Pillow/Tests/tester.py

from __future__ import print_function

# require that deprecation warnings are triggered
import warnings
warnings.simplefilter('default')
# temporarily turn off resource warnings that warn about unclosed
# files in the test scripts.
try:
    warnings.filterwarnings("ignore", category=ResourceWarning)
except NameError:
    # we expect a NameError on py2.x, since it doesn't have ResourceWarnings.
    pass

import sys
py3 = (sys.version_info >= (3, 0))

# some test helpers

_target = None
_tempfiles = []
_logfile = None


def success():
    import sys
    success.count += 1
    if _logfile:
        print(sys.argv[0], success.count, failure.count, file=_logfile)
    return True


def failure(msg=None, frame=None):
    import sys
    import linecache
    failure.count += 1
    if _target:
        if frame is None:
            frame = sys._getframe()
            while frame.f_globals.get("__name__") != _target.__name__:
                frame = frame.f_back
        location = (frame.f_code.co_filename, frame.f_lineno)
        prefix = "%s:%d: " % location
        line = linecache.getline(*location)
        print(prefix + line.strip() + " failed:")
    if msg:
        print("- " + msg)
    if _logfile:
        print(sys.argv[0], success.count, failure.count, file=_logfile)
    return False

success.count = failure.count = 0


# predicates

def assert_true(v, msg=None):
    if v:
        success()
    else:
        failure(msg or "got %r, expected true value" % v)


def assert_false(v, msg=None):
    if v:
        failure(msg or "got %r, expected false value" % v)
    else:
        success()


def assert_equal(a, b, msg=None):
    if a == b:
        success()
    else:
        failure(msg or "got %r, expected %r" % (a, b))


def assert_almost_equal(a, b, msg=None, eps=1e-6):
    if abs(a-b) < eps:
        success()
    else:
        failure(msg or "got %r, expected %r" % (a, b))


def assert_deep_equal(a, b, msg=None):
    try:
        if len(a) == len(b):
            if all([x == y for x, y in zip(a, b)]):
                success()
            else:
                failure(msg or "got %s, expected %s" % (a, b))
        else:
            failure(msg or "got length %s, expected %s" % (len(a), len(b)))
    except:
        assert_equal(a, b, msg)


def assert_greater(a, b, msg=None):
    if a > b:
        success()
    else:
        failure(msg or "%r unexpectedly not greater than %r" % (a, b))


def assert_greater_equal(a, b, msg=None):
    if a >= b:
        success()
    else:
        failure(
            msg or "%r unexpectedly not greater than or equal to %r" % (a, b))


def assert_less(a, b, msg=None):
    if a < b:
        success()
    else:
        failure(msg or "%r unexpectedly not less than %r" % (a, b))


def assert_less_equal(a, b, msg=None):
    if a <= b:
        success()
    else:
        failure(
            msg or "%r unexpectedly not less than or equal to %r" % (a, b))


def assert_is_instance(a, b, msg=None):
    if isinstance(a, b):
        success()
    else:
        failure(msg or "got %r, expected %r" % (type(a), b))


def assert_in(a, b, msg=None):
    if a in b:
        success()
    else:
        failure(msg or "%r unexpectedly not in %r" % (a, b))


def assert_match(v, pattern, msg=None):
    import re
    if re.match(pattern, v):
        success()
    else:
        failure(msg or "got %r, doesn't match pattern %r" % (v, pattern))


def assert_exception(exc_class, func):
    import sys
    import traceback
    try:
        func()
    except exc_class:
        success()
    except:
        failure("expected %r exception, got %r" % (
                exc_class.__name__, sys.exc_info()[0].__name__))
        traceback.print_exc()
    else:
        failure("expected %r exception, got no exception" % exc_class.__name__)


def assert_no_exception(func):
    import sys
    import traceback
    try:
        func()
    except:
        failure("expected no exception, got %r" % sys.exc_info()[0].__name__)
        traceback.print_exc()
    else:
        success()


def assert_warning(warn_class, func):
    # note: this assert calls func three times!
    import warnings

    def warn_error(message, category=UserWarning, **options):
        raise category(message)

    def warn_ignore(message, category=UserWarning, **options):
        pass
    warn = warnings.warn
    result = None
    try:
        warnings.warn = warn_ignore
        assert_no_exception(func)
        result = func()
        warnings.warn = warn_error
        assert_exception(warn_class, func)
    finally:
        warnings.warn = warn  # restore
    return result

# helpers

from io import BytesIO


def fromstring(data):
    from PIL import Image
    return Image.open(BytesIO(data))


def tostring(im, format, **options):
    out = BytesIO()
    im.save(out, format, **options)
    return out.getvalue()


def lena(mode="RGB", cache={}):
    from PIL import Image
    im = cache.get(mode)
    if im is None:
        if mode == "RGB":
            im = Image.open("Images/lena.ppm")
        elif mode == "F":
            im = lena("L").convert(mode)
        elif mode[:4] == "I;16":
            im = lena("I").convert(mode)
        else:
            im = lena("RGB").convert(mode)
    cache[mode] = im
    return im


def assert_image(im, mode, size, msg=None):
    if mode is not None and im.mode != mode:
        failure(msg or "got mode %r, expected %r" % (im.mode, mode))
    elif size is not None and im.size != size:
        failure(msg or "got size %r, expected %r" % (im.size, size))
    else:
        success()


def assert_image_equal(a, b, msg=None):
    if a.mode != b.mode:
        failure(msg or "got mode %r, expected %r" % (a.mode, b.mode))
    elif a.size != b.size:
        failure(msg or "got size %r, expected %r" % (a.size, b.size))
    elif a.tobytes() != b.tobytes():
        failure(msg or "got different content")
        # generate better diff?
    else:
        success()


def assert_image_similar(a, b, epsilon, msg=None):
    epsilon = float(epsilon)
    if a.mode != b.mode:
        return failure(msg or "got mode %r, expected %r" % (a.mode, b.mode))
    elif a.size != b.size:
        return failure(msg or "got size %r, expected %r" % (a.size, b.size))
    diff = 0
    try:
        ord(b'0')
        for abyte, bbyte in zip(a.tobytes(), b.tobytes()):
            diff += abs(ord(abyte)-ord(bbyte))
    except:
        for abyte, bbyte in zip(a.tobytes(), b.tobytes()):
            diff += abs(abyte-bbyte)
    ave_diff = float(diff)/(a.size[0]*a.size[1])
    if epsilon < ave_diff:
        return failure(
            msg or "average pixel value difference %.4f > epsilon %.4f" % (
                ave_diff, epsilon))
    else:
        return success()


def tempfile(template, *extra):
    import os
    import os.path
    import sys
    import tempfile
    files = []
    root = os.path.join(tempfile.gettempdir(), 'pillow-tests')
    try:
        os.mkdir(root)
    except OSError:
        pass
    for temp in (template,) + extra:
        assert temp[:5] in ("temp.", "temp_")
        name = os.path.basename(sys.argv[0])
        name = temp[:4] + os.path.splitext(name)[0][4:]
        name = name + "_%d" % len(_tempfiles) + temp[4:]
        name = os.path.join(root, name)
        files.append(name)
    _tempfiles.extend(files)
    return files[0]


# test runner

def run():
    global _target, _tests, run
    import sys
    import traceback
    _target = sys.modules["__main__"]
    run = None  # no need to run twice
    tests = []
    for name, value in list(vars(_target).items()):
        if name[:5] == "test_" and type(value) is type(success):
            tests.append((value.__code__.co_firstlineno, name, value))
    tests.sort()  # sort by line
    for lineno, name, func in tests:
        try:
            _tests = []
            func()
            for func, args in _tests:
                func(*args)
        except:
            t, v, tb = sys.exc_info()
            tb = tb.tb_next
            if tb:
                failure(frame=tb.tb_frame)
                traceback.print_exception(t, v, tb)
            else:
                print("%s:%d: cannot call test function: %s" % (
                    sys.argv[0], lineno, v))
                failure.count += 1


def yield_test(function, *args):
    # collect delayed/generated tests
    _tests.append((function, args))


def skip(msg=None):
    import os
    print("skip")
    os._exit(0)  # don't run exit handlers


def ignore(pattern):
    """Tells the driver to ignore messages matching the pattern, for the
    duration of the current test."""
    print('ignore: %s' % pattern)


def _setup():
    global _logfile

    import sys
    if "--coverage" in sys.argv:
        # Temporary: ignore PendingDeprecationWarning from Coverage (Py3.4)
        with warnings.catch_warnings():
            warnings.simplefilter("ignore")
            import coverage
        cov = coverage.coverage(auto_data=True, include="PIL/*")
        cov.start()

    def report():
        if run:
            run()
        if success.count and not failure.count:
            print("ok")
            # only clean out tempfiles if test passed
            import os
            import os.path
            import tempfile
            for file in _tempfiles:
                try:
                    os.remove(file)
                except OSError:
                    pass  # report?
            temp_root = os.path.join(tempfile.gettempdir(), 'pillow-tests')
            try:
                os.rmdir(temp_root)
            except OSError:
                pass

    import atexit
    atexit.register(report)

    if "--log" in sys.argv:
        _logfile = open("test.log", "a")


_setup()