from __future__ import division

# When true division is the default, get rid of this and add it to

# test_long.py instead.  In the meantime, it's too obscure to try to

# trick just part of test_long into using future division.

import unittest

from test.test_support import run_unittest

class TrueDivisionTests(unittest.TestCase):

    def test(self):

        huge = 1L << 40000

        mhuge = -huge

        self.assertEqual(huge / huge, 1.0)

        self.assertEqual(mhuge / mhuge, 1.0)

        self.assertEqual(huge / mhuge, -1.0)

        self.assertEqual(mhuge / huge, -1.0)

        self.assertEqual(1 / huge, 0.0)

        self.assertEqual(1L / huge, 0.0)

        self.assertEqual(1 / mhuge, 0.0)

        self.assertEqual(1L / mhuge, 0.0)

        self.assertEqual((666 * huge + (huge >> 1)) / huge, 666.5)

        self.assertEqual((666 * mhuge + (mhuge >> 1)) / mhuge, 666.5)

        self.assertEqual((666 * huge + (huge >> 1)) / mhuge, -666.5)

        self.assertEqual((666 * mhuge + (mhuge >> 1)) / huge, -666.5)

        self.assertEqual(huge / (huge << 1), 0.5)

        self.assertEqual((1000000 * huge) / huge, 1000000)

        namespace = {'huge': huge, 'mhuge': mhuge}

        for overflow in ["float(huge)", "float(mhuge)",

                         "huge / 1", "huge / 2L", "huge / -1", "huge / -2L",

                         "mhuge / 100", "mhuge / 100L"]:

            # XXX(cwinter) this test doesn't pass when converted to

            # use assertRaises.

            try:

                eval(overflow, namespace)

                self.fail("expected OverflowError from %r" % overflow)

            except OverflowError:

                pass

        for underflow in ["1 / huge", "2L / huge", "-1 / huge", "-2L / huge",

                         "100 / mhuge", "100L / mhuge"]:

            result = eval(underflow, namespace)

            self.assertEqual(result, 0.0,

                             "expected underflow to 0 from %r" % underflow)

        for zero in ["huge / 0", "huge / 0L", "mhuge / 0", "mhuge / 0L"]:

            self.assertRaises(ZeroDivisionError, eval, zero, namespace)

def test_main():

    run_unittest(TrueDivisionTests)

if __name__ == "__main__":

    test_main()