Pillow

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from __future__ import annotations
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import pytest
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from PIL import Image, ImagePalette
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from .helper import assert_image_equal, assert_image_equal_tofile, hopper
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def test_putpalette() -> None:
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    def palette(mode: str) -> str | tuple[str, list[int]]:
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        im = hopper(mode).copy()
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        im.putpalette(list(range(256)) * 3)
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        p = im.getpalette()
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        if p:
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            return im.mode, p[:10]
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        return im.mode
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    with pytest.raises(ValueError):
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        palette("1")
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    for mode in ["L", "LA", "P", "PA"]:
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        assert palette(mode) == (
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            "PA" if "A" in mode else "P",
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            [0, 1, 2, 3, 4, 5, 6, 7, 8, 9],
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        )
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    with pytest.raises(ValueError):
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        palette("I")
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    with pytest.raises(ValueError):
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        palette("F")
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    with pytest.raises(ValueError):
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        palette("RGB")
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    with pytest.raises(ValueError):
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        palette("RGBA")
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    with pytest.raises(ValueError):
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        palette("YCbCr")
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    with Image.open("Tests/images/hopper_gray.jpg") as im:
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        assert im.mode == "L"
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        im.putpalette(list(range(256)) * 3)
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    with Image.open("Tests/images/la.tga") as im:
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        assert im.mode == "LA"
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        im.putpalette(list(range(256)) * 3)
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def test_imagepalette() -> None:
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    im = hopper("P")
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    im.putpalette(ImagePalette.negative())
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    assert_image_equal_tofile(im.convert("RGB"), "Tests/images/palette_negative.png")
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    im.putpalette(ImagePalette.random())
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    im.putpalette(ImagePalette.sepia())
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    assert_image_equal_tofile(im.convert("RGB"), "Tests/images/palette_sepia.png")
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    im.putpalette(ImagePalette.wedge())
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    assert_image_equal_tofile(im.convert("RGB"), "Tests/images/palette_wedge.png")
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def test_putpalette_with_alpha_values() -> None:
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    with Image.open("Tests/images/transparent.gif") as im:
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        expected = im.convert("RGBA")
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        palette = im.getpalette()
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        transparency = im.info.pop("transparency")
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        palette_with_alpha_values = []
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        for i in range(256):
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            color = palette[i * 3 : i * 3 + 3]
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            alpha = 0 if i == transparency else 255
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            palette_with_alpha_values += color + [alpha]
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        im.putpalette(palette_with_alpha_values, "RGBA")
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        assert_image_equal(im.convert("RGBA"), expected)
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@pytest.mark.parametrize(
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    "mode, palette",
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    (
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        ("RGBA", (1, 2, 3, 4)),
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        ("RGBAX", (1, 2, 3, 4, 0)),
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        ("ARGB", (4, 1, 2, 3)),
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    ),
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)
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def test_rgba_palette(mode: str, palette: tuple[int, ...]) -> None:
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    im = Image.new("P", (1, 1))
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    im.putpalette(palette, mode)
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    assert im.getpalette() == [1, 2, 3]
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    assert im.palette is not None
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    assert im.palette.colors == {(1, 2, 3, 4): 0}
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def test_empty_palette() -> None:
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    im = Image.new("P", (1, 1))
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    assert im.getpalette() == []
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def test_undefined_palette_index() -> None:
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    im = Image.new("P", (1, 1), 3)
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    im.putpalette((1, 2, 3))
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    assert im.convert("RGB").getpixel((0, 0)) == (0, 0, 0)
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