Revision 070fae6d0ff49e63bfd5f2bdc66f8eb1df3b6557 authored by Christian Heimes on 02 July 2019, 18:39:42 UTC, committed by Ned Deily on 02 July 2019, 18:42:08 UTC


ssl.match_hostname() no longer accepts IPv4 addresses with additional text
after the address and only quad-dotted notation without trailing
whitespaces. Some inet_aton() implementations ignore whitespace and all data
after whitespace, e.g. '127.0.0.1 whatever'.

Short notations like '127.1' for '127.0.0.1' were already filtered out.

The bug was initially found by Dominik Czarnota and reported by Paul Kehrer.

Signed-off-by: Christian Heimes <christian@python.org>



https://bugs.python.org/issue37463
1 parent dcc0eb3
Raw File
test_fractions.py
"""Tests for Lib/fractions.py."""

from decimal import Decimal
from test.support import requires_IEEE_754
import math
import numbers
import operator
import fractions
import sys
import unittest
import warnings
from copy import copy, deepcopy
from pickle import dumps, loads
F = fractions.Fraction
gcd = fractions.gcd

class DummyFloat(object):
    """Dummy float class for testing comparisons with Fractions"""

    def __init__(self, value):
        if not isinstance(value, float):
            raise TypeError("DummyFloat can only be initialized from float")
        self.value = value

    def _richcmp(self, other, op):
        if isinstance(other, numbers.Rational):
            return op(F.from_float(self.value), other)
        elif isinstance(other, DummyFloat):
            return op(self.value, other.value)
        else:
            return NotImplemented

    def __eq__(self, other): return self._richcmp(other, operator.eq)
    def __le__(self, other): return self._richcmp(other, operator.le)
    def __lt__(self, other): return self._richcmp(other, operator.lt)
    def __ge__(self, other): return self._richcmp(other, operator.ge)
    def __gt__(self, other): return self._richcmp(other, operator.gt)

    # shouldn't be calling __float__ at all when doing comparisons
    def __float__(self):
        assert False, "__float__ should not be invoked for comparisons"

    # same goes for subtraction
    def __sub__(self, other):
        assert False, "__sub__ should not be invoked for comparisons"
    __rsub__ = __sub__


class DummyRational(object):
    """Test comparison of Fraction with a naive rational implementation."""

    def __init__(self, num, den):
        g = math.gcd(num, den)
        self.num = num // g
        self.den = den // g

    def __eq__(self, other):
        if isinstance(other, fractions.Fraction):
            return (self.num == other._numerator and
                    self.den == other._denominator)
        else:
            return NotImplemented

    def __lt__(self, other):
        return(self.num * other._denominator < self.den * other._numerator)

    def __gt__(self, other):
        return(self.num * other._denominator > self.den * other._numerator)

    def __le__(self, other):
        return(self.num * other._denominator <= self.den * other._numerator)

    def __ge__(self, other):
        return(self.num * other._denominator >= self.den * other._numerator)

    # this class is for testing comparisons; conversion to float
    # should never be used for a comparison, since it loses accuracy
    def __float__(self):
        assert False, "__float__ should not be invoked"

class DummyFraction(fractions.Fraction):
    """Dummy Fraction subclass for copy and deepcopy testing."""

class GcdTest(unittest.TestCase):

    def testMisc(self):
        # fractions.gcd() is deprecated
        with self.assertWarnsRegex(DeprecationWarning, r'fractions\.gcd'):
            gcd(1, 1)
        with warnings.catch_warnings():
            warnings.filterwarnings('ignore', r'fractions\.gcd',
                                    DeprecationWarning)
            self.assertEqual(0, gcd(0, 0))
            self.assertEqual(1, gcd(1, 0))
            self.assertEqual(-1, gcd(-1, 0))
            self.assertEqual(1, gcd(0, 1))
            self.assertEqual(-1, gcd(0, -1))
            self.assertEqual(1, gcd(7, 1))
            self.assertEqual(-1, gcd(7, -1))
            self.assertEqual(1, gcd(-23, 15))
            self.assertEqual(12, gcd(120, 84))
            self.assertEqual(-12, gcd(84, -120))
            self.assertEqual(gcd(120.0, 84), 12.0)
            self.assertEqual(gcd(120, 84.0), 12.0)
            self.assertEqual(gcd(F(120), F(84)), F(12))
            self.assertEqual(gcd(F(120, 77), F(84, 55)), F(12, 385))


def _components(r):
    return (r.numerator, r.denominator)


class FractionTest(unittest.TestCase):

    def assertTypedEquals(self, expected, actual):
        """Asserts that both the types and values are the same."""
        self.assertEqual(type(expected), type(actual))
        self.assertEqual(expected, actual)

    def assertRaisesMessage(self, exc_type, message,
                            callable, *args, **kwargs):
        """Asserts that callable(*args, **kwargs) raises exc_type(message)."""
        try:
            callable(*args, **kwargs)
        except exc_type as e:
            self.assertEqual(message, str(e))
        else:
            self.fail("%s not raised" % exc_type.__name__)

    def testInit(self):
        self.assertEqual((0, 1), _components(F()))
        self.assertEqual((7, 1), _components(F(7)))
        self.assertEqual((7, 3), _components(F(F(7, 3))))

        self.assertEqual((-1, 1), _components(F(-1, 1)))
        self.assertEqual((-1, 1), _components(F(1, -1)))
        self.assertEqual((1, 1), _components(F(-2, -2)))
        self.assertEqual((1, 2), _components(F(5, 10)))
        self.assertEqual((7, 15), _components(F(7, 15)))
        self.assertEqual((10**23, 1), _components(F(10**23)))

        self.assertEqual((3, 77), _components(F(F(3, 7), 11)))
        self.assertEqual((-9, 5), _components(F(2, F(-10, 9))))
        self.assertEqual((2486, 2485), _components(F(F(22, 7), F(355, 113))))

        self.assertRaisesMessage(ZeroDivisionError, "Fraction(12, 0)",
                                 F, 12, 0)
        self.assertRaises(TypeError, F, 1.5 + 3j)

        self.assertRaises(TypeError, F, "3/2", 3)
        self.assertRaises(TypeError, F, 3, 0j)
        self.assertRaises(TypeError, F, 3, 1j)
        self.assertRaises(TypeError, F, 1, 2, 3)

    @requires_IEEE_754
    def testInitFromFloat(self):
        self.assertEqual((5, 2), _components(F(2.5)))
        self.assertEqual((0, 1), _components(F(-0.0)))
        self.assertEqual((3602879701896397, 36028797018963968),
                         _components(F(0.1)))
        # bug 16469: error types should be consistent with float -> int
        self.assertRaises(ValueError, F, float('nan'))
        self.assertRaises(OverflowError, F, float('inf'))
        self.assertRaises(OverflowError, F, float('-inf'))

    def testInitFromDecimal(self):
        self.assertEqual((11, 10),
                         _components(F(Decimal('1.1'))))
        self.assertEqual((7, 200),
                         _components(F(Decimal('3.5e-2'))))
        self.assertEqual((0, 1),
                         _components(F(Decimal('.000e20'))))
        # bug 16469: error types should be consistent with decimal -> int
        self.assertRaises(ValueError, F, Decimal('nan'))
        self.assertRaises(ValueError, F, Decimal('snan'))
        self.assertRaises(OverflowError, F, Decimal('inf'))
        self.assertRaises(OverflowError, F, Decimal('-inf'))

    def testFromString(self):
        self.assertEqual((5, 1), _components(F("5")))
        self.assertEqual((3, 2), _components(F("3/2")))
        self.assertEqual((3, 2), _components(F(" \n  +3/2")))
        self.assertEqual((-3, 2), _components(F("-3/2  ")))
        self.assertEqual((13, 2), _components(F("    013/02 \n  ")))
        self.assertEqual((16, 5), _components(F(" 3.2 ")))
        self.assertEqual((-16, 5), _components(F(" -3.2 ")))
        self.assertEqual((-3, 1), _components(F(" -3. ")))
        self.assertEqual((3, 5), _components(F(" .6 ")))
        self.assertEqual((1, 3125), _components(F("32.e-5")))
        self.assertEqual((1000000, 1), _components(F("1E+06")))
        self.assertEqual((-12300, 1), _components(F("-1.23e4")))
        self.assertEqual((0, 1), _components(F(" .0e+0\t")))
        self.assertEqual((0, 1), _components(F("-0.000e0")))

        self.assertRaisesMessage(
            ZeroDivisionError, "Fraction(3, 0)",
            F, "3/0")
        self.assertRaisesMessage(
            ValueError, "Invalid literal for Fraction: '3/'",
            F, "3/")
        self.assertRaisesMessage(
            ValueError, "Invalid literal for Fraction: '/2'",
            F, "/2")
        self.assertRaisesMessage(
            ValueError, "Invalid literal for Fraction: '3 /2'",
            F, "3 /2")
        self.assertRaisesMessage(
            # Denominators don't need a sign.
            ValueError, "Invalid literal for Fraction: '3/+2'",
            F, "3/+2")
        self.assertRaisesMessage(
            # Imitate float's parsing.
            ValueError, "Invalid literal for Fraction: '+ 3/2'",
            F, "+ 3/2")
        self.assertRaisesMessage(
            # Avoid treating '.' as a regex special character.
            ValueError, "Invalid literal for Fraction: '3a2'",
            F, "3a2")
        self.assertRaisesMessage(
            # Don't accept combinations of decimals and rationals.
            ValueError, "Invalid literal for Fraction: '3/7.2'",
            F, "3/7.2")
        self.assertRaisesMessage(
            # Don't accept combinations of decimals and rationals.
            ValueError, "Invalid literal for Fraction: '3.2/7'",
            F, "3.2/7")
        self.assertRaisesMessage(
            # Allow 3. and .3, but not .
            ValueError, "Invalid literal for Fraction: '.'",
            F, ".")

    def testImmutable(self):
        r = F(7, 3)
        r.__init__(2, 15)
        self.assertEqual((7, 3), _components(r))

        self.assertRaises(AttributeError, setattr, r, 'numerator', 12)
        self.assertRaises(AttributeError, setattr, r, 'denominator', 6)
        self.assertEqual((7, 3), _components(r))

        # But if you _really_ need to:
        r._numerator = 4
        r._denominator = 2
        self.assertEqual((4, 2), _components(r))
        # Which breaks some important operations:
        self.assertNotEqual(F(4, 2), r)

    def testFromFloat(self):
        self.assertRaises(TypeError, F.from_float, 3+4j)
        self.assertEqual((10, 1), _components(F.from_float(10)))
        bigint = 1234567890123456789
        self.assertEqual((bigint, 1), _components(F.from_float(bigint)))
        self.assertEqual((0, 1), _components(F.from_float(-0.0)))
        self.assertEqual((10, 1), _components(F.from_float(10.0)))
        self.assertEqual((-5, 2), _components(F.from_float(-2.5)))
        self.assertEqual((99999999999999991611392, 1),
                         _components(F.from_float(1e23)))
        self.assertEqual(float(10**23), float(F.from_float(1e23)))
        self.assertEqual((3602879701896397, 1125899906842624),
                         _components(F.from_float(3.2)))
        self.assertEqual(3.2, float(F.from_float(3.2)))

        inf = 1e1000
        nan = inf - inf
        # bug 16469: error types should be consistent with float -> int
        self.assertRaisesMessage(
            OverflowError, "cannot convert Infinity to integer ratio",
            F.from_float, inf)
        self.assertRaisesMessage(
            OverflowError, "cannot convert Infinity to integer ratio",
            F.from_float, -inf)
        self.assertRaisesMessage(
            ValueError, "cannot convert NaN to integer ratio",
            F.from_float, nan)

    def testFromDecimal(self):
        self.assertRaises(TypeError, F.from_decimal, 3+4j)
        self.assertEqual(F(10, 1), F.from_decimal(10))
        self.assertEqual(F(0), F.from_decimal(Decimal("-0")))
        self.assertEqual(F(5, 10), F.from_decimal(Decimal("0.5")))
        self.assertEqual(F(5, 1000), F.from_decimal(Decimal("5e-3")))
        self.assertEqual(F(5000), F.from_decimal(Decimal("5e3")))
        self.assertEqual(1 - F(1, 10**30),
                         F.from_decimal(Decimal("0." + "9" * 30)))

        # bug 16469: error types should be consistent with decimal -> int
        self.assertRaisesMessage(
            OverflowError, "cannot convert Infinity to integer ratio",
            F.from_decimal, Decimal("inf"))
        self.assertRaisesMessage(
            OverflowError, "cannot convert Infinity to integer ratio",
            F.from_decimal, Decimal("-inf"))
        self.assertRaisesMessage(
            ValueError, "cannot convert NaN to integer ratio",
            F.from_decimal, Decimal("nan"))
        self.assertRaisesMessage(
            ValueError, "cannot convert NaN to integer ratio",
            F.from_decimal, Decimal("snan"))

    def testLimitDenominator(self):
        rpi = F('3.1415926535897932')
        self.assertEqual(rpi.limit_denominator(10000), F(355, 113))
        self.assertEqual(-rpi.limit_denominator(10000), F(-355, 113))
        self.assertEqual(rpi.limit_denominator(113), F(355, 113))
        self.assertEqual(rpi.limit_denominator(112), F(333, 106))
        self.assertEqual(F(201, 200).limit_denominator(100), F(1))
        self.assertEqual(F(201, 200).limit_denominator(101), F(102, 101))
        self.assertEqual(F(0).limit_denominator(10000), F(0))
        for i in (0, -1):
            self.assertRaisesMessage(
                ValueError, "max_denominator should be at least 1",
                F(1).limit_denominator, i)

    def testConversions(self):
        self.assertTypedEquals(-1, math.trunc(F(-11, 10)))
        self.assertTypedEquals(1, math.trunc(F(11, 10)))
        self.assertTypedEquals(-2, math.floor(F(-11, 10)))
        self.assertTypedEquals(-1, math.ceil(F(-11, 10)))
        self.assertTypedEquals(-1, math.ceil(F(-10, 10)))
        self.assertTypedEquals(-1, int(F(-11, 10)))
        self.assertTypedEquals(0, round(F(-1, 10)))
        self.assertTypedEquals(0, round(F(-5, 10)))
        self.assertTypedEquals(-2, round(F(-15, 10)))
        self.assertTypedEquals(-1, round(F(-7, 10)))

        self.assertEqual(False, bool(F(0, 1)))
        self.assertEqual(True, bool(F(3, 2)))
        self.assertTypedEquals(0.1, float(F(1, 10)))

        # Check that __float__ isn't implemented by converting the
        # numerator and denominator to float before dividing.
        self.assertRaises(OverflowError, float, int('2'*400+'7'))
        self.assertAlmostEqual(2.0/3,
                               float(F(int('2'*400+'7'), int('3'*400+'1'))))

        self.assertTypedEquals(0.1+0j, complex(F(1,10)))

    def testRound(self):
        self.assertTypedEquals(F(-200), round(F(-150), -2))
        self.assertTypedEquals(F(-200), round(F(-250), -2))
        self.assertTypedEquals(F(30), round(F(26), -1))
        self.assertTypedEquals(F(-2, 10), round(F(-15, 100), 1))
        self.assertTypedEquals(F(-2, 10), round(F(-25, 100), 1))

    def testArithmetic(self):
        self.assertEqual(F(1, 2), F(1, 10) + F(2, 5))
        self.assertEqual(F(-3, 10), F(1, 10) - F(2, 5))
        self.assertEqual(F(1, 25), F(1, 10) * F(2, 5))
        self.assertEqual(F(1, 4), F(1, 10) / F(2, 5))
        self.assertTypedEquals(2, F(9, 10) // F(2, 5))
        self.assertTypedEquals(10**23, F(10**23, 1) // F(1))
        self.assertEqual(F(2, 3), F(-7, 3) % F(3, 2))
        self.assertEqual(F(8, 27), F(2, 3) ** F(3))
        self.assertEqual(F(27, 8), F(2, 3) ** F(-3))
        self.assertTypedEquals(2.0, F(4) ** F(1, 2))
        self.assertEqual(F(1, 1), +F(1, 1))
        z = pow(F(-1), F(1, 2))
        self.assertAlmostEqual(z.real, 0)
        self.assertEqual(z.imag, 1)
        # Regression test for #27539.
        p = F(-1, 2) ** 0
        self.assertEqual(p, F(1, 1))
        self.assertEqual(p.numerator, 1)
        self.assertEqual(p.denominator, 1)
        p = F(-1, 2) ** -1
        self.assertEqual(p, F(-2, 1))
        self.assertEqual(p.numerator, -2)
        self.assertEqual(p.denominator, 1)
        p = F(-1, 2) ** -2
        self.assertEqual(p, F(4, 1))
        self.assertEqual(p.numerator, 4)
        self.assertEqual(p.denominator, 1)

    def testMixedArithmetic(self):
        self.assertTypedEquals(F(11, 10), F(1, 10) + 1)
        self.assertTypedEquals(1.1, F(1, 10) + 1.0)
        self.assertTypedEquals(1.1 + 0j, F(1, 10) + (1.0 + 0j))
        self.assertTypedEquals(F(11, 10), 1 + F(1, 10))
        self.assertTypedEquals(1.1, 1.0 + F(1, 10))
        self.assertTypedEquals(1.1 + 0j, (1.0 + 0j) + F(1, 10))

        self.assertTypedEquals(F(-9, 10), F(1, 10) - 1)
        self.assertTypedEquals(-0.9, F(1, 10) - 1.0)
        self.assertTypedEquals(-0.9 + 0j, F(1, 10) - (1.0 + 0j))
        self.assertTypedEquals(F(9, 10), 1 - F(1, 10))
        self.assertTypedEquals(0.9, 1.0 - F(1, 10))
        self.assertTypedEquals(0.9 + 0j, (1.0 + 0j) - F(1, 10))

        self.assertTypedEquals(F(1, 10), F(1, 10) * 1)
        self.assertTypedEquals(0.1, F(1, 10) * 1.0)
        self.assertTypedEquals(0.1 + 0j, F(1, 10) * (1.0 + 0j))
        self.assertTypedEquals(F(1, 10), 1 * F(1, 10))
        self.assertTypedEquals(0.1, 1.0 * F(1, 10))
        self.assertTypedEquals(0.1 + 0j, (1.0 + 0j) * F(1, 10))

        self.assertTypedEquals(F(1, 10), F(1, 10) / 1)
        self.assertTypedEquals(0.1, F(1, 10) / 1.0)
        self.assertTypedEquals(0.1 + 0j, F(1, 10) / (1.0 + 0j))
        self.assertTypedEquals(F(10, 1), 1 / F(1, 10))
        self.assertTypedEquals(10.0, 1.0 / F(1, 10))
        self.assertTypedEquals(10.0 + 0j, (1.0 + 0j) / F(1, 10))

        self.assertTypedEquals(0, F(1, 10) // 1)
        self.assertTypedEquals(0, F(1, 10) // 1.0)
        self.assertTypedEquals(10, 1 // F(1, 10))
        self.assertTypedEquals(10**23, 10**22 // F(1, 10))
        self.assertTypedEquals(10, 1.0 // F(1, 10))

        self.assertTypedEquals(F(1, 10), F(1, 10) % 1)
        self.assertTypedEquals(0.1, F(1, 10) % 1.0)
        self.assertTypedEquals(F(0, 1), 1 % F(1, 10))
        self.assertTypedEquals(0.0, 1.0 % F(1, 10))

        # No need for divmod since we don't override it.

        # ** has more interesting conversion rules.
        self.assertTypedEquals(F(100, 1), F(1, 10) ** -2)
        self.assertTypedEquals(F(100, 1), F(10, 1) ** 2)
        self.assertTypedEquals(0.1, F(1, 10) ** 1.0)
        self.assertTypedEquals(0.1 + 0j, F(1, 10) ** (1.0 + 0j))
        self.assertTypedEquals(4 , 2 ** F(2, 1))
        z = pow(-1, F(1, 2))
        self.assertAlmostEqual(0, z.real)
        self.assertEqual(1, z.imag)
        self.assertTypedEquals(F(1, 4) , 2 ** F(-2, 1))
        self.assertTypedEquals(2.0 , 4 ** F(1, 2))
        self.assertTypedEquals(0.25, 2.0 ** F(-2, 1))
        self.assertTypedEquals(1.0 + 0j, (1.0 + 0j) ** F(1, 10))
        self.assertRaises(ZeroDivisionError, operator.pow,
                          F(0, 1), -2)

    def testMixingWithDecimal(self):
        # Decimal refuses mixed arithmetic (but not mixed comparisons)
        self.assertRaises(TypeError, operator.add,
                          F(3,11), Decimal('3.1415926'))
        self.assertRaises(TypeError, operator.add,
                          Decimal('3.1415926'), F(3,11))

    def testComparisons(self):
        self.assertTrue(F(1, 2) < F(2, 3))
        self.assertFalse(F(1, 2) < F(1, 2))
        self.assertTrue(F(1, 2) <= F(2, 3))
        self.assertTrue(F(1, 2) <= F(1, 2))
        self.assertFalse(F(2, 3) <= F(1, 2))
        self.assertTrue(F(1, 2) == F(1, 2))
        self.assertFalse(F(1, 2) == F(1, 3))
        self.assertFalse(F(1, 2) != F(1, 2))
        self.assertTrue(F(1, 2) != F(1, 3))

    def testComparisonsDummyRational(self):
        self.assertTrue(F(1, 2) == DummyRational(1, 2))
        self.assertTrue(DummyRational(1, 2) == F(1, 2))
        self.assertFalse(F(1, 2) == DummyRational(3, 4))
        self.assertFalse(DummyRational(3, 4) == F(1, 2))

        self.assertTrue(F(1, 2) < DummyRational(3, 4))
        self.assertFalse(F(1, 2) < DummyRational(1, 2))
        self.assertFalse(F(1, 2) < DummyRational(1, 7))
        self.assertFalse(F(1, 2) > DummyRational(3, 4))
        self.assertFalse(F(1, 2) > DummyRational(1, 2))
        self.assertTrue(F(1, 2) > DummyRational(1, 7))
        self.assertTrue(F(1, 2) <= DummyRational(3, 4))
        self.assertTrue(F(1, 2) <= DummyRational(1, 2))
        self.assertFalse(F(1, 2) <= DummyRational(1, 7))
        self.assertFalse(F(1, 2) >= DummyRational(3, 4))
        self.assertTrue(F(1, 2) >= DummyRational(1, 2))
        self.assertTrue(F(1, 2) >= DummyRational(1, 7))

        self.assertTrue(DummyRational(1, 2) < F(3, 4))
        self.assertFalse(DummyRational(1, 2) < F(1, 2))
        self.assertFalse(DummyRational(1, 2) < F(1, 7))
        self.assertFalse(DummyRational(1, 2) > F(3, 4))
        self.assertFalse(DummyRational(1, 2) > F(1, 2))
        self.assertTrue(DummyRational(1, 2) > F(1, 7))
        self.assertTrue(DummyRational(1, 2) <= F(3, 4))
        self.assertTrue(DummyRational(1, 2) <= F(1, 2))
        self.assertFalse(DummyRational(1, 2) <= F(1, 7))
        self.assertFalse(DummyRational(1, 2) >= F(3, 4))
        self.assertTrue(DummyRational(1, 2) >= F(1, 2))
        self.assertTrue(DummyRational(1, 2) >= F(1, 7))

    def testComparisonsDummyFloat(self):
        x = DummyFloat(1./3.)
        y = F(1, 3)
        self.assertTrue(x != y)
        self.assertTrue(x < y or x > y)
        self.assertFalse(x == y)
        self.assertFalse(x <= y and x >= y)
        self.assertTrue(y != x)
        self.assertTrue(y < x or y > x)
        self.assertFalse(y == x)
        self.assertFalse(y <= x and y >= x)

    def testMixedLess(self):
        self.assertTrue(2 < F(5, 2))
        self.assertFalse(2 < F(4, 2))
        self.assertTrue(F(5, 2) < 3)
        self.assertFalse(F(4, 2) < 2)

        self.assertTrue(F(1, 2) < 0.6)
        self.assertFalse(F(1, 2) < 0.4)
        self.assertTrue(0.4 < F(1, 2))
        self.assertFalse(0.5 < F(1, 2))

        self.assertFalse(float('inf') < F(1, 2))
        self.assertTrue(float('-inf') < F(0, 10))
        self.assertFalse(float('nan') < F(-3, 7))
        self.assertTrue(F(1, 2) < float('inf'))
        self.assertFalse(F(17, 12) < float('-inf'))
        self.assertFalse(F(144, -89) < float('nan'))

    def testMixedLessEqual(self):
        self.assertTrue(0.5 <= F(1, 2))
        self.assertFalse(0.6 <= F(1, 2))
        self.assertTrue(F(1, 2) <= 0.5)
        self.assertFalse(F(1, 2) <= 0.4)
        self.assertTrue(2 <= F(4, 2))
        self.assertFalse(2 <= F(3, 2))
        self.assertTrue(F(4, 2) <= 2)
        self.assertFalse(F(5, 2) <= 2)

        self.assertFalse(float('inf') <= F(1, 2))
        self.assertTrue(float('-inf') <= F(0, 10))
        self.assertFalse(float('nan') <= F(-3, 7))
        self.assertTrue(F(1, 2) <= float('inf'))
        self.assertFalse(F(17, 12) <= float('-inf'))
        self.assertFalse(F(144, -89) <= float('nan'))

    def testBigFloatComparisons(self):
        # Because 10**23 can't be represented exactly as a float:
        self.assertFalse(F(10**23) == float(10**23))
        # The first test demonstrates why these are important.
        self.assertFalse(1e23 < float(F(math.trunc(1e23) + 1)))
        self.assertTrue(1e23 < F(math.trunc(1e23) + 1))
        self.assertFalse(1e23 <= F(math.trunc(1e23) - 1))
        self.assertTrue(1e23 > F(math.trunc(1e23) - 1))
        self.assertFalse(1e23 >= F(math.trunc(1e23) + 1))

    def testBigComplexComparisons(self):
        self.assertFalse(F(10**23) == complex(10**23))
        self.assertRaises(TypeError, operator.gt, F(10**23), complex(10**23))
        self.assertRaises(TypeError, operator.le, F(10**23), complex(10**23))

        x = F(3, 8)
        z = complex(0.375, 0.0)
        w = complex(0.375, 0.2)
        self.assertTrue(x == z)
        self.assertFalse(x != z)
        self.assertFalse(x == w)
        self.assertTrue(x != w)
        for op in operator.lt, operator.le, operator.gt, operator.ge:
            self.assertRaises(TypeError, op, x, z)
            self.assertRaises(TypeError, op, z, x)
            self.assertRaises(TypeError, op, x, w)
            self.assertRaises(TypeError, op, w, x)

    def testMixedEqual(self):
        self.assertTrue(0.5 == F(1, 2))
        self.assertFalse(0.6 == F(1, 2))
        self.assertTrue(F(1, 2) == 0.5)
        self.assertFalse(F(1, 2) == 0.4)
        self.assertTrue(2 == F(4, 2))
        self.assertFalse(2 == F(3, 2))
        self.assertTrue(F(4, 2) == 2)
        self.assertFalse(F(5, 2) == 2)
        self.assertFalse(F(5, 2) == float('nan'))
        self.assertFalse(float('nan') == F(3, 7))
        self.assertFalse(F(5, 2) == float('inf'))
        self.assertFalse(float('-inf') == F(2, 5))

    def testStringification(self):
        self.assertEqual("Fraction(7, 3)", repr(F(7, 3)))
        self.assertEqual("Fraction(6283185307, 2000000000)",
                         repr(F('3.1415926535')))
        self.assertEqual("Fraction(-1, 100000000000000000000)",
                         repr(F(1, -10**20)))
        self.assertEqual("7/3", str(F(7, 3)))
        self.assertEqual("7", str(F(7, 1)))

    def testHash(self):
        hmod = sys.hash_info.modulus
        hinf = sys.hash_info.inf
        self.assertEqual(hash(2.5), hash(F(5, 2)))
        self.assertEqual(hash(10**50), hash(F(10**50)))
        self.assertNotEqual(hash(float(10**23)), hash(F(10**23)))
        self.assertEqual(hinf, hash(F(1, hmod)))
        # Check that __hash__ produces the same value as hash(), for
        # consistency with int and Decimal.  (See issue #10356.)
        self.assertEqual(hash(F(-1)), F(-1).__hash__())

    def testApproximatePi(self):
        # Algorithm borrowed from
        # http://docs.python.org/lib/decimal-recipes.html
        three = F(3)
        lasts, t, s, n, na, d, da = 0, three, 3, 1, 0, 0, 24
        while abs(s - lasts) > F(1, 10**9):
            lasts = s
            n, na = n+na, na+8
            d, da = d+da, da+32
            t = (t * n) / d
            s += t
        self.assertAlmostEqual(math.pi, s)

    def testApproximateCos1(self):
        # Algorithm borrowed from
        # http://docs.python.org/lib/decimal-recipes.html
        x = F(1)
        i, lasts, s, fact, num, sign = 0, 0, F(1), 1, 1, 1
        while abs(s - lasts) > F(1, 10**9):
            lasts = s
            i += 2
            fact *= i * (i-1)
            num *= x * x
            sign *= -1
            s += num / fact * sign
        self.assertAlmostEqual(math.cos(1), s)

    def test_copy_deepcopy_pickle(self):
        r = F(13, 7)
        dr = DummyFraction(13, 7)
        self.assertEqual(r, loads(dumps(r)))
        self.assertEqual(id(r), id(copy(r)))
        self.assertEqual(id(r), id(deepcopy(r)))
        self.assertNotEqual(id(dr), id(copy(dr)))
        self.assertNotEqual(id(dr), id(deepcopy(dr)))
        self.assertTypedEquals(dr, copy(dr))
        self.assertTypedEquals(dr, deepcopy(dr))

    def test_slots(self):
        # Issue 4998
        r = F(13, 7)
        self.assertRaises(AttributeError, setattr, r, 'a', 10)

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