projects / OpenSPARC-T2-DV / blame
| Commit | Line | Data |
|---|---|---|
| 86530b38 AT |
1 | import unittest |
| 2 | from test import test_support, seq_tests | |
| 3 | ||
| 4 | class TupleTest(seq_tests.CommonTest): | |
| 5 | type2test = tuple | |
| 6 | ||
| 7 | def test_constructors(self): | |
| 8 | super(TupleTest, self).test_len() | |
| 9 | # calling built-in types without argument must return empty | |
| 10 | self.assertEqual(tuple(), ()) | |
| 11 | ||
| 12 | def test_truth(self): | |
| 13 | super(TupleTest, self).test_truth() | |
| 14 | self.assert_(not ()) | |
| 15 | self.assert_((42, )) | |
| 16 | ||
| 17 | def test_len(self): | |
| 18 | super(TupleTest, self).test_len() | |
| 19 | self.assertEqual(len(()), 0) | |
| 20 | self.assertEqual(len((0,)), 1) | |
| 21 | self.assertEqual(len((0, 1, 2)), 3) | |
| 22 | ||
| 23 | def test_iadd(self): | |
| 24 | super(TupleTest, self).test_iadd() | |
| 25 | u = (0, 1) | |
| 26 | u2 = u | |
| 27 | u += (2, 3) | |
| 28 | self.assert_(u is not u2) | |
| 29 | ||
| 30 | def test_imul(self): | |
| 31 | super(TupleTest, self).test_imul() | |
| 32 | u = (0, 1) | |
| 33 | u2 = u | |
| 34 | u *= 3 | |
| 35 | self.assert_(u is not u2) | |
| 36 | ||
| 37 | def test_tupleresizebug(self): | |
| 38 | # Check that a specific bug in _PyTuple_Resize() is squashed. | |
| 39 | def f(): | |
| 40 | for i in range(1000): | |
| 41 | yield i | |
| 42 | self.assertEqual(list(tuple(f())), range(1000)) | |
| 43 | ||
| 44 | def test_hash(self): | |
| 45 | # See SF bug 942952: Weakness in tuple hash | |
| 46 | # The hash should: | |
| 47 | # be non-commutative | |
| 48 | # should spread-out closely spaced values | |
| 49 | # should not exhibit cancellation in tuples like (x,(x,y)) | |
| 50 | # should be distinct from element hashes: hash(x)!=hash((x,)) | |
| 51 | # This test exercises those cases. | |
| 52 | # For a pure random hash and N=50, the expected number of occupied | |
| 53 | # buckets when tossing 252,600 balls into 2**32 buckets | |
| 54 | # is 252,592.6, or about 7.4 expected collisions. The | |
| 55 | # standard deviation is 2.73. On a box with 64-bit hash | |
| 56 | # codes, no collisions are expected. Here we accept no | |
| 57 | # more than 15 collisions. Any worse and the hash function | |
| 58 | # is sorely suspect. | |
| 59 | ||
| 60 | N=50 | |
| 61 | base = range(N) | |
| 62 | xp = [(i, j) for i in base for j in base] | |
| 63 | inps = base + [(i, j) for i in base for j in xp] + \ | |
| 64 | [(i, j) for i in xp for j in base] + xp + zip(base) | |
| 65 | collisions = len(inps) - len(set(map(hash, inps))) | |
| 66 | self.assert_(collisions <= 15) | |
| 67 | ||
| 68 | def test_repr(self): | |
| 69 | l0 = tuple() | |
| 70 | l2 = (0, 1, 2) | |
| 71 | a0 = self.type2test(l0) | |
| 72 | a2 = self.type2test(l2) | |
| 73 | ||
| 74 | self.assertEqual(str(a0), repr(l0)) | |
| 75 | self.assertEqual(str(a2), repr(l2)) | |
| 76 | self.assertEqual(repr(a0), "()") | |
| 77 | self.assertEqual(repr(a2), "(0, 1, 2)") | |
| 78 | ||
| 79 | def test_main(): | |
| 80 | test_support.run_unittest(TupleTest) | |
| 81 | ||
| 82 | if __name__=="__main__": | |
| 83 | test_main() |