| """Unittests for heapq.""" |
| |
| from heapq import heappush, heappop, heapify, heapreplace, nlargest, nsmallest |
| import random |
| import unittest |
| from test import test_support |
| import sys |
| |
| |
| def heapiter(heap): |
| # An iterator returning a heap's elements, smallest-first. |
| try: |
| while 1: |
| yield heappop(heap) |
| except IndexError: |
| pass |
| |
| class TestHeap(unittest.TestCase): |
| |
| def test_push_pop(self): |
| # 1) Push 256 random numbers and pop them off, verifying all's OK. |
| heap = [] |
| data = [] |
| self.check_invariant(heap) |
| for i in range(256): |
| item = random.random() |
| data.append(item) |
| heappush(heap, item) |
| self.check_invariant(heap) |
| results = [] |
| while heap: |
| item = heappop(heap) |
| self.check_invariant(heap) |
| results.append(item) |
| data_sorted = data[:] |
| data_sorted.sort() |
| self.assertEqual(data_sorted, results) |
| # 2) Check that the invariant holds for a sorted array |
| self.check_invariant(results) |
| |
| self.assertRaises(TypeError, heappush, []) |
| try: |
| self.assertRaises(TypeError, heappush, None, None) |
| self.assertRaises(TypeError, heappop, None) |
| except AttributeError: |
| pass |
| |
| def check_invariant(self, heap): |
| # Check the heap invariant. |
| for pos, item in enumerate(heap): |
| if pos: # pos 0 has no parent |
| parentpos = (pos-1) >> 1 |
| self.assert_(heap[parentpos] <= item) |
| |
| def test_heapify(self): |
| for size in range(30): |
| heap = [random.random() for dummy in range(size)] |
| heapify(heap) |
| self.check_invariant(heap) |
| |
| self.assertRaises(TypeError, heapify, None) |
| |
| def test_naive_nbest(self): |
| data = [random.randrange(2000) for i in range(1000)] |
| heap = [] |
| for item in data: |
| heappush(heap, item) |
| if len(heap) > 10: |
| heappop(heap) |
| heap.sort() |
| self.assertEqual(heap, sorted(data)[-10:]) |
| |
| def test_nbest(self): |
| # Less-naive "N-best" algorithm, much faster (if len(data) is big |
| # enough <wink>) than sorting all of data. However, if we had a max |
| # heap instead of a min heap, it could go faster still via |
| # heapify'ing all of data (linear time), then doing 10 heappops |
| # (10 log-time steps). |
| data = [random.randrange(2000) for i in range(1000)] |
| heap = data[:10] |
| heapify(heap) |
| for item in data[10:]: |
| if item > heap[0]: # this gets rarer the longer we run |
| heapreplace(heap, item) |
| self.assertEqual(list(heapiter(heap)), sorted(data)[-10:]) |
| |
| self.assertRaises(TypeError, heapreplace, None) |
| self.assertRaises(TypeError, heapreplace, None, None) |
| self.assertRaises(IndexError, heapreplace, [], None) |
| |
| def test_heapsort(self): |
| # Exercise everything with repeated heapsort checks |
| for trial in xrange(100): |
| size = random.randrange(50) |
| data = [random.randrange(25) for i in range(size)] |
| if trial & 1: # Half of the time, use heapify |
| heap = data[:] |
| heapify(heap) |
| else: # The rest of the time, use heappush |
| heap = [] |
| for item in data: |
| heappush(heap, item) |
| heap_sorted = [heappop(heap) for i in range(size)] |
| self.assertEqual(heap_sorted, sorted(data)) |
| |
| def test_nsmallest(self): |
| data = [random.randrange(2000) for i in range(1000)] |
| f = lambda x: x * 547 % 2000 |
| for n in (0, 1, 2, 10, 100, 400, 999, 1000, 1100): |
| self.assertEqual(nsmallest(n, data), sorted(data)[:n]) |
| self.assertEqual(nsmallest(n, data, key=f), |
| sorted(data, key=f)[:n]) |
| |
| def test_nlargest(self): |
| data = [random.randrange(2000) for i in range(1000)] |
| f = lambda x: x * 547 % 2000 |
| for n in (0, 1, 2, 10, 100, 400, 999, 1000, 1100): |
| self.assertEqual(nlargest(n, data), sorted(data, reverse=True)[:n]) |
| self.assertEqual(nlargest(n, data, key=f), |
| sorted(data, key=f, reverse=True)[:n]) |
| |
| |
| #============================================================================== |
| |
| class LenOnly: |
| "Dummy sequence class defining __len__ but not __getitem__." |
| def __len__(self): |
| return 10 |
| |
| class GetOnly: |
| "Dummy sequence class defining __getitem__ but not __len__." |
| def __getitem__(self, ndx): |
| return 10 |
| |
| class CmpErr: |
| "Dummy element that always raises an error during comparison" |
| def __cmp__(self, other): |
| raise ZeroDivisionError |
| __eq__ = __ne__ = __lt__ = __le__ = __gt__ = __ge__ = __cmp__ |
| |
| def R(seqn): |
| 'Regular generator' |
| for i in seqn: |
| yield i |
| |
| class G: |
| 'Sequence using __getitem__' |
| def __init__(self, seqn): |
| self.seqn = seqn |
| def __getitem__(self, i): |
| return self.seqn[i] |
| |
| class I: |
| 'Sequence using iterator protocol' |
| def __init__(self, seqn): |
| self.seqn = seqn |
| self.i = 0 |
| def __iter__(self): |
| return self |
| def next(self): |
| if self.i >= len(self.seqn): raise StopIteration |
| v = self.seqn[self.i] |
| self.i += 1 |
| return v |
| |
| class Ig: |
| 'Sequence using iterator protocol defined with a generator' |
| def __init__(self, seqn): |
| self.seqn = seqn |
| self.i = 0 |
| def __iter__(self): |
| for val in self.seqn: |
| yield val |
| |
| class X: |
| 'Missing __getitem__ and __iter__' |
| def __init__(self, seqn): |
| self.seqn = seqn |
| self.i = 0 |
| def next(self): |
| if self.i >= len(self.seqn): raise StopIteration |
| v = self.seqn[self.i] |
| self.i += 1 |
| return v |
| |
| class N: |
| 'Iterator missing next()' |
| def __init__(self, seqn): |
| self.seqn = seqn |
| self.i = 0 |
| def __iter__(self): |
| return self |
| |
| class E: |
| 'Test propagation of exceptions' |
| def __init__(self, seqn): |
| self.seqn = seqn |
| self.i = 0 |
| def __iter__(self): |
| return self |
| def next(self): |
| 3 // 0 |
| |
| class S: |
| 'Test immediate stop' |
| def __init__(self, seqn): |
| pass |
| def __iter__(self): |
| return self |
| def next(self): |
| raise StopIteration |
| |
| from itertools import chain, imap |
| def L(seqn): |
| 'Test multiple tiers of iterators' |
| return chain(imap(lambda x:x, R(Ig(G(seqn))))) |
| |
| class TestErrorHandling(unittest.TestCase): |
| |
| def test_non_sequence(self): |
| for f in (heapify, heappop): |
| self.assertRaises(TypeError, f, 10) |
| for f in (heappush, heapreplace, nlargest, nsmallest): |
| self.assertRaises(TypeError, f, 10, 10) |
| |
| def test_len_only(self): |
| for f in (heapify, heappop): |
| self.assertRaises(TypeError, f, LenOnly()) |
| for f in (heappush, heapreplace): |
| self.assertRaises(TypeError, f, LenOnly(), 10) |
| for f in (nlargest, nsmallest): |
| self.assertRaises(TypeError, f, 2, LenOnly()) |
| |
| def test_get_only(self): |
| for f in (heapify, heappop): |
| self.assertRaises(TypeError, f, GetOnly()) |
| for f in (heappush, heapreplace): |
| self.assertRaises(TypeError, f, GetOnly(), 10) |
| for f in (nlargest, nsmallest): |
| self.assertRaises(TypeError, f, 2, GetOnly()) |
| |
| def test_get_only(self): |
| seq = [CmpErr(), CmpErr(), CmpErr()] |
| for f in (heapify, heappop): |
| self.assertRaises(ZeroDivisionError, f, seq) |
| for f in (heappush, heapreplace): |
| self.assertRaises(ZeroDivisionError, f, seq, 10) |
| for f in (nlargest, nsmallest): |
| self.assertRaises(ZeroDivisionError, f, 2, seq) |
| |
| def test_arg_parsing(self): |
| for f in (heapify, heappop, heappush, heapreplace, nlargest, nsmallest): |
| self.assertRaises(TypeError, f, 10) |
| |
| def test_iterable_args(self): |
| for f in (nlargest, nsmallest): |
| for s in ("123", "", range(1000), (1, 1.2), xrange(2000,2200,5)): |
| for g in (G, I, Ig, L, R): |
| self.assertEqual(f(2, g(s)), f(2,s)) |
| self.assertEqual(f(2, S(s)), []) |
| self.assertRaises(TypeError, f, 2, X(s)) |
| self.assertRaises(TypeError, f, 2, N(s)) |
| self.assertRaises(ZeroDivisionError, f, 2, E(s)) |
| |
| #============================================================================== |
| |
| |
| def test_main(verbose=None): |
| from types import BuiltinFunctionType |
| |
| test_classes = [TestHeap] |
| if isinstance(heapify, BuiltinFunctionType): |
| test_classes.append(TestErrorHandling) |
| test_support.run_unittest(*test_classes) |
| |
| # verify reference counting |
| if verbose and hasattr(sys, "gettotalrefcount"): |
| import gc |
| counts = [None] * 5 |
| for i in xrange(len(counts)): |
| test_support.run_unittest(*test_classes) |
| gc.collect() |
| counts[i] = sys.gettotalrefcount() |
| print counts |
| |
| if __name__ == "__main__": |
| test_main(verbose=True) |