Pillow/Tests/test_tiff_ifdrational.py
2016-01-24 12:44:31 +11:00

62 lines
1.7 KiB
Python

from __future__ import print_function
from helper import PillowTestCase, hopper
from PIL import TiffImagePlugin, Image
from PIL.TiffImagePlugin import IFDRational
from fractions import Fraction
class Test_IFDRational(PillowTestCase):
def _test_equal(self, num, denom, target):
t = IFDRational(num, denom)
self.assertEqual(target, t)
self.assertEqual(t, target)
def test_sanity(self):
self._test_equal(1, 1, 1)
self._test_equal(1, 1, Fraction(1,1))
self._test_equal(2, 2, 1)
self._test_equal(1.0, 1, Fraction(1,1))
self._test_equal(Fraction(1,1), 1, Fraction(1,1))
self._test_equal(IFDRational(1,1), 1, 1)
self._test_equal(1, 2, Fraction(1,2))
self._test_equal(1, 2, IFDRational(1,2))
def test_nonetype(self):
" Fails if the _delegate function doesn't return a valid function"
xres = IFDRational(72)
yres = IFDRational(72)
self.assertTrue(xres._val is not None)
self.assertTrue(xres.numerator is not None)
self.assertTrue(xres.denominator is not None)
self.assertTrue(yres._val is not None)
self.assertTrue(xres and 1)
self.assertTrue(xres and yres)
def test_ifd_rational_save(self):
for libtiff in (True, False):
TiffImagePlugin.WRITE_LIBTIFF = libtiff
im = hopper()
out = self.tempfile('temp.tiff')
res = IFDRational(301,1)
im.save(out, dpi=(res,res), compression='raw')
reloaded = Image.open(out)
self.assertEqual(float(IFDRational(301,1)),
float(reloaded.tag_v2[282]))