Added type hints

src/PIL/BlpImagePlugin.py

@@ -61,17 +61,19 @@ def unpack_565(i: int) -> tuple[int, int, int]:
     return ((i >> 11) & 0x1F) << 3, ((i >> 5) & 0x3F) << 2, (i & 0x1F) << 3
 
 
-def decode_dxt1(data, alpha=False):
+def decode_dxt1(
+    data: bytes, alpha: bool = False
+) -> tuple[bytearray, bytearray, bytearray, bytearray]:
     """
     input: one "row" of data (i.e. will produce 4*width pixels)
     """
 
     blocks = len(data) // 8  # number of blocks in row
     ret = (bytearray(), bytearray(), bytearray(), bytearray())
 
-    for block in range(blocks):
+    for block_index in range(blocks):
         # Decode next 8-byte block.
-        idx = block * 8
+        idx = block_index * 8
         color0, color1, bits = struct.unpack_from("<HHI", data, idx)
 
         r0, g0, b0 = unpack_565(color0)
@@ -116,16 +118,16 @@ def decode_dxt1(data, alpha=False):
     return ret
 
 
-def decode_dxt3(data):
+def decode_dxt3(data: bytes) -> tuple[bytearray, bytearray, bytearray, bytearray]:
     """
     input: one "row" of data (i.e. will produce 4*width pixels)
     """
 
     blocks = len(data) // 16  # number of blocks in row
     ret = (bytearray(), bytearray(), bytearray(), bytearray())
 
-    for block in range(blocks):
-        idx = block * 16
+    for block_index in range(blocks):
+        idx = block_index * 16
         block = data[idx : idx + 16]
         # Decode next 16-byte block.
         bits = struct.unpack_from("<8B", block)
@@ -169,16 +171,16 @@ def decode_dxt3(data):
     return ret
 
 
-def decode_dxt5(data):
+def decode_dxt5(data: bytes) -> tuple[bytearray, bytearray, bytearray, bytearray]:
     """
     input: one "row" of data (i.e. will produce 4 * width pixels)
     """
 
     blocks = len(data) // 16  # number of blocks in row
     ret = (bytearray(), bytearray(), bytearray(), bytearray())
 
-    for block in range(blocks):
-        idx = block * 16
+    for block_index in range(blocks):
+        idx = block_index * 16
         block = data[idx : idx + 16]
         # Decode next 16-byte block.
         a0, a1 = struct.unpack_from("<BB", block)

src/PIL/BmpImagePlugin.py

@@ -301,7 +301,8 @@ def _open(self) -> None:
 class BmpRleDecoder(ImageFile.PyDecoder):
     _pulls_fd = True
 
-    def decode(self, buffer):
+    def decode(self, buffer: bytes) -> tuple[int, int]:
+        assert self.fd is not None
         rle4 = self.args[1]
         data = bytearray()
         x = 0

src/PIL/DdsImagePlugin.py

@@ -480,7 +480,8 @@ def load_seek(self, pos: int) -> None:
 class DdsRgbDecoder(ImageFile.PyDecoder):
     _pulls_fd = True
 
-    def decode(self, buffer):
+    def decode(self, buffer: bytes) -> tuple[int, int]:
+        assert self.fd is not None
         bitcount, masks = self.args
 
         # Some masks will be padded with zeros, e.g. R 0b11 G 0b1100

src/PIL/EpsImagePlugin.py

@@ -27,6 +27,7 @@
 import subprocess
 import sys
 import tempfile
+from typing import IO
 
 from . import Image, ImageFile
 from ._binary import i32le as i32
@@ -236,35 +237,33 @@ def check_required_header_comments() -> None:
                 msg = 'EPS header missing "%%BoundingBox" comment'
                 raise SyntaxError(msg)
 
-        def _read_comment(s):
+        def _read_comment(s: str) -> bool:
             nonlocal reading_trailer_comments
             try:
                 m = split.match(s)
             except re.error as e:
                 msg = "not an EPS file"
                 raise SyntaxError(msg) from e
 
-            if m:
-                k, v = m.group(1, 2)
-                self.info[k] = v
-                if k == "BoundingBox":
-                    if v == "(atend)":
-                        reading_trailer_comments = True
-                    elif not self._size or (
-                        trailer_reached and reading_trailer_comments
-                    ):
-                        try:
-                            # Note: The DSC spec says that BoundingBox
-                            # fields should be integers, but some drivers
-                            # put floating point values there anyway.
-                            box = [int(float(i)) for i in v.split()]
-                            self._size = box[2] - box[0], box[3] - box[1]
-                            self.tile = [
-                                ("eps", (0, 0) + self.size, offset, (length, box))
-                            ]
-                        except Exception:
-                            pass
-                return True
+            if not m:
+                return False
+
+            k, v = m.group(1, 2)
+            self.info[k] = v
+            if k == "BoundingBox":
+                if v == "(atend)":
+                    reading_trailer_comments = True
+                elif not self._size or (trailer_reached and reading_trailer_comments):
+                    try:
+                        # Note: The DSC spec says that BoundingBox
+                        # fields should be integers, but some drivers
+                        # put floating point values there anyway.
+                        box = [int(float(i)) for i in v.split()]
+                        self._size = box[2] - box[0], box[3] - box[1]
+                        self.tile = [("eps", (0, 0) + self.size, offset, (length, box))]
+                    except Exception:
+                        pass
+            return True
 
         while True:
             byte = self.fp.read(1)
@@ -413,7 +412,7 @@ def load_seek(self, pos: int) -> None:
 # --------------------------------------------------------------------
 
 
-def _save(im, fp, filename, eps=1):
+def _save(im: Image.Image, fp: IO[bytes], filename: str | bytes, eps: int = 1) -> None:
     """EPS Writer for the Python Imaging Library."""
 
     # make sure image data is available

src/PIL/FitsImagePlugin.py

@@ -122,7 +122,7 @@ def _parse_headers(
 class FitsGzipDecoder(ImageFile.PyDecoder):
     _pulls_fd = True
 
-    def decode(self, buffer):
+    def decode(self, buffer: bytes) -> tuple[int, int]:
         assert self.fd is not None
         value = gzip.decompress(self.fd.read())
 

src/PIL/FpxImagePlugin.py

@@ -241,7 +241,7 @@ def close(self) -> None:
         self.ole.close()
         super().close()
 
-    def __exit__(self, *args):
+    def __exit__(self, *args: object) -> None:
         self.ole.close()
         super().__exit__()
 

src/PIL/ImageFile.py

@@ -487,7 +487,7 @@ def feed(self, data):
     def __enter__(self):
         return self
 
-    def __exit__(self, *args):
+    def __exit__(self, *args: object) -> None:
         self.close()
 
     def close(self):

src/PIL/Jpeg2KImagePlugin.py

@@ -18,7 +18,7 @@
 import io
 import os
 import struct
-from typing import IO
+from typing import IO, Tuple, cast
 
 from . import Image, ImageFile, ImagePalette, _binary
 
@@ -59,7 +59,7 @@ def _read_bytes(self, num_bytes: int) -> bytes:
             self.remaining_in_box -= num_bytes
         return data
 
-    def read_fields(self, field_format):
+    def read_fields(self, field_format: str) -> tuple[int | bytes, ...]:
         size = struct.calcsize(field_format)
         data = self._read_bytes(size)
         return struct.unpack(field_format, data)
@@ -82,9 +82,9 @@ def next_box_type(self) -> bytes:
         self.remaining_in_box = -1
 
         # Read the length and type of the next box
-        lbox, tbox = self.read_fields(">I4s")
+        lbox, tbox = cast(Tuple[int, bytes], self.read_fields(">I4s"))
         if lbox == 1:
-            lbox = self.read_fields(">Q")[0]
+            lbox = cast(int, self.read_fields(">Q")[0])
             hlen = 16
         else:
             hlen = 8
@@ -127,12 +127,13 @@ def _parse_codestream(fp):
     return size, mode
 
 
-def _res_to_dpi(num, denom, exp):
+def _res_to_dpi(num: int, denom: int, exp: int) -> float | None:
     """Convert JPEG2000's (numerator, denominator, exponent-base-10) resolution,
     calculated as (num / denom) * 10^exp and stored in dots per meter,
     to floating-point dots per inch."""
-    if denom != 0:
-        return (254 * num * (10**exp)) / (10000 * denom)
+    if denom == 0:
+        return None
+    return (254 * num * (10**exp)) / (10000 * denom)
 
 
 def _parse_jp2_header(fp):

src/PIL/MicImagePlugin.py

@@ -93,7 +93,7 @@ def close(self) -> None:
         self.ole.close()
         super().close()
 
-    def __exit__(self, *args):
+    def __exit__(self, *args: object) -> None:
         self.__fp.close()
         self.ole.close()
         super().__exit__()

src/PIL/MpoImagePlugin.py

@@ -37,19 +37,14 @@ def _save(im: Image.Image, fp: IO[bytes], filename: str | bytes) -> None:
     JpegImagePlugin._save(im, fp, filename)
 
 
-def _save_all(im, fp, filename):
+def _save_all(im: Image.Image, fp: IO[bytes], filename: str | bytes) -> None:
     append_images = im.encoderinfo.get("append_images", [])
-    if not append_images:
-        try:
-            animated = im.is_animated
-        except AttributeError:
-            animated = False
-        if not animated:
-            _save(im, fp, filename)
-            return
+    if not append_images and not getattr(im, "is_animated", False):
+        _save(im, fp, filename)
+        return
 
     mpf_offset = 28
-    offsets = []
+    offsets: list[int] = []
     for imSequence in itertools.chain([im], append_images):
         for im_frame in ImageSequence.Iterator(imSequence):
             if not offsets:

src/PIL/PSDraw.py

@@ -138,7 +138,7 @@ def image(
             sx = x / im.size[0]
             sy = y / im.size[1]
             self.fp.write(b"%f %f scale\n" % (sx, sy))
-        EpsImagePlugin._save(im, self.fp, None, 0)
+        EpsImagePlugin._save(im, self.fp, "", 0)
         self.fp.write(b"\ngrestore\n")
 
 

src/PIL/PalmImagePlugin.py

@@ -8,6 +8,8 @@
 ##
 from __future__ import annotations
 
+from typing import IO
+
 from . import Image, ImageFile
 from ._binary import o8
 from ._binary import o16be as o16b
@@ -82,10 +84,10 @@
 
 
 # so build a prototype image to be used for palette resampling
-def build_prototype_image():
+def build_prototype_image() -> Image.Image:
     image = Image.new("L", (1, len(_Palm8BitColormapValues)))
     image.putdata(list(range(len(_Palm8BitColormapValues))))
-    palettedata = ()
+    palettedata: tuple[int, ...] = ()
     for colormapValue in _Palm8BitColormapValues:
         palettedata += colormapValue
     palettedata += (0, 0, 0) * (256 - len(_Palm8BitColormapValues))
@@ -112,7 +114,7 @@ def build_prototype_image():
 # (Internal) Image save plugin for the Palm format.
 
 
-def _save(im, fp, filename):
+def _save(im: Image.Image, fp: IO[bytes], filename: str | bytes) -> None:
     if im.mode == "P":
         # we assume this is a color Palm image with the standard colormap,
         # unless the "info" dict has a "custom-colormap" field
@@ -141,7 +143,7 @@ def _save(im, fp, filename):
             raise OSError(msg)
 
         # we ignore the palette here
-        im.mode = "P"
+        im._mode = "P"
         rawmode = f"P;{bpp}"
         version = 1
 

src/PIL/PdfParser.py

@@ -404,9 +404,8 @@ def __init__(self, filename=None, f=None, buf=None, start_offset=0, mode="rb"):
     def __enter__(self) -> PdfParser:
         return self
 
-    def __exit__(self, exc_type, exc_value, traceback):
+    def __exit__(self, *args: object) -> None:
         self.close()
-        return False  # do not suppress exceptions
 
     def start_writing(self) -> None:
         self.close_buf()

src/PIL/PngImagePlugin.py

@@ -178,7 +178,7 @@ def read(self) -> tuple[bytes, int, int]:
     def __enter__(self) -> ChunkStream:
         return self
 
-    def __exit__(self, *args):
+    def __exit__(self, *args: object) -> None:
         self.close()
 
     def close(self) -> None:

src/PIL/TarIO.py

@@ -16,7 +16,6 @@
 from __future__ import annotations
 
 import io
-from types import TracebackType
 
 from . import ContainerIO
 
@@ -61,12 +60,7 @@ def __init__(self, tarfile: str, file: str) -> None:
     def __enter__(self) -> TarIO:
         return self
 
-    def __exit__(
-        self,
-        exc_type: type[BaseException] | None,
-        exc_val: BaseException | None,
-        exc_tb: TracebackType | None,
-    ) -> None:
+    def __exit__(self, *args: object) -> None:
         self.close()
 
     def close(self) -> None: