Pillow/Tests/test_imagetext.py
2025-12-11 07:51:12 +11:00

231 lines
7.6 KiB
Python

from __future__ import annotations
import pytest
from PIL import Image, ImageDraw, ImageFont, ImageText, features
from .helper import assert_image_similar_tofile, skip_unless_feature
FONT_PATH = "Tests/fonts/FreeMono.ttf"
@pytest.fixture(
scope="module",
params=[
pytest.param(ImageFont.Layout.BASIC),
pytest.param(ImageFont.Layout.RAQM, marks=skip_unless_feature("raqm")),
],
)
def layout_engine(request: pytest.FixtureRequest) -> ImageFont.Layout:
return request.param
@pytest.fixture(
scope="module",
params=[
None,
pytest.param(ImageFont.Layout.BASIC, marks=skip_unless_feature("freetype2")),
pytest.param(ImageFont.Layout.RAQM, marks=skip_unless_feature("raqm")),
],
)
def font(
request: pytest.FixtureRequest,
) -> ImageFont.ImageFont | ImageFont.FreeTypeFont:
layout_engine = request.param
if layout_engine is None:
return ImageFont.load_default_imagefont()
else:
return ImageFont.truetype(FONT_PATH, 20, layout_engine=layout_engine)
def test_get_length(font: ImageFont.ImageFont | ImageFont.FreeTypeFont) -> None:
factor = 1 if isinstance(font, ImageFont.ImageFont) else 2
assert ImageText.Text("A", font).get_length() == 6 * factor
assert ImageText.Text("AB", font).get_length() == 12 * factor
assert ImageText.Text("M", font).get_length() == 6 * factor
assert ImageText.Text("y", font).get_length() == 6 * factor
assert ImageText.Text("a", font).get_length() == 6 * factor
text = ImageText.Text("\n", font)
with pytest.raises(ValueError, match="can't measure length of multiline text"):
text.get_length()
@pytest.mark.parametrize(
"text, expected",
(
("A", (0, 4, 12, 16)),
("AB", (0, 4, 24, 16)),
("M", (0, 4, 12, 16)),
("y", (0, 7, 12, 20)),
("a", (0, 7, 12, 16)),
),
)
def test_get_bbox(
font: ImageFont.ImageFont | ImageFont.FreeTypeFont,
text: str,
expected: tuple[int, int, int, int],
) -> None:
if isinstance(font, ImageFont.ImageFont):
expected = (0, 0, expected[2] // 2, 11)
assert ImageText.Text(text, font).get_bbox() == expected
def test_standard_embedded_color(layout_engine: ImageFont.Layout) -> None:
if features.check_module("freetype2"):
font = ImageFont.truetype(FONT_PATH, 40, layout_engine=layout_engine)
text = ImageText.Text("Hello World!", font)
text.embed_color()
assert text.get_length() == 288
im = Image.new("RGB", (300, 64), "white")
draw = ImageDraw.Draw(im)
draw.text((10, 10), text, "#fa6")
assert_image_similar_tofile(im, "Tests/images/standard_embedded.png", 3.1)
text = ImageText.Text("", mode="1")
with pytest.raises(
ValueError, match="Embedded color supported only in RGB and RGBA modes"
):
text.embed_color()
@skip_unless_feature("freetype2")
def test_stroke() -> None:
for suffix, stroke_fill in {"same": None, "different": "#0f0"}.items():
# Arrange
im = Image.new("RGB", (120, 130))
draw = ImageDraw.Draw(im)
font = ImageFont.truetype(FONT_PATH, 120)
text = ImageText.Text("A", font)
text.stroke(2, stroke_fill)
# Act
draw.text((12, 12), text, "#f00")
# Assert
assert_image_similar_tofile(
im, "Tests/images/imagedraw_stroke_" + suffix + ".png", 3.1
)
@pytest.mark.parametrize(
"data, width, expected",
(
("Hello World!", 100, "Hello World!"), # No wrap required
("Hello World!", 50, "Hello\nWorld!"), # Wrap word to a new line
# Keep multiple spaces within a line
("Keep multiple spaces", 90, "Keep multiple\nspaces"),
(" Keep\n leading space", 100, " Keep\n leading space"),
),
)
@pytest.mark.parametrize("string", (True, False))
def test_wrap(data: str, width: int, expected: str, string: bool) -> None:
if string:
text = ImageText.Text(data)
assert text.wrap(width) is None
assert text.text == expected
else:
text_bytes = ImageText.Text(data.encode())
assert text_bytes.wrap(width) is None
assert text_bytes.text == expected.encode()
def test_wrap_long_word() -> None:
text = ImageText.Text("Hello World!")
with pytest.raises(ValueError, match="Word does not fit within line"):
text.wrap(25)
def test_wrap_unsupported(font: ImageFont.FreeTypeFont) -> None:
transposed_font = ImageFont.TransposedFont(font)
text = ImageText.Text("Hello World!", transposed_font)
with pytest.raises(ValueError, match="TransposedFont not supported"):
text.wrap(50)
text = ImageText.Text("Hello World!", direction="ttb")
with pytest.raises(ValueError, match="Only ltr direction supported"):
text.wrap(50)
def test_wrap_height() -> None:
width = 50 if features.check_module("freetype2") else 60
text = ImageText.Text("Text does not fit within height")
wrapped = text.wrap(width, 25 if features.check_module("freetype2") else 40)
assert wrapped is not None
assert wrapped.text == " within height"
assert text.text == "Text does\nnot fit"
text = ImageText.Text("Text does not fit\nwithin height")
wrapped = text.wrap(width, 20)
assert wrapped is not None
assert wrapped.text == " not fit\nwithin height"
assert text.text == "Text does"
text = ImageText.Text("Text does not fit\n\nwithin height")
wrapped = text.wrap(width, 25 if features.check_module("freetype2") else 40)
assert wrapped is not None
assert wrapped.text == "\nwithin height"
assert text.text == "Text does\nnot fit"
def test_wrap_scaling_unsupported() -> None:
font = ImageFont.load_default_imagefont()
text = ImageText.Text("Hello World!", font)
with pytest.raises(ValueError, match="'scaling' only supports FreeTypeFont"):
text.wrap(50, scaling="shrink")
if features.check_module("freetype2"):
text = ImageText.Text("Hello World!")
with pytest.raises(ValueError, match="'scaling' requires 'height'"):
text.wrap(50, scaling="shrink")
@skip_unless_feature("freetype2")
def test_wrap_shrink() -> None:
# No scaling required
text = ImageText.Text("Hello World!")
assert isinstance(text.font, ImageFont.FreeTypeFont)
assert text.font.size == 10
assert text.wrap(50, 50, "shrink") is None
assert isinstance(text.font, ImageFont.FreeTypeFont)
assert text.font.size == 10
with pytest.raises(ValueError, match="Text could not be scaled"):
text.wrap(50, 15, ("shrink", 9))
assert text.wrap(50, 15, "shrink") is None
assert text.font.size == 8
text = ImageText.Text("Hello World!")
assert text.wrap(50, 15, ("shrink", 7)) is None
assert isinstance(text.font, ImageFont.FreeTypeFont)
assert text.font.size == 8
@skip_unless_feature("freetype2")
def test_wrap_grow() -> None:
# No scaling required
text = ImageText.Text("Hello World!")
assert isinstance(text.font, ImageFont.FreeTypeFont)
assert text.font.size == 10
assert text.wrap(58, 10, "grow") is None
assert isinstance(text.font, ImageFont.FreeTypeFont)
assert text.font.size == 10
with pytest.raises(ValueError, match="Text could not be scaled"):
text.wrap(50, 50, ("grow", 12))
assert text.wrap(50, 50, "grow") is None
assert text.font.size == 16
text = ImageText.Text("A\nB")
with pytest.raises(ValueError, match="Text could not be scaled"):
text.wrap(50, 10, "grow")
text = ImageText.Text("Hello World!")
assert text.wrap(50, 50, ("grow", 18)) is None
assert isinstance(text.font, ImageFont.FreeTypeFont)
assert text.font.size == 16