Pillow/Tests/check_large_memory.py

import sys
import unittest

from PIL import Image

from .helper import PillowTestCase

# This test is not run automatically.
#
# It requires > 2gb memory for the >2 gigapixel image generated in the
# second test.  Running this automatically would amount to a denial of
# service on our testing infrastructure.  I expect this test to fail
# on any 32-bit machine, as well as any smallish things (like
# Raspberry Pis). It does succeed on a 3gb Ubuntu 12.04x64 VM on Python
# 2.7 and 3.2.


try:
    import numpy
except ImportError:
    numpy = None

YDIM = 32769
XDIM = 48000


@unittest.skipIf(sys.maxsize <= 2 ** 32, "requires 64-bit system")
class LargeMemoryTest(PillowTestCase):
    def _write_png(self, xdim, ydim):
        f = self.tempfile("temp.png")
        im = Image.new("L", (xdim, ydim), 0)
        im.save(f)

    def test_large(self):
        """ succeeded prepatch"""
        self._write_png(XDIM, YDIM)

    def test_2gpx(self):
        """failed prepatch"""
        self._write_png(XDIM, XDIM)

    @unittest.skipIf(numpy is None, "Numpy is not installed")
    def test_size_greater_than_int(self):
        arr = numpy.ndarray(shape=(16394, 16394))
        Image.fromarray(arr)


if __name__ == "__main__":
    unittest.main()