cpython/Lib/test/test_hash.py

46 lines
1.3 KiB
Python

# test the invariant that
# iff a==b then hash(a)==hash(b)
#
import unittest
from test import test_support
class HashEqualityTestCase(unittest.TestCase):
def same_hash(self, *objlist):
# Hash each object given and fail if
# the hash values are not all the same.
hashed = list(map(hash, objlist))
for h in hashed[1:]:
if h != hashed[0]:
self.fail("hashed values differ: %r" % (objlist,))
def test_numeric_literals(self):
self.same_hash(1, 1, 1.0, 1.0+0.0j)
self.same_hash(0, 0.0, 0.0+0.0j)
self.same_hash(-1, -1.0, -1.0+0.0j)
self.same_hash(-2, -2.0, -2.0+0.0j)
def test_coerced_integers(self):
self.same_hash(int(1), int(1), float(1), complex(1),
int('1'), float('1.0'))
self.same_hash(int(-2**31), float(-2**31))
self.same_hash(int(1-2**31), float(1-2**31))
self.same_hash(int(2**31-1), float(2**31-1))
# for 64-bit platforms
self.same_hash(int(2**31), float(2**31))
self.same_hash(int(-2**63), float(-2**63))
def test_coerced_floats(self):
self.same_hash(int(1.23e300), float(1.23e300))
self.same_hash(float(0.5), complex(0.5, 0.0))
def test_main():
test_support.run_unittest(HashEqualityTestCase)
if __name__ == "__main__":
test_main()