,6 +50,7 @@ import warnings
 from collections.abc import MutableMapping
 from fractions import Fraction
 from numbers import Number, Rational
+from typing import TYPE_CHECKING, Any, Callable
 
 from . import ExifTags, Image, ImageFile, ImageOps, ImagePalette, TiffTags
 from ._binary import i16be as i16
@@ -306,6 +307,13 @@ _load_dispatch = {}
 _write_dispatch = {}
 
 
+def _delegate(op):
+    def delegate(self, *args):
+        return getattr(self._val, op)(*args)
+
+    return delegate
+
+
 class IFDRational(Rational):
     """Implements a rational class where 0/0 is a legal value to match
     the in the wild use of exif rationals.
@@ -391,12 +399,6 @@ class IFDRational(Rational):
         self._numerator = _numerator
         self._denominator = _denominator
 
-    def _delegate(op):
-        def delegate(self, *args):
-            return getattr(self._val, op)(*args)
-
-        return delegate
-
     """ a = ['add','radd', 'sub', 'rsub', 'mul', 'rmul',
              'truediv', 'rtruediv', 'floordiv', 'rfloordiv',
              'mod','rmod', 'pow','rpow', 'pos', 'neg',
@@ -436,7 +438,50 @@ class IFDRational(Rational):
         __int__ = _delegate("__int__")
 
 
-class ImageFileDirectory_v2(MutableMapping):
+def _register_loader(idx, size):
+    def decorator(func):
+        from .TiffTags import TYPES
+
+        if func.__name__.startswith("load_"):
+            TYPES[idx] = func.__name__[5:].replace("_", " ")
+        _load_dispatch[idx] = size, func  # noqa: F821
+        return func
+
+    return decorator
+
+
+def _register_writer(idx):
+    def decorator(func):
+        _write_dispatch[idx] = func  # noqa: F821
+        return func
+
+    return decorator
+
+
+def _register_basic(idx_fmt_name):
+    from .TiffTags import TYPES
+
+    idx, fmt, name = idx_fmt_name
+    TYPES[idx] = name
+    size = struct.calcsize("=" + fmt)
+    _load_dispatch[idx] = (  # noqa: F821
+        size,
+        lambda self, data, legacy_api=True: (
+            self._unpack(f"{len(data) // size}{fmt}", data)
+        ),
+    )
+    _write_dispatch[idx] = lambda self, *values: (  # noqa: F821
+        b"".join(self._pack(fmt, value) for value in values)
+    )
+
+
+if TYPE_CHECKING:
+    _IFDv2Base = MutableMapping[int, Any]
+else:
+    _IFDv2Base = MutableMapping
+
+
+class ImageFileDirectory_v2(_IFDv2Base):
     """This class represents a TIFF tag directory.  To speed things up, we
     don't decode tags unless they're asked for.
 
@@ -497,6 +542,9 @@ class ImageFileDirectory_v2(MutableMapping):
 
     """
 
+    _load_dispatch: dict[int, Callable[[ImageFileDirectory_v2, bytes, bool], Any]] = {}
+    _write_dispatch: dict[int, Callable[..., Any]] = {}
+
     def __init__(self, ifh=b"II\052\0\0\0\0\0", prefix=None, group=None):
         """Initialize an ImageFileDirectory.
 
@@ -531,7 +579,10 @@ class ImageFileDirectory_v2(MutableMapping):
 
     prefix = property(lambda self: self._prefix)
     offset = property(lambda self: self._offset)
-    legacy_api = property(lambda self: self._legacy_api)
+
+    @property
+    def legacy_api(self):
+        return self._legacy_api
 
     @legacy_api.setter
     def legacy_api(self, value):
@@ -674,40 +725,6 @@ class ImageFileDirectory_v2(MutableMapping):
     def _pack(self, fmt, *values):
         return struct.pack(self._endian + fmt, *values)
 
-    def _register_loader(idx, size):
-        def decorator(func):
-            from .TiffTags import TYPES
-
-            if func.__name__.startswith("load_"):
-                TYPES[idx] = func.__name__[5:].replace("_", " ")
-            _load_dispatch[idx] = size, func  # noqa: F821
-            return func
-
-        return decorator
-
-    def _register_writer(idx):
-        def decorator(func):
-            _write_dispatch[idx] = func  # noqa: F821
-            return func
-
-        return decorator
-
-    def _register_basic(idx_fmt_name):
-        from .TiffTags import TYPES
-
-        idx, fmt, name = idx_fmt_name
-        TYPES[idx] = name
-        size = struct.calcsize("=" + fmt)
-        _load_dispatch[idx] = (  # noqa: F821
-            size,
-            lambda self, data, legacy_api=True: (
-                self._unpack(f"{len(data) // size}{fmt}", data)
-            ),
-        )
-        _write_dispatch[idx] = lambda self, *values: (  # noqa: F821
-            b"".join(self._pack(fmt, value) for value in values)
-        )
-
     list(
         map(
             _register_basic,
@@ -995,7 +1012,7 @@ class ImageFileDirectory_v1(ImageFileDirectory_v2):
     tagdata = property(lambda self: self._tagdata)
 
     # defined in ImageFileDirectory_v2
-    tagtype: dict
+    tagtype: dict[int, int]
     """Dictionary of tag types"""
 
     @classmethod
@@ -1835,11 +1852,11 @@ def _save(im, fp, filename):
         tags = list(atts.items())
         tags.sort()
         a = (rawmode, compression, _fp, filename, tags, types)
-        e = Image._getencoder(im.mode, "libtiff", a, encoderconfig)
+        encoder = Image._getencoder(im.mode, "libtiff", a, encoderconfig)
-        e.setimage(im.im, (0, 0) + im.size)
+        encoder.setimage(im.im, (0, 0) + im.size)
         while True:
             # undone, change to self.decodermaxblock:
-            errcode, data = e.encode(16 * 1024)[1:]
+            errcode, data = encoder.encode(16 * 1024)[1:]
             if not _fp:
                 fp.write(data)
             if errcode:

src/PIL/TiffTags.py

@@ -22,7 +22,7 @@ from collections import namedtuple
 
 
 class TagInfo(namedtuple("_TagInfo", "value name type length enum")):
-    __slots__ = []
+    __slots__: list[str] = []
 
     def __new__(cls, value=None, name="unknown", type=None, length=None, enum=None):
         return super().__new__(cls, value, name, type, length, enum or {})
@@ -437,7 +437,7 @@ _populate()
 ##
 # Map type numbers to type names -- defined in ImageFileDirectory.
 
-TYPES = {}
+TYPES: dict[int, str] = {}
 
 #
 # These tags are handled by default in libtiff, without

src/PIL/_imaging.pyi

@@ -0,0 +1,5 @@
+from __future__ import annotations
+
+from typing import Any
+
+def __getattr__(name: str) -> Any: ...

src/PIL/_tkinter_finder.py

@@ -5,7 +5,8 @@ from __future__ import annotations
 
 import sys
 import tkinter
-from tkinter import _tkinter as tk
+
+tk = getattr(tkinter, "_tkinter")
 
 try:
     if hasattr(sys, "pypy_find_executable"):

src/PIL/_webp.pyi

@@ -0,0 +1,5 @@
+from __future__ import annotations
+
+from typing import Any
+
+def __getattr__(name: str) -> Any: ...

tox.ini

@@ -33,9 +33,14 @@ commands =
 [testenv:mypy]
 skip_install = true
 deps =
+    IceSpringPySideStubs-PyQt6
+    IceSpringPySideStubs-PySide6
     ipython
     mypy==1.7.1
     numpy
+    packaging
+    types-cffi
+    types-defusedxml
 extras =
     typing
 commands =