Pillow/Tests/test_image.py
Jon Dufresne 4cd4adddc3 Improve handling of file resources
Follow Python's file object semantics. User code is responsible for
closing resources (usually through a context manager) in a deterministic
way.

To achieve this, remove __del__ functions. These functions used to
closed open file handlers in an attempt to silence Python
ResourceWarnings. However, using __del__ has the following drawbacks:

- __del__ isn't called until the object's reference count reaches 0.
  Therefore, resource handlers remain open or in use longer than
  necessary.

- The __del__ method isn't guaranteed to execute on system exit. See the
  Python documentation:

  https://docs.python.org/3/reference/datamodel.html#object.__del__

  > It is not guaranteed that __del__() methods are called for objects
  > that still exist when the interpreter exits.

- Exceptions that occur inside __del__ are ignored instead of raised.
  This has the potential of hiding bugs. This is also in the Python
  documentation:

  > Warning: Due to the precarious circumstances under which __del__()
  > methods are invoked, exceptions that occur during their execution
  > are ignored, and a warning is printed to sys.stderr instead.

Instead, always close resource handlers when they are no longer in use.
This will close the file handler at a specified point in the user's code
and not wait until the interpreter chooses to. It is always guaranteed
to run. And, if an exception occurs while closing the file handler, the
bug will not be ignored.

Now, when code receives a ResourceWarning, it will highlight an area
that is mishandling resources. It should not simply be silenced, but
fixed by closing resources with a context manager.

All warnings that were emitted during tests have been cleaned up. To
enable warnings, I passed the `-Wa` CLI option to Python. This exposed
some mishandling of resources in ImageFile.__init__() and
SpiderImagePlugin.loadImageSeries(), they too were fixed.
2019-10-12 08:27:17 -07:00

629 lines
19 KiB
Python

import os
import shutil
import tempfile
from PIL import Image
from PIL._util import py3
from .helper import PillowTestCase, hopper, is_win32, unittest
class TestImage(PillowTestCase):
def test_image_modes_success(self):
for mode in [
"1",
"P",
"PA",
"L",
"LA",
"La",
"F",
"I",
"I;16",
"I;16L",
"I;16B",
"I;16N",
"RGB",
"RGBX",
"RGBA",
"RGBa",
"CMYK",
"YCbCr",
"LAB",
"HSV",
]:
Image.new(mode, (1, 1))
def test_image_modes_fail(self):
for mode in [
"",
"bad",
"very very long",
"BGR;15",
"BGR;16",
"BGR;24",
"BGR;32",
]:
with self.assertRaises(ValueError) as e:
Image.new(mode, (1, 1))
self.assertEqual(str(e.exception), "unrecognized image mode")
def test_sanity(self):
im = Image.new("L", (100, 100))
self.assertEqual(repr(im)[:45], "<PIL.Image.Image image mode=L size=100x100 at")
self.assertEqual(im.mode, "L")
self.assertEqual(im.size, (100, 100))
im = Image.new("RGB", (100, 100))
self.assertEqual(repr(im)[:45], "<PIL.Image.Image image mode=RGB size=100x100 ")
self.assertEqual(im.mode, "RGB")
self.assertEqual(im.size, (100, 100))
Image.new("L", (100, 100), None)
im2 = Image.new("L", (100, 100), 0)
im3 = Image.new("L", (100, 100), "black")
self.assertEqual(im2.getcolors(), [(10000, 0)])
self.assertEqual(im3.getcolors(), [(10000, 0)])
self.assertRaises(ValueError, Image.new, "X", (100, 100))
self.assertRaises(ValueError, Image.new, "", (100, 100))
# self.assertRaises(MemoryError, Image.new, "L", (1000000, 1000000))
def test_width_height(self):
im = Image.new("RGB", (1, 2))
self.assertEqual(im.width, 1)
self.assertEqual(im.height, 2)
with self.assertRaises(AttributeError):
im.size = (3, 4)
def test_invalid_image(self):
if py3:
import io
im = io.BytesIO(b"")
else:
import StringIO
im = StringIO.StringIO("")
self.assertRaises(IOError, Image.open, im)
def test_bad_mode(self):
self.assertRaises(ValueError, Image.open, "filename", "bad mode")
@unittest.skipUnless(Image.HAS_PATHLIB, "requires pathlib/pathlib2")
def test_pathlib(self):
from PIL.Image import Path
with Image.open(Path("Tests/images/multipage-mmap.tiff")) as im:
self.assertEqual(im.mode, "P")
self.assertEqual(im.size, (10, 10))
im = Image.open(Path("Tests/images/hopper.jpg"))
self.assertEqual(im.mode, "RGB")
self.assertEqual(im.size, (128, 128))
temp_file = self.tempfile("temp.jpg")
if os.path.exists(temp_file):
os.remove(temp_file)
im.save(Path(temp_file))
def test_fp_name(self):
temp_file = self.tempfile("temp.jpg")
class FP(object):
def write(a, b):
pass
fp = FP()
fp.name = temp_file
im = hopper()
im.save(fp)
def test_tempfile(self):
# see #1460, pathlib support breaks tempfile.TemporaryFile on py27
# Will error out on save on 3.0.0
im = hopper()
with tempfile.TemporaryFile() as fp:
im.save(fp, "JPEG")
fp.seek(0)
reloaded = Image.open(fp)
self.assert_image_similar(im, reloaded, 20)
def test_unknown_extension(self):
im = hopper()
temp_file = self.tempfile("temp.unknown")
self.assertRaises(ValueError, im.save, temp_file)
def test_internals(self):
im = Image.new("L", (100, 100))
im.readonly = 1
im._copy()
self.assertFalse(im.readonly)
im.readonly = 1
im.paste(0, (0, 0, 100, 100))
self.assertFalse(im.readonly)
@unittest.skipIf(is_win32(), "Test requires opening tempfile twice")
def test_readonly_save(self):
temp_file = self.tempfile("temp.bmp")
shutil.copy("Tests/images/rgb32bf-rgba.bmp", temp_file)
im = Image.open(temp_file)
self.assertTrue(im.readonly)
im.save(temp_file)
def test_dump(self):
im = Image.new("L", (10, 10))
im._dump(self.tempfile("temp_L.ppm"))
im = Image.new("RGB", (10, 10))
im._dump(self.tempfile("temp_RGB.ppm"))
im = Image.new("HSV", (10, 10))
self.assertRaises(ValueError, im._dump, self.tempfile("temp_HSV.ppm"))
def test_comparison_with_other_type(self):
# Arrange
item = Image.new("RGB", (25, 25), "#000")
num = 12
# Act/Assert
# Shouldn't cause AttributeError (#774)
self.assertFalse(item is None)
self.assertFalse(item == num)
def test_expand_x(self):
# Arrange
im = hopper()
orig_size = im.size
xmargin = 5
# Act
im = im._expand(xmargin)
# Assert
self.assertEqual(im.size[0], orig_size[0] + 2 * xmargin)
self.assertEqual(im.size[1], orig_size[1] + 2 * xmargin)
def test_expand_xy(self):
# Arrange
im = hopper()
orig_size = im.size
xmargin = 5
ymargin = 3
# Act
im = im._expand(xmargin, ymargin)
# Assert
self.assertEqual(im.size[0], orig_size[0] + 2 * xmargin)
self.assertEqual(im.size[1], orig_size[1] + 2 * ymargin)
def test_getbands(self):
# Assert
self.assertEqual(hopper("RGB").getbands(), ("R", "G", "B"))
self.assertEqual(hopper("YCbCr").getbands(), ("Y", "Cb", "Cr"))
def test_getchannel_wrong_params(self):
im = hopper()
self.assertRaises(ValueError, im.getchannel, -1)
self.assertRaises(ValueError, im.getchannel, 3)
self.assertRaises(ValueError, im.getchannel, "Z")
self.assertRaises(ValueError, im.getchannel, "1")
def test_getchannel(self):
im = hopper("YCbCr")
Y, Cb, Cr = im.split()
self.assert_image_equal(Y, im.getchannel(0))
self.assert_image_equal(Y, im.getchannel("Y"))
self.assert_image_equal(Cb, im.getchannel(1))
self.assert_image_equal(Cb, im.getchannel("Cb"))
self.assert_image_equal(Cr, im.getchannel(2))
self.assert_image_equal(Cr, im.getchannel("Cr"))
def test_getbbox(self):
# Arrange
im = hopper()
# Act
bbox = im.getbbox()
# Assert
self.assertEqual(bbox, (0, 0, 128, 128))
def test_ne(self):
# Arrange
im1 = Image.new("RGB", (25, 25), "black")
im2 = Image.new("RGB", (25, 25), "white")
# Act / Assert
self.assertNotEqual(im1, im2)
def test_alpha_composite(self):
# https://stackoverflow.com/questions/3374878
# Arrange
from PIL import ImageDraw
expected_colors = sorted(
[
(1122, (128, 127, 0, 255)),
(1089, (0, 255, 0, 255)),
(3300, (255, 0, 0, 255)),
(1156, (170, 85, 0, 192)),
(1122, (0, 255, 0, 128)),
(1122, (255, 0, 0, 128)),
(1089, (0, 255, 0, 0)),
]
)
dst = Image.new("RGBA", size=(100, 100), color=(0, 255, 0, 255))
draw = ImageDraw.Draw(dst)
draw.rectangle((0, 33, 100, 66), fill=(0, 255, 0, 128))
draw.rectangle((0, 67, 100, 100), fill=(0, 255, 0, 0))
src = Image.new("RGBA", size=(100, 100), color=(255, 0, 0, 255))
draw = ImageDraw.Draw(src)
draw.rectangle((33, 0, 66, 100), fill=(255, 0, 0, 128))
draw.rectangle((67, 0, 100, 100), fill=(255, 0, 0, 0))
# Act
img = Image.alpha_composite(dst, src)
# Assert
img_colors = sorted(img.getcolors())
self.assertEqual(img_colors, expected_colors)
def test_alpha_inplace(self):
src = Image.new("RGBA", (128, 128), "blue")
over = Image.new("RGBA", (128, 128), "red")
mask = hopper("L")
over.putalpha(mask)
target = Image.alpha_composite(src, over)
# basic
full = src.copy()
full.alpha_composite(over)
self.assert_image_equal(full, target)
# with offset down to right
offset = src.copy()
offset.alpha_composite(over, (64, 64))
self.assert_image_equal(
offset.crop((64, 64, 127, 127)), target.crop((0, 0, 63, 63))
)
self.assertEqual(offset.size, (128, 128))
# offset and crop
box = src.copy()
box.alpha_composite(over, (64, 64), (0, 0, 32, 32))
self.assert_image_equal(box.crop((64, 64, 96, 96)), target.crop((0, 0, 32, 32)))
self.assert_image_equal(box.crop((96, 96, 128, 128)), src.crop((0, 0, 32, 32)))
self.assertEqual(box.size, (128, 128))
# source point
source = src.copy()
source.alpha_composite(over, (32, 32), (32, 32, 96, 96))
self.assert_image_equal(
source.crop((32, 32, 96, 96)), target.crop((32, 32, 96, 96))
)
self.assertEqual(source.size, (128, 128))
# errors
self.assertRaises(ValueError, source.alpha_composite, over, "invalid source")
self.assertRaises(
ValueError, source.alpha_composite, over, (0, 0), "invalid destination"
)
self.assertRaises(ValueError, source.alpha_composite, over, 0)
self.assertRaises(ValueError, source.alpha_composite, over, (0, 0), 0)
self.assertRaises(ValueError, source.alpha_composite, over, (0, -1))
self.assertRaises(ValueError, source.alpha_composite, over, (0, 0), (0, -1))
def test_registered_extensions_uninitialized(self):
# Arrange
Image._initialized = 0
extension = Image.EXTENSION
Image.EXTENSION = {}
# Act
Image.registered_extensions()
# Assert
self.assertEqual(Image._initialized, 2)
# Restore the original state and assert
Image.EXTENSION = extension
self.assertTrue(Image.EXTENSION)
def test_registered_extensions(self):
# Arrange
# Open an image to trigger plugin registration
with Image.open("Tests/images/rgb.jpg"):
pass
# Act
extensions = Image.registered_extensions()
# Assert
self.assertTrue(extensions)
for ext in [".cur", ".icns", ".tif", ".tiff"]:
self.assertIn(ext, extensions)
def test_effect_mandelbrot(self):
# Arrange
size = (512, 512)
extent = (-3, -2.5, 2, 2.5)
quality = 100
# Act
im = Image.effect_mandelbrot(size, extent, quality)
# Assert
self.assertEqual(im.size, (512, 512))
im2 = Image.open("Tests/images/effect_mandelbrot.png")
self.assert_image_equal(im, im2)
def test_effect_mandelbrot_bad_arguments(self):
# Arrange
size = (512, 512)
# Get coordinates the wrong way round:
extent = (+3, +2.5, -2, -2.5)
# Quality < 2:
quality = 1
# Act/Assert
self.assertRaises(ValueError, Image.effect_mandelbrot, size, extent, quality)
def test_effect_noise(self):
# Arrange
size = (100, 100)
sigma = 128
# Act
im = Image.effect_noise(size, sigma)
# Assert
self.assertEqual(im.size, (100, 100))
self.assertEqual(im.mode, "L")
p0 = im.getpixel((0, 0))
p1 = im.getpixel((0, 1))
p2 = im.getpixel((0, 2))
p3 = im.getpixel((0, 3))
p4 = im.getpixel((0, 4))
self.assert_not_all_same([p0, p1, p2, p3, p4])
def test_effect_spread(self):
# Arrange
im = hopper()
distance = 10
# Act
im2 = im.effect_spread(distance)
# Assert
self.assertEqual(im.size, (128, 128))
im3 = Image.open("Tests/images/effect_spread.png")
self.assert_image_similar(im2, im3, 110)
def test_check_size(self):
# Checking that the _check_size function throws value errors
# when we want it to.
with self.assertRaises(ValueError):
Image.new("RGB", 0) # not a tuple
with self.assertRaises(ValueError):
Image.new("RGB", (0,)) # Tuple too short
with self.assertRaises(ValueError):
Image.new("RGB", (-1, -1)) # w,h < 0
# this should pass with 0 sized images, #2259
im = Image.new("L", (0, 0))
self.assertEqual(im.size, (0, 0))
im = Image.new("L", (0, 100))
self.assertEqual(im.size, (0, 100))
im = Image.new("L", (100, 0))
self.assertEqual(im.size, (100, 0))
self.assertTrue(Image.new("RGB", (1, 1)))
# Should pass lists too
i = Image.new("RGB", [1, 1])
self.assertIsInstance(i.size, tuple)
def test_storage_neg(self):
# Storage.c accepted negative values for xsize, ysize. Was
# test_neg_ppm, but the core function for that has been
# removed Calling directly into core to test the error in
# Storage.c, rather than the size check above
with self.assertRaises(ValueError):
Image.core.fill("RGB", (2, -2), (0, 0, 0))
def test_offset_not_implemented(self):
# Arrange
with hopper() as im:
# Act / Assert
self.assertRaises(NotImplementedError, im.offset, None)
def test_fromstring(self):
self.assertRaises(NotImplementedError, Image.fromstring)
def test_linear_gradient_wrong_mode(self):
# Arrange
wrong_mode = "RGB"
# Act / Assert
self.assertRaises(ValueError, Image.linear_gradient, wrong_mode)
def test_linear_gradient(self):
# Arrange
target_file = "Tests/images/linear_gradient.png"
for mode in ["L", "P"]:
# Act
im = Image.linear_gradient(mode)
# Assert
self.assertEqual(im.size, (256, 256))
self.assertEqual(im.mode, mode)
self.assertEqual(im.getpixel((0, 0)), 0)
self.assertEqual(im.getpixel((255, 255)), 255)
target = Image.open(target_file).convert(mode)
self.assert_image_equal(im, target)
def test_radial_gradient_wrong_mode(self):
# Arrange
wrong_mode = "RGB"
# Act / Assert
self.assertRaises(ValueError, Image.radial_gradient, wrong_mode)
def test_radial_gradient(self):
# Arrange
target_file = "Tests/images/radial_gradient.png"
for mode in ["L", "P"]:
# Act
im = Image.radial_gradient(mode)
# Assert
self.assertEqual(im.size, (256, 256))
self.assertEqual(im.mode, mode)
self.assertEqual(im.getpixel((0, 0)), 255)
self.assertEqual(im.getpixel((128, 128)), 0)
target = Image.open(target_file).convert(mode)
self.assert_image_equal(im, target)
def test_register_extensions(self):
test_format = "a"
exts = ["b", "c"]
for ext in exts:
Image.register_extension(test_format, ext)
ext_individual = Image.EXTENSION.copy()
for ext in exts:
del Image.EXTENSION[ext]
Image.register_extensions(test_format, exts)
ext_multiple = Image.EXTENSION.copy()
for ext in exts:
del Image.EXTENSION[ext]
self.assertEqual(ext_individual, ext_multiple)
def test_remap_palette(self):
# Test illegal image mode
with hopper() as im:
self.assertRaises(ValueError, im.remap_palette, None)
def test__new(self):
from PIL import ImagePalette
im = hopper("RGB")
im_p = hopper("P")
blank_p = Image.new("P", (10, 10))
blank_pa = Image.new("PA", (10, 10))
blank_p.palette = None
blank_pa.palette = None
def _make_new(base_image, im, palette_result=None):
new_im = base_image._new(im)
self.assertEqual(new_im.mode, im.mode)
self.assertEqual(new_im.size, im.size)
self.assertEqual(new_im.info, base_image.info)
if palette_result is not None:
self.assertEqual(new_im.palette.tobytes(), palette_result.tobytes())
else:
self.assertIsNone(new_im.palette)
_make_new(im, im_p, im_p.palette)
_make_new(im_p, im, None)
_make_new(im, blank_p, ImagePalette.ImagePalette())
_make_new(im, blank_pa, ImagePalette.ImagePalette())
def test_p_from_rgb_rgba(self):
for mode, color in [
("RGB", "#DDEEFF"),
("RGB", (221, 238, 255)),
("RGBA", (221, 238, 255, 255)),
]:
im = Image.new("P", (100, 100), color)
expected = Image.new(mode, (100, 100), color)
self.assert_image_equal(im.convert(mode), expected)
def test_no_resource_warning_on_save(self):
# https://github.com/python-pillow/Pillow/issues/835
# Arrange
test_file = "Tests/images/hopper.png"
temp_file = self.tempfile("temp.jpg")
# Act/Assert
with Image.open(test_file) as im:
self.assert_warning(None, im.save, temp_file)
def test_load_on_nonexclusive_multiframe(self):
with open("Tests/images/frozenpond.mpo", "rb") as fp:
def act(fp):
im = Image.open(fp)
im.load()
act(fp)
with Image.open(fp) as im:
im.load()
self.assertFalse(fp.closed)
def test_overrun(self):
for file in ["fli_overrun.bin", "sgi_overrun.bin", "pcx_overrun.bin"]:
with Image.open(os.path.join("Tests/images", file)) as im:
try:
im.load()
self.assertFail()
except IOError as e:
self.assertEqual(str(e), "buffer overrun when reading image file")
class MockEncoder(object):
pass
def mock_encode(*args):
encoder = MockEncoder()
encoder.args = args
return encoder
class TestRegistry(PillowTestCase):
def test_encode_registry(self):
Image.register_encoder("MOCK", mock_encode)
self.assertIn("MOCK", Image.ENCODERS)
enc = Image._getencoder("RGB", "MOCK", ("args",), extra=("extra",))
self.assertIsInstance(enc, MockEncoder)
self.assertEqual(enc.args, ("RGB", "args", "extra"))
def test_encode_registry_fail(self):
self.assertRaises(
IOError,
Image._getencoder,
"RGB",
"DoesNotExist",
("args",),
extra=("extra",),
)