| # test interactions between int, float, Decimal and Fraction |
| |
| import unittest |
| import random |
| import math |
| import sys |
| import operator |
| |
| from decimal import Decimal as D |
| from fractions import Fraction as F |
| |
| # Constants related to the hash implementation; hash(x) is based |
| # on the reduction of x modulo the prime _PyHASH_MODULUS. |
| _PyHASH_MODULUS = sys.hash_info.modulus |
| _PyHASH_INF = sys.hash_info.inf |
| |
| class HashTest(unittest.TestCase): |
| def check_equal_hash(self, x, y): |
| # check both that x and y are equal and that their hashes are equal |
| self.assertEqual(hash(x), hash(y), |
| "got different hashes for {!r} and {!r}".format(x, y)) |
| self.assertEqual(x, y) |
| |
| def test_bools(self): |
| self.check_equal_hash(False, 0) |
| self.check_equal_hash(True, 1) |
| |
| def test_integers(self): |
| # check that equal values hash equal |
| |
| # exact integers |
| for i in range(-1000, 1000): |
| self.check_equal_hash(i, float(i)) |
| self.check_equal_hash(i, D(i)) |
| self.check_equal_hash(i, F(i)) |
| |
| # the current hash is based on reduction modulo 2**n-1 for some |
| # n, so pay special attention to numbers of the form 2**n and 2**n-1. |
| for i in range(100): |
| n = 2**i - 1 |
| if n == int(float(n)): |
| self.check_equal_hash(n, float(n)) |
| self.check_equal_hash(-n, -float(n)) |
| self.check_equal_hash(n, D(n)) |
| self.check_equal_hash(n, F(n)) |
| self.check_equal_hash(-n, D(-n)) |
| self.check_equal_hash(-n, F(-n)) |
| |
| n = 2**i |
| self.check_equal_hash(n, float(n)) |
| self.check_equal_hash(-n, -float(n)) |
| self.check_equal_hash(n, D(n)) |
| self.check_equal_hash(n, F(n)) |
| self.check_equal_hash(-n, D(-n)) |
| self.check_equal_hash(-n, F(-n)) |
| |
| # random values of various sizes |
| for _ in range(1000): |
| e = random.randrange(300) |
| n = random.randrange(-10**e, 10**e) |
| self.check_equal_hash(n, D(n)) |
| self.check_equal_hash(n, F(n)) |
| if n == int(float(n)): |
| self.check_equal_hash(n, float(n)) |
| |
| def test_binary_floats(self): |
| # check that floats hash equal to corresponding Fractions and Decimals |
| |
| # floats that are distinct but numerically equal should hash the same |
| self.check_equal_hash(0.0, -0.0) |
| |
| # zeros |
| self.check_equal_hash(0.0, D(0)) |
| self.check_equal_hash(-0.0, D(0)) |
| self.check_equal_hash(-0.0, D('-0.0')) |
| self.check_equal_hash(0.0, F(0)) |
| |
| # infinities and nans |
| self.check_equal_hash(float('inf'), D('inf')) |
| self.check_equal_hash(float('-inf'), D('-inf')) |
| |
| for _ in range(1000): |
| x = random.random() * math.exp(random.random()*200.0 - 100.0) |
| self.check_equal_hash(x, D.from_float(x)) |
| self.check_equal_hash(x, F.from_float(x)) |
| |
| def test_complex(self): |
| # complex numbers with zero imaginary part should hash equal to |
| # the corresponding float |
| |
| test_values = [0.0, -0.0, 1.0, -1.0, 0.40625, -5136.5, |
| float('inf'), float('-inf')] |
| |
| for zero in -0.0, 0.0: |
| for value in test_values: |
| self.check_equal_hash(value, complex(value, zero)) |
| |
| def test_decimals(self): |
| # check that Decimal instances that have different representations |
| # but equal values give the same hash |
| zeros = ['0', '-0', '0.0', '-0.0e10', '000e-10'] |
| for zero in zeros: |
| self.check_equal_hash(D(zero), D(0)) |
| |
| self.check_equal_hash(D('1.00'), D(1)) |
| self.check_equal_hash(D('1.00000'), D(1)) |
| self.check_equal_hash(D('-1.00'), D(-1)) |
| self.check_equal_hash(D('-1.00000'), D(-1)) |
| self.check_equal_hash(D('123e2'), D(12300)) |
| self.check_equal_hash(D('1230e1'), D(12300)) |
| self.check_equal_hash(D('12300'), D(12300)) |
| self.check_equal_hash(D('12300.0'), D(12300)) |
| self.check_equal_hash(D('12300.00'), D(12300)) |
| self.check_equal_hash(D('12300.000'), D(12300)) |
| |
| def test_fractions(self): |
| # check special case for fractions where either the numerator |
| # or the denominator is a multiple of _PyHASH_MODULUS |
| self.assertEqual(hash(F(1, _PyHASH_MODULUS)), _PyHASH_INF) |
| self.assertEqual(hash(F(-1, 3*_PyHASH_MODULUS)), -_PyHASH_INF) |
| self.assertEqual(hash(F(7*_PyHASH_MODULUS, 1)), 0) |
| self.assertEqual(hash(F(-_PyHASH_MODULUS, 1)), 0) |
| |
| def test_hash_normalization(self): |
| # Test for a bug encountered while changing long_hash. |
| # |
| # Given objects x and y, it should be possible for y's |
| # __hash__ method to return hash(x) in order to ensure that |
| # hash(x) == hash(y). But hash(x) is not exactly equal to the |
| # result of x.__hash__(): there's some internal normalization |
| # to make sure that the result fits in a C long, and is not |
| # equal to the invalid hash value -1. This internal |
| # normalization must therefore not change the result of |
| # hash(x) for any x. |
| |
| class HalibutProxy: |
| def __hash__(self): |
| return hash('halibut') |
| def __eq__(self, other): |
| return other == 'halibut' |
| |
| x = {'halibut', HalibutProxy()} |
| self.assertEqual(len(x), 1) |
| |
| class ComparisonTest(unittest.TestCase): |
| def test_mixed_comparisons(self): |
| |
| # ordered list of distinct test values of various types: |
| # int, float, Fraction, Decimal |
| test_values = [ |
| float('-inf'), |
| D('-1e425000000'), |
| -1e308, |
| F(-22, 7), |
| -3.14, |
| -2, |
| 0.0, |
| 1e-320, |
| True, |
| F('1.2'), |
| D('1.3'), |
| float('1.4'), |
| F(275807, 195025), |
| D('1.414213562373095048801688724'), |
| F(114243, 80782), |
| F(473596569, 84615), |
| 7e200, |
| D('infinity'), |
| ] |
| for i, first in enumerate(test_values): |
| for second in test_values[i+1:]: |
| self.assertLess(first, second) |
| self.assertLessEqual(first, second) |
| self.assertGreater(second, first) |
| self.assertGreaterEqual(second, first) |
| |
| def test_complex(self): |
| # comparisons with complex are special: equality and inequality |
| # comparisons should always succeed, but order comparisons should |
| # raise TypeError. |
| z = 1.0 + 0j |
| w = -3.14 + 2.7j |
| |
| for v in 1, 1.0, F(1), D(1), complex(1): |
| self.assertEqual(z, v) |
| self.assertEqual(v, z) |
| |
| for v in 2, 2.0, F(2), D(2), complex(2): |
| self.assertNotEqual(z, v) |
| self.assertNotEqual(v, z) |
| self.assertNotEqual(w, v) |
| self.assertNotEqual(v, w) |
| |
| for v in (1, 1.0, F(1), D(1), complex(1), |
| 2, 2.0, F(2), D(2), complex(2), w): |
| for op in operator.le, operator.lt, operator.ge, operator.gt: |
| self.assertRaises(TypeError, op, z, v) |
| self.assertRaises(TypeError, op, v, z) |
| |
| |
| if __name__ == '__main__': |
| unittest.main() |