diff options
Diffstat (limited to 'lib-python/2.7/test/test_pow.py')
| -rw-r--r-- | lib-python/2.7/test/test_pow.py | 129 |
1 files changed, 129 insertions, 0 deletions
diff --git a/lib-python/2.7/test/test_pow.py b/lib-python/2.7/test/test_pow.py new file mode 100644 index 0000000000..1ee67bc452 --- /dev/null +++ b/lib-python/2.7/test/test_pow.py @@ -0,0 +1,129 @@ +import test.test_support, unittest + +class PowTest(unittest.TestCase): + + def powtest(self, type): + if type != float: + for i in range(-1000, 1000): + self.assertEqual(pow(type(i), 0), 1) + self.assertEqual(pow(type(i), 1), type(i)) + self.assertEqual(pow(type(0), 1), type(0)) + self.assertEqual(pow(type(1), 1), type(1)) + + for i in range(-100, 100): + self.assertEqual(pow(type(i), 3), i*i*i) + + pow2 = 1 + for i in range(0,31): + self.assertEqual(pow(2, i), pow2) + if i != 30 : pow2 = pow2*2 + + for othertype in int, long: + for i in range(-10, 0) + range(1, 10): + ii = type(i) + for j in range(1, 11): + jj = -othertype(j) + pow(ii, jj) + + for othertype in int, long, float: + for i in range(1, 100): + zero = type(0) + exp = -othertype(i/10.0) + if exp == 0: + continue + self.assertRaises(ZeroDivisionError, pow, zero, exp) + + il, ih = -20, 20 + jl, jh = -5, 5 + kl, kh = -10, 10 + asseq = self.assertEqual + if type == float: + il = 1 + asseq = self.assertAlmostEqual + elif type == int: + jl = 0 + elif type == long: + jl, jh = 0, 15 + for i in range(il, ih+1): + for j in range(jl, jh+1): + for k in range(kl, kh+1): + if k != 0: + if type == float or j < 0: + self.assertRaises(TypeError, pow, type(i), j, k) + continue + asseq( + pow(type(i),j,k), + pow(type(i),j)% type(k) + ) + + def test_powint(self): + self.powtest(int) + + def test_powlong(self): + self.powtest(long) + + def test_powfloat(self): + self.powtest(float) + + def test_other(self): + # Other tests-- not very systematic + self.assertEqual(pow(3,3) % 8, pow(3,3,8)) + self.assertEqual(pow(3,3) % -8, pow(3,3,-8)) + self.assertEqual(pow(3,2) % -2, pow(3,2,-2)) + self.assertEqual(pow(-3,3) % 8, pow(-3,3,8)) + self.assertEqual(pow(-3,3) % -8, pow(-3,3,-8)) + self.assertEqual(pow(5,2) % -8, pow(5,2,-8)) + + self.assertEqual(pow(3L,3L) % 8, pow(3L,3L,8)) + self.assertEqual(pow(3L,3L) % -8, pow(3L,3L,-8)) + self.assertEqual(pow(3L,2) % -2, pow(3L,2,-2)) + self.assertEqual(pow(-3L,3L) % 8, pow(-3L,3L,8)) + self.assertEqual(pow(-3L,3L) % -8, pow(-3L,3L,-8)) + self.assertEqual(pow(5L,2) % -8, pow(5L,2,-8)) + + for i in range(-10, 11): + for j in range(0, 6): + for k in range(-7, 11): + if j >= 0 and k != 0: + self.assertEqual( + pow(i,j) % k, + pow(i,j,k) + ) + if j >= 0 and k != 0: + self.assertEqual( + pow(long(i),j) % k, + pow(long(i),j,k) + ) + + def test_bug643260(self): + class TestRpow: + def __rpow__(self, other): + return None + None ** TestRpow() # Won't fail when __rpow__ invoked. SF bug #643260. + + def test_bug705231(self): + # -1.0 raised to an integer should never blow up. It did if the + # platform pow() was buggy, and Python didn't worm around it. + eq = self.assertEqual + a = -1.0 + # The next two tests can still fail if the platform floor() + # function doesn't treat all large inputs as integers + # test_math should also fail if that is happening + eq(pow(a, 1.23e167), 1.0) + eq(pow(a, -1.23e167), 1.0) + for b in range(-10, 11): + eq(pow(a, float(b)), b & 1 and -1.0 or 1.0) + for n in range(0, 100): + fiveto = float(5 ** n) + # For small n, fiveto will be odd. Eventually we run out of + # mantissa bits, though, and thereafer fiveto will be even. + expected = fiveto % 2.0 and -1.0 or 1.0 + eq(pow(a, fiveto), expected) + eq(pow(a, -fiveto), expected) + eq(expected, 1.0) # else we didn't push fiveto to evenness + +def test_main(): + test.test_support.run_unittest(PowTest) + +if __name__ == "__main__": + test_main() |