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 = 1 << 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(1 / huge, 0.0) self.assertEqual(1 / mhuge, 0.0) self.assertEqual(1 / 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 / 2", "huge / -1", "huge / -2", "mhuge / 100", "mhuge / 200"]: # 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", "2 / huge", "-1 / huge", "-2 / huge", "100 / mhuge", "200 / mhuge"]: result = eval(underflow, namespace) self.assertEqual(result, 0.0, "expected underflow to 0 from %r" % underflow) for zero in ["huge / 0", "mhuge / 0"]: self.assertRaises(ZeroDivisionError, eval, zero, namespace) def test_main(): run_unittest(TrueDivisionTests) if __name__ == "__main__": test_main()