import test.test_support, unittest

class PowTest(unittest.TestCase):

    def powtest(self, type):

        if type != float:

            for i in range(-1000, 1000):

                self.assertEquals(pow(type(i), 0), 1)

                self.assertEquals(pow(type(i), 1), type(i))

                self.assertEquals(pow(type(0), 1), type(0))

                self.assertEquals(pow(type(1), 1), type(1))

            for i in range(-100, 100):

                self.assertEquals(pow(type(i), 3), i*i*i)

            pow2 = 1

            for i in range(0,31):

                self.assertEquals(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.assertEquals(pow(3,3) % 8, pow(3,3,8))

        self.assertEquals(pow(3,3) % -8, pow(3,3,-8))

        self.assertEquals(pow(3,2) % -2, pow(3,2,-2))

        self.assertEquals(pow(-3,3) % 8, pow(-3,3,8))

        self.assertEquals(pow(-3,3) % -8, pow(-3,3,-8))

        self.assertEquals(pow(5,2) % -8, pow(5,2,-8))

        self.assertEquals(pow(3L,3L) % 8, pow(3L,3L,8))

        self.assertEquals(pow(3L,3L) % -8, pow(3L,3L,-8))

        self.assertEquals(pow(3L,2) % -2, pow(3L,2,-2))

        self.assertEquals(pow(-3L,3L) % 8, pow(-3L,3L,8))

        self.assertEquals(pow(-3L,3L) % -8, pow(-3L,3L,-8))

        self.assertEquals(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.assertEquals(

                            pow(i,j) % k,

                            pow(i,j,k)

                        )

                    if j >= 0 and k != 0:

                        self.assertEquals(

                            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.assertEquals

        a = -1.0

        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()