Pillow/Tests/helper.py
2019-10-08 12:56:43 +01:00

398 lines
12 KiB
Python

"""
Helper functions.
"""
from __future__ import print_function
import logging
import os
import subprocess
import sys
import tempfile
import unittest
from io import BytesIO
from PIL import Image, ImageMath
from PIL._util import py3
logger = logging.getLogger(__name__)
HAS_UPLOADER = False
if os.environ.get("SHOW_ERRORS", None):
# local img.show for errors.
HAS_UPLOADER = True
class test_image_results:
@classmethod
def upload(self, a, b):
a.show()
b.show()
else:
try:
import test_image_results
HAS_UPLOADER = True
except ImportError:
pass
def convert_to_comparable(a, b):
new_a, new_b = a, b
if a.mode == "P":
new_a = Image.new("L", a.size)
new_b = Image.new("L", b.size)
new_a.putdata(a.getdata())
new_b.putdata(b.getdata())
elif a.mode == "I;16":
new_a = a.convert("I")
new_b = b.convert("I")
return new_a, new_b
class PillowTestCase(unittest.TestCase):
def __init__(self, *args, **kwargs):
unittest.TestCase.__init__(self, *args, **kwargs)
# holds last result object passed to run method:
self.currentResult = None
def run(self, result=None):
self.currentResult = result # remember result for use later
unittest.TestCase.run(self, result) # call superclass run method
def delete_tempfile(self, path):
try:
ok = self.currentResult.wasSuccessful()
except AttributeError: # for pytest
ok = True
if ok:
# only clean out tempfiles if test passed
try:
os.remove(path)
except OSError:
pass # report?
else:
print("=== orphaned temp file: %s" % path)
def assert_deep_equal(self, a, b, msg=None):
try:
self.assertEqual(
len(a), len(b), msg or "got length %s, expected %s" % (len(a), len(b))
)
self.assertTrue(
all(x == y for x, y in zip(a, b)), msg or "got %s, expected %s" % (a, b)
)
except Exception:
self.assertEqual(a, b, msg)
def assert_image(self, im, mode, size, msg=None):
if mode is not None:
self.assertEqual(
im.mode, mode, msg or "got mode %r, expected %r" % (im.mode, mode)
)
if size is not None:
self.assertEqual(
im.size, size, msg or "got size %r, expected %r" % (im.size, size)
)
def assert_image_equal(self, a, b, msg=None):
self.assertEqual(
a.mode, b.mode, msg or "got mode %r, expected %r" % (a.mode, b.mode)
)
self.assertEqual(
a.size, b.size, msg or "got size %r, expected %r" % (a.size, b.size)
)
if a.tobytes() != b.tobytes():
if HAS_UPLOADER:
try:
url = test_image_results.upload(a, b)
logger.error("Url for test images: %s" % url)
except Exception:
pass
self.fail(msg or "got different content")
def assert_image_equal_tofile(self, a, filename, msg=None, mode=None):
with Image.open(filename) as img:
if mode:
img = img.convert(mode)
self.assert_image_equal(a, img, msg)
def assert_image_similar(self, a, b, epsilon, msg=None):
epsilon = float(epsilon)
self.assertEqual(
a.mode, b.mode, msg or "got mode %r, expected %r" % (a.mode, b.mode)
)
self.assertEqual(
a.size, b.size, msg or "got size %r, expected %r" % (a.size, b.size)
)
a, b = convert_to_comparable(a, b)
diff = 0
for ach, bch in zip(a.split(), b.split()):
chdiff = ImageMath.eval("abs(a - b)", a=ach, b=bch).convert("L")
diff += sum(i * num for i, num in enumerate(chdiff.histogram()))
ave_diff = float(diff) / (a.size[0] * a.size[1])
try:
self.assertGreaterEqual(
epsilon,
ave_diff,
(msg or "")
+ " average pixel value difference %.4f > epsilon %.4f"
% (ave_diff, epsilon),
)
except Exception as e:
if HAS_UPLOADER:
try:
url = test_image_results.upload(a, b)
logger.error("Url for test images: %s" % url)
except Exception:
pass
raise e
def assert_image_similar_tofile(self, a, filename, epsilon, msg=None, mode=None):
with Image.open(filename) as img:
if mode:
img = img.convert(mode)
self.assert_image_similar(a, img, epsilon, msg)
def assert_warning(self, warn_class, func, *args, **kwargs):
import warnings
with warnings.catch_warnings(record=True) as w:
# Cause all warnings to always be triggered.
warnings.simplefilter("always")
# Hopefully trigger a warning.
result = func(*args, **kwargs)
# Verify some things.
if warn_class is None:
self.assertEqual(
len(w), 0, "Expected no warnings, got %s" % [v.category for v in w]
)
else:
self.assertGreaterEqual(len(w), 1)
found = False
for v in w:
if issubclass(v.category, warn_class):
found = True
break
self.assertTrue(found)
return result
def assert_all_same(self, items, msg=None):
self.assertEqual(items.count(items[0]), len(items), msg)
def assert_not_all_same(self, items, msg=None):
self.assertNotEqual(items.count(items[0]), len(items), msg)
def assert_tuple_approx_equal(self, actuals, targets, threshold, msg):
"""Tests if actuals has values within threshold from targets"""
value = True
for i, target in enumerate(targets):
value *= target - threshold <= actuals[i] <= target + threshold
self.assertTrue(value, msg + ": " + repr(actuals) + " != " + repr(targets))
def skipKnownBadTest(self, msg=None, platform=None, travis=None, interpreter=None):
# Skip if platform/travis matches, and
# PILLOW_RUN_KNOWN_BAD is not true in the environment.
if os.environ.get("PILLOW_RUN_KNOWN_BAD", False):
print(os.environ.get("PILLOW_RUN_KNOWN_BAD", False))
return
skip = True
if platform is not None:
skip = sys.platform.startswith(platform)
if travis is not None:
skip = skip and (travis == bool(os.environ.get("TRAVIS", False)))
if interpreter is not None:
skip = skip and (
interpreter == "pypy" and hasattr(sys, "pypy_version_info")
)
if skip:
self.skipTest(msg or "Known Bad Test")
def tempfile(self, template):
assert template[:5] in ("temp.", "temp_")
fd, path = tempfile.mkstemp(template[4:], template[:4])
os.close(fd)
self.addCleanup(self.delete_tempfile, path)
return path
def open_withImagemagick(self, f):
if not imagemagick_available():
raise IOError()
outfile = self.tempfile("temp.png")
if command_succeeds([IMCONVERT, f, outfile]):
return Image.open(outfile)
raise IOError()
@unittest.skipIf(sys.platform.startswith("win32"), "requires Unix or macOS")
class PillowLeakTestCase(PillowTestCase):
# requires unix/macOS
iterations = 100 # count
mem_limit = 512 # k
def _get_mem_usage(self):
"""
Gets the RUSAGE memory usage, returns in K. Encapsulates the difference
between macOS and Linux rss reporting
:returns: memory usage in kilobytes
"""
from resource import getrusage, RUSAGE_SELF
mem = getrusage(RUSAGE_SELF).ru_maxrss
if sys.platform == "darwin":
# man 2 getrusage:
# ru_maxrss
# This is the maximum resident set size utilized (in bytes).
return mem / 1024 # Kb
else:
# linux
# man 2 getrusage
# ru_maxrss (since Linux 2.6.32)
# This is the maximum resident set size used (in kilobytes).
return mem # Kb
def _test_leak(self, core):
start_mem = self._get_mem_usage()
for cycle in range(self.iterations):
core()
mem = self._get_mem_usage() - start_mem
msg = "memory usage limit exceeded in iteration %d" % cycle
self.assertLess(mem, self.mem_limit, msg)
# helpers
if not py3:
# Remove DeprecationWarning in Python 3
PillowTestCase.assertRaisesRegex = PillowTestCase.assertRaisesRegexp
PillowTestCase.assertRegex = PillowTestCase.assertRegexpMatches
def fromstring(data):
return Image.open(BytesIO(data))
def tostring(im, string_format, **options):
out = BytesIO()
im.save(out, string_format, **options)
return out.getvalue()
def hopper(mode=None, cache={}):
if mode is None:
# Always return fresh not-yet-loaded version of image.
# Operations on not-yet-loaded images is separate class of errors
# what we should catch.
return Image.open("Tests/images/hopper.ppm")
# Use caching to reduce reading from disk but so an original copy is
# returned each time and the cached image isn't modified by tests
# (for fast, isolated, repeatable tests).
im = cache.get(mode)
if im is None:
if mode == "F":
im = hopper("L").convert(mode)
elif mode[:4] == "I;16":
im = hopper("I").convert(mode)
else:
im = hopper().convert(mode)
cache[mode] = im
return im.copy()
def command_succeeds(cmd):
"""
Runs the command, which must be a list of strings. Returns True if the
command succeeds, or False if an OSError was raised by subprocess.Popen.
"""
with open(os.devnull, "wb") as f:
try:
subprocess.call(cmd, stdout=f, stderr=subprocess.STDOUT)
except OSError:
return False
return True
def djpeg_available():
return command_succeeds(["djpeg", "-version"])
def cjpeg_available():
return command_succeeds(["cjpeg", "-version"])
def netpbm_available():
return command_succeeds(["ppmquant", "--version"]) and command_succeeds(
["ppmtogif", "--version"]
)
def imagemagick_available():
return IMCONVERT and command_succeeds([IMCONVERT, "-version"])
def on_appveyor():
return "APPVEYOR" in os.environ
def on_github_actions():
return "GITHUB_ACTIONS" in os.environ
def on_ci():
# Travis and AppVeyor have "CI"
# Azure Pipelines has "TF_BUILD"
# GitHub Actions has "GITHUB_ACTIONS"
return (
"CI" in os.environ or "TF_BUILD" in os.environ or "GITHUB_ACTIONS" in os.environ
)
def is_win32():
return sys.platform.startswith("win32")
def is_pypy():
return hasattr(sys, "pypy_translation_info")
if sys.platform == "win32":
IMCONVERT = os.environ.get("MAGICK_HOME", "")
if IMCONVERT:
IMCONVERT = os.path.join(IMCONVERT, "convert.exe")
else:
IMCONVERT = "convert"
def distro():
if os.path.exists("/etc/os-release"):
with open("/etc/os-release", "r") as f:
for line in f:
if "ID=" in line:
return line.strip().split("=")[1]
class cached_property(object):
def __init__(self, func):
self.func = func
def __get__(self, instance, cls=None):
result = instance.__dict__[self.func.__name__] = self.func(instance)
return result