Merge pull request #8032 from nulano/type_hints

Added type hints for PixelAccess related methods and others

Author: radarhere

Tests/test_imagegrab.py

@@ -89,6 +89,7 @@ def test_grabclipboard_file(self) -> None:
         p.communicate()
 
         im = ImageGrab.grabclipboard()
+        assert isinstance(im, list)
         assert len(im) == 1
         assert os.path.samefile(im[0], "Tests/images/hopper.gif")
 
@@ -105,6 +106,7 @@ def test_grabclipboard_png(self) -> None:
         p.communicate()
 
         im = ImageGrab.grabclipboard()
+        assert isinstance(im, Image.Image)
         assert_image_equal_tofile(im, "Tests/images/hopper.png")
 
     @pytest.mark.skipif(
@@ -120,6 +122,7 @@ def test_grabclipboard_wl_clipboard(self, ext: str) -> None:
         with open(image_path, "rb") as fp:
             subprocess.call(["wl-copy"], stdin=fp)
         im = ImageGrab.grabclipboard()
+        assert isinstance(im, Image.Image)
         assert_image_equal_tofile(im, image_path)
 
     @pytest.mark.skipif(

docs/reference/ImageDraw.rst

@@ -691,23 +691,7 @@ Methods
     :param hints: An optional list of hints.
     :returns: A (drawing context, drawing resource factory) tuple.
 
-.. py:method:: floodfill(image, xy, value, border=None, thresh=0)
-
-    .. warning:: This method is experimental.
-
-    Fills a bounded region with a given color.
-
-    :param image: Target image.
-    :param xy: Seed position (a 2-item coordinate tuple).
-    :param value: Fill color.
-    :param border: Optional border value.  If given, the region consists of
-        pixels with a color different from the border color.  If not given,
-        the region consists of pixels having the same color as the seed
-        pixel.
-    :param thresh: Optional threshold value which specifies a maximum
-        tolerable difference of a pixel value from the 'background' in
-        order for it to be replaced. Useful for filling regions of non-
-        homogeneous, but similar, colors.
+.. autofunction:: PIL.ImageDraw.floodfill
 
 .. _BCP 47 language code: https://www.w3.org/International/articles/language-tags/
 .. _OpenType docs: https://learn.microsoft.com/en-us/typography/opentype/spec/featurelist

docs/reference/PixelAccess.rst

@@ -44,42 +44,23 @@ Access using negative indexes is also possible. ::
 -----------------------------
 
 .. class:: PixelAccess
+  :canonical: PIL.Image.core.PixelAccess
 
-  .. method:: __setitem__(self, xy, color):
+  .. method:: __getitem__(self, xy: tuple[int, int]) -> float | tuple[int, ...]
 
-        Modifies the pixel at x,y. The color is given as a single
-        numerical value for single band images, and a tuple for
-        multi-band images
-
-        :param xy: The pixel coordinate, given as (x, y).
-        :param color: The pixel value according to its mode. e.g. tuple (r, g, b) for RGB mode)
-
-  .. method:: __getitem__(self, xy):
-
-       Returns the pixel at x,y. The pixel is returned as a single
-        value for single band images or a tuple for multiple band
-        images
+        Returns the pixel at x,y. The pixel is returned as a single
+        value for single band images or a tuple for multi-band images.
 
         :param xy: The pixel coordinate, given as (x, y).
         :returns: a pixel value for single band images, a tuple of
-          pixel values for multiband images.
+                  pixel values for multiband images.
 
-  .. method:: putpixel(self, xy, color):
+  .. method:: __setitem__(self, xy: tuple[int, int], color: float | tuple[int, ...]) -> None
 
         Modifies the pixel at x,y. The color is given as a single
         numerical value for single band images, and a tuple for
-        multi-band images. In addition to this, RGB and RGBA tuples
-        are accepted for P and PA images.
+        multi-band images.
 
         :param xy: The pixel coordinate, given as (x, y).
-        :param color: The pixel value according to its mode. e.g. tuple (r, g, b) for RGB mode)
-
-  .. method:: getpixel(self, xy):
-
-       Returns the pixel at x,y. The pixel is returned as a single
-        value for single band images or a tuple for multiple band
-        images
-
-        :param xy: The pixel coordinate, given as (x, y).
-        :returns: a pixel value for single band images, a tuple of
-          pixel values for multiband images.
+        :param color: The pixel value according to its mode,
+                      e.g. tuple (r, g, b) for RGB mode.

docs/reference/PyAccess.rst

@@ -44,3 +44,4 @@ Access using negative indexes is also possible. ::
 
 .. autoclass:: PIL.PyAccess.PyAccess()
     :members:
+    :special-members: __getitem__, __setitem__

src/PIL/Image.py

@@ -41,7 +41,16 @@
 from collections.abc import Callable, MutableMapping
 from enum import IntEnum
 from types import ModuleType
-from typing import IO, TYPE_CHECKING, Any, Literal, Protocol, Sequence, Tuple, cast
+from typing import (
+    IO,
+    TYPE_CHECKING,
+    Any,
+    Literal,
+    Protocol,
+    Sequence,
+    Tuple,
+    cast,
+)
 
 # VERSION was removed in Pillow 6.0.0.
 # PILLOW_VERSION was removed in Pillow 9.0.0.
@@ -218,7 +227,7 @@ class Quantize(IntEnum):
 # Registries
 
 if TYPE_CHECKING:
-    from . import ImageFile
+    from . import ImageFile, PyAccess
 ID: list[str] = []
 OPEN: dict[
     str,
@@ -871,7 +880,7 @@ def frombytes(
             msg = "cannot decode image data"
             raise ValueError(msg)
 
-    def load(self):
+    def load(self) -> core.PixelAccess | PyAccess.PyAccess | None:
         """
         Allocates storage for the image and loads the pixel data.  In
         normal cases, you don't need to call this method, since the
@@ -884,7 +893,7 @@ def load(self):
         operations. See :ref:`file-handling` for more information.
 
         :returns: An image access object.
-        :rtype: :ref:`PixelAccess` or :py:class:`PIL.PyAccess`
+        :rtype: :py:class:`.PixelAccess` or :py:class:`.PyAccess`
         """
         if self.im is not None and self.palette and self.palette.dirty:
             # realize palette
@@ -913,6 +922,7 @@ def load(self):
                 if self.pyaccess:
                     return self.pyaccess
             return self.im.pixel_access(self.readonly)
+        return None
 
     def verify(self) -> None:
         """
@@ -1102,7 +1112,10 @@ def convert_transparency(
                 del new_im.info["transparency"]
             if trns is not None:
                 try:
-                    new_im.info["transparency"] = new_im.palette.getcolor(trns, new_im)
+                    new_im.info["transparency"] = new_im.palette.getcolor(
+                        cast(Tuple[int, int, int], trns),  # trns was converted to RGB
+                        new_im,
+                    )
                 except Exception:
                     # if we can't make a transparent color, don't leave the old
                     # transparency hanging around to mess us up.
@@ -1152,7 +1165,10 @@ def convert_transparency(
         if trns is not None:
             if new_im.mode == "P":
                 try:
-                    new_im.info["transparency"] = new_im.palette.getcolor(trns, new_im)
+                    new_im.info["transparency"] = new_im.palette.getcolor(
+                        cast(Tuple[int, int, int], trns),  # trns was converted to RGB
+                        new_im,
+                    )
                 except ValueError as e:
                     del new_im.info["transparency"]
                     if str(e) != "cannot allocate more than 256 colors":
@@ -1657,7 +1673,9 @@ def apply_transparency(self) -> None:
 
         del self.info["transparency"]
 
-    def getpixel(self, xy):
+    def getpixel(
+        self, xy: tuple[int, int] | list[int]
+    ) -> float | tuple[int, ...] | None:
         """
         Returns the pixel value at a given position.
 
@@ -1941,15 +1959,14 @@ def point(self, data):
             flatLut = [round(i) for i in flatLut]
         return self._new(self.im.point(flatLut, mode))
 
-    def putalpha(self, alpha):
+    def putalpha(self, alpha: Image | int) -> None:
         """
         Adds or replaces the alpha layer in this image.  If the image
         does not have an alpha layer, it's converted to "LA" or "RGBA".
         The new layer must be either "L" or "1".
 
         :param alpha: The new alpha layer.  This can either be an "L" or "1"
-           image having the same size as this image, or an integer or
-           other color value.
+           image having the same size as this image, or an integer.
         """
 
         self._ensure_mutable()
@@ -1988,6 +2005,7 @@ def putalpha(self, alpha):
                 alpha = alpha.convert("L")
         else:
             # constant alpha
+            alpha = cast(int, alpha)  # see python/typing#1013
             try:
                 self.im.fillband(band, alpha)
             except (AttributeError, ValueError):
@@ -2056,7 +2074,9 @@ def putpalette(self, data, rawmode="RGB") -> None:
         self.palette.mode = "RGBA" if "A" in rawmode else "RGB"
         self.load()  # install new palette
 
-    def putpixel(self, xy, value):
+    def putpixel(
+        self, xy: tuple[int, int], value: float | tuple[int, ...] | list[int]
+    ) -> None:
         """
         Modifies the pixel at the given position. The color is given as
         a single numerical value for single-band images, and a tuple for
@@ -2094,9 +2114,8 @@ def putpixel(self, xy, value):
             if self.mode == "PA":
                 alpha = value[3] if len(value) == 4 else 255
                 value = value[:3]
-            value = self.palette.getcolor(value, self)
-            if self.mode == "PA":
-                value = (value, alpha)
+            palette_index = self.palette.getcolor(value, self)
+            value = (palette_index, alpha) if self.mode == "PA" else palette_index
         return self.im.putpixel(xy, value)
 
     def remap_palette(self, dest_map, source_palette=None):

src/PIL/ImageDraw.py

@@ -1007,7 +1007,9 @@ def floodfill(
     thresh: float = 0,
 ) -> None:
     """
-    (experimental) Fills a bounded region with a given color.
+    .. warning:: This method is experimental.
+
+    Fills a bounded region with a given color.
 
     :param image: Target image.
     :param xy: Seed position (a 2-item coordinate tuple). See
@@ -1025,6 +1027,7 @@ def floodfill(
     # based on an implementation by Eric S. Raymond
     # amended by yo1995 @20180806
     pixel = image.load()
+    assert pixel is not None
     x, y = xy
     try:
         background = pixel[x, y]

src/PIL/ImageGrab.py

@@ -26,7 +26,13 @@
 from . import Image
 
 
-def grab(bbox=None, include_layered_windows=False, all_screens=False, xdisplay=None):
+def grab(
+    bbox: tuple[int, int, int, int] | None = None,
+    include_layered_windows: bool = False,
+    all_screens: bool = False,
+    xdisplay: str | None = None,
+) -> Image.Image:
+    im: Image.Image
     if xdisplay is None:
         if sys.platform == "darwin":
             fh, filepath = tempfile.mkstemp(".png")
@@ -63,14 +69,16 @@ def grab(bbox=None, include_layered_windows=False, all_screens=False, xdisplay=N
                 left, top, right, bottom = bbox
                 im = im.crop((left - x0, top - y0, right - x0, bottom - y0))
             return im
+    # Cast to Optional[str] needed for Windows and macOS.
+    display_name: str | None = xdisplay
     try:
         if not Image.core.HAVE_XCB:
             msg = "Pillow was built without XCB support"
             raise OSError(msg)
-        size, data = Image.core.grabscreen_x11(xdisplay)
+        size, data = Image.core.grabscreen_x11(display_name)
     except OSError:
         if (
-            xdisplay is None
+            display_name is None
             and sys.platform not in ("darwin", "win32")
             and shutil.which("gnome-screenshot")
         ):
@@ -94,7 +102,7 @@ def grab(bbox=None, include_layered_windows=False, all_screens=False, xdisplay=N
         return im
 
 
-def grabclipboard():
+def grabclipboard() -> Image.Image | list[str] | None:
     if sys.platform == "darwin":
         fh, filepath = tempfile.mkstemp(".png")
         os.close(fh)

src/PIL/PyAccess.py

@@ -77,7 +77,11 @@ def __init__(self, img: Image.Image, readonly: bool = False) -> None:
     def _post_init(self) -> None:
         pass
 
-    def __setitem__(self, xy, color):
+    def __setitem__(
+        self,
+        xy: tuple[int, int] | list[int],
+        color: float | tuple[int, ...] | list[int],
+    ) -> None:
         """
         Modifies the pixel at x,y. The color is given as a single
         numerical value for single band images, and a tuple for
@@ -107,13 +111,12 @@ def __setitem__(self, xy, color):
             if self._im.mode == "PA":
                 alpha = color[3] if len(color) == 4 else 255
                 color = color[:3]
-            color = self._palette.getcolor(color, self._img)
-            if self._im.mode == "PA":
-                color = (color, alpha)
+            palette_index = self._palette.getcolor(color, self._img)
+            color = (palette_index, alpha) if self._im.mode == "PA" else palette_index
 
         return self.set_pixel(x, y, color)
 
-    def __getitem__(self, xy: tuple[int, int]) -> float | tuple[int, ...]:
+    def __getitem__(self, xy: tuple[int, int] | list[int]) -> float | tuple[int, ...]:
         """
         Returns the pixel at x,y. The pixel is returned as a single
         value for single band images or a tuple for multiple band
@@ -145,7 +148,9 @@ def check_xy(self, xy: tuple[int, int]) -> tuple[int, int]:
     def get_pixel(self, x: int, y: int) -> float | tuple[int, ...]:
         raise NotImplementedError()
 
-    def set_pixel(self, x: int, y: int, color: float | tuple[int, ...]) -> None:
+    def set_pixel(
+        self, x: int, y: int, color: float | tuple[int, ...] | list[int]
+    ) -> None:
         raise NotImplementedError()
 
 

src/PIL/_imaging.pyi

@@ -10,7 +10,10 @@ class ImagingDraw:
     def __getattr__(self, name: str) -> Any: ...
 
 class PixelAccess:
-    def __getattr__(self, name: str) -> Any: ...
+    def __getitem__(self, xy: tuple[int, int]) -> float | tuple[int, ...]: ...
+    def __setitem__(
+        self, xy: tuple[int, int], color: float | tuple[int, ...]
+    ) -> None: ...
 
 class ImagingDecoder:
     def __getattr__(self, name: str) -> Any: ...