| from test.test_support import verbose |
| import random |
| |
| nerrors = 0 |
| |
| def check(tag, expected, raw, compare=None): |
| global nerrors |
| |
| if verbose: |
| print " checking", tag |
| |
| orig = raw[:] # save input in case of error |
| if compare: |
| raw.sort(compare) |
| else: |
| raw.sort() |
| |
| if len(expected) != len(raw): |
| print "error in", tag |
| print "length mismatch;", len(expected), len(raw) |
| print expected |
| print orig |
| print raw |
| nerrors += 1 |
| return |
| |
| for i, good in enumerate(expected): |
| maybe = raw[i] |
| if good is not maybe: |
| print "error in", tag |
| print "out of order at index", i, good, maybe |
| print expected |
| print orig |
| print raw |
| nerrors += 1 |
| return |
| |
| # Try a variety of sizes at and around powers of 2, and at powers of 10. |
| sizes = [0] |
| for power in range(1, 10): |
| n = 2 ** power |
| sizes.extend(range(n-1, n+2)) |
| sizes.extend([10, 100, 1000]) |
| |
| class Complains(object): |
| maybe_complain = True |
| |
| def __init__(self, i): |
| self.i = i |
| |
| def __lt__(self, other): |
| if Complains.maybe_complain and random.random() < 0.001: |
| if verbose: |
| print " complaining at", self, other |
| raise RuntimeError |
| return self.i < other.i |
| |
| def __repr__(self): |
| return "Complains(%d)" % self.i |
| |
| class Stable(object): |
| def __init__(self, key, i): |
| self.key = key |
| self.index = i |
| |
| def __cmp__(self, other): |
| return cmp(self.key, other.key) |
| |
| def __repr__(self): |
| return "Stable(%d, %d)" % (self.key, self.index) |
| |
| for n in sizes: |
| x = range(n) |
| if verbose: |
| print "Testing size", n |
| |
| s = x[:] |
| check("identity", x, s) |
| |
| s = x[:] |
| s.reverse() |
| check("reversed", x, s) |
| |
| s = x[:] |
| random.shuffle(s) |
| check("random permutation", x, s) |
| |
| y = x[:] |
| y.reverse() |
| s = x[:] |
| check("reversed via function", y, s, lambda a, b: cmp(b, a)) |
| |
| if verbose: |
| print " Checking against an insane comparison function." |
| print " If the implementation isn't careful, this may segfault." |
| s = x[:] |
| s.sort(lambda a, b: int(random.random() * 3) - 1) |
| check("an insane function left some permutation", x, s) |
| |
| x = [Complains(i) for i in x] |
| s = x[:] |
| random.shuffle(s) |
| Complains.maybe_complain = True |
| it_complained = False |
| try: |
| s.sort() |
| except RuntimeError: |
| it_complained = True |
| if it_complained: |
| Complains.maybe_complain = False |
| check("exception during sort left some permutation", x, s) |
| |
| s = [Stable(random.randrange(10), i) for i in xrange(n)] |
| augmented = [(e, e.index) for e in s] |
| augmented.sort() # forced stable because ties broken by index |
| x = [e for e, i in augmented] # a stable sort of s |
| check("stability", x, s) |
| |
| if nerrors: |
| print "Test failed", nerrors |
| elif verbose: |
| print "Test passed -- no errors." |