test_iter.py

来自「mallet是自然语言处理、机器学习领域的一个开源项目。」· Python 代码 · 共 785 行 · 第 1/2 页

    # Test map()'s use of iterators.
    def test_builtin_map(self):
        self.assertEqual(map(None, SequenceClass(5)), range(5))
        self.assertEqual(map(lambda x: x+1, SequenceClass(5)), range(1, 6))

        d = {"one": 1, "two": 2, "three": 3}
        self.assertEqual(map(None, d), d.keys())
        self.assertEqual(map(lambda k, d=d: (k, d[k]), d), d.items())
        dkeys = d.keys()
        expected = [(i < len(d) and dkeys[i] or None,
                     i,
                     i < len(d) and dkeys[i] or None)
                    for i in range(5)]
        self.assertEqual(map(None, d,
                                   SequenceClass(5),
                                   iter(d.iterkeys())),
                         expected)

        f = open(TESTFN, "w")
        try:
            for i in range(10):
                f.write("xy" * i + "\n") # line i has len 2*i+1
        finally:
            f.close()
        f = open(TESTFN, "r")
        try:
            self.assertEqual(map(len, f), range(1, 21, 2))
        finally:
            f.close()
            try:
                unlink(TESTFN)
            except OSError:
                pass

    # Test zip()'s use of iterators.
    def test_builtin_zip(self):
        self.assertRaises(TypeError, zip)
        self.assertRaises(TypeError, zip, None)
        self.assertRaises(TypeError, zip, range(10), 42)
        self.assertRaises(TypeError, zip, range(10), zip)

        self.assertEqual(zip(IteratingSequenceClass(3)),
                         [(0,), (1,), (2,)])
        self.assertEqual(zip(SequenceClass(3)),
                         [(0,), (1,), (2,)])

        d = {"one": 1, "two": 2, "three": 3}
        self.assertEqual(d.items(), zip(d, d.itervalues()))

        # Generate all ints starting at constructor arg.
        class IntsFrom:
            def __init__(self, start):
                self.i = start

            def __iter__(self):
                return self

            def next(self):
                i = self.i
                self.i = i+1
                return i

        f = open(TESTFN, "w")
        try:
            f.write("a\n" "bbb\n" "cc\n")
        finally:
            f.close()
        f = open(TESTFN, "r")
        try:
            self.assertEqual(zip(IntsFrom(0), f, IntsFrom(-100)),
                             [(0, "a\n", -100),
                              (1, "bbb\n", -99),
                              (2, "cc\n", -98)])
        finally:
            f.close()
            try:
                unlink(TESTFN)
            except OSError:
                pass

    # Test reduces()'s use of iterators.
    def test_builtin_reduce(self):
        from operator import add
        self.assertEqual(reduce(add, SequenceClass(5)), 10)
        self.assertEqual(reduce(add, SequenceClass(5), 42), 52)
        self.assertRaises(TypeError, reduce, add, SequenceClass(0))
        self.assertEqual(reduce(add, SequenceClass(0), 42), 42)
        self.assertEqual(reduce(add, SequenceClass(1)), 0)
        self.assertEqual(reduce(add, SequenceClass(1), 42), 42)

        d = {"one": 1, "two": 2, "three": 3}
        self.assertEqual(reduce(add, d), "".join(d.keys()))

    # This test case will be removed if we don't have Unicode
    def test_unicode_join_endcase(self):

        # This class inserts a Unicode object into its argument's natural
        # iteration, in the 3rd position.
        class OhPhooey:
            def __init__(self, seq):
                self.it = iter(seq)
                self.i = 0

            def __iter__(self):
                return self

            def next(self):
                i = self.i
                self.i = i+1
                if i == 2:
                    return unicode("fooled you!")
                return self.it.next()

        f = open(TESTFN, "w")
        try:
            f.write("a\n" + "b\n" + "c\n")
        finally:
            f.close()

        f = open(TESTFN, "r")
        # Nasty:  string.join(s) can't know whether unicode.join() is needed
        # until it's seen all of s's elements.  But in this case, f's
        # iterator cannot be restarted.  So what we're testing here is
        # whether string.join() can manage to remember everything it's seen
        # and pass that on to unicode.join().
        try:
            got = " - ".join(OhPhooey(f))
            self.assertEqual(got, unicode("a\n - b\n - fooled you! - c\n"))
        finally:
            f.close()
            try:
                unlink(TESTFN)
            except OSError:
                pass
    if not have_unicode:
        def test_unicode_join_endcase(self): pass

    # Test iterators with 'x in y' and 'x not in y'.
    def test_in_and_not_in(self):
        for sc5 in IteratingSequenceClass(5), SequenceClass(5):
            for i in range(5):
                self.assert_(i in sc5)
            for i in "abc", -1, 5, 42.42, (3, 4), [], {1: 1}, 3-12j, sc5:
                self.assert_(i not in sc5)

        self.assertRaises(TypeError, lambda: 3 in 12)
        self.assertRaises(TypeError, lambda: 3 not in map)

        d = {"one": 1, "two": 2, "three": 3, 1j: 2j}
        for k in d:
            self.assert_(k in d)
            self.assert_(k not in d.itervalues())
        for v in d.values():
            self.assert_(v in d.itervalues())
            self.assert_(v not in d)
        for k, v in d.iteritems():
            self.assert_((k, v) in d.iteritems())
            self.assert_((v, k) not in d.iteritems())

        f = open(TESTFN, "w")
        try:
            f.write("a\n" "b\n" "c\n")
        finally:
            f.close()
        f = open(TESTFN, "r")
        try:
            for chunk in "abc":
                f.seek(0, 0)
                self.assert_(chunk not in f)
                f.seek(0, 0)
                self.assert_((chunk + "\n") in f)
        finally:
            f.close()
            try:
                unlink(TESTFN)
            except OSError:
                pass

    # Test iterators with operator.countOf (PySequence_Count).
    def test_countOf(self):
        from operator import countOf
        self.assertEqual(countOf([1,2,2,3,2,5], 2), 3)
        self.assertEqual(countOf((1,2,2,3,2,5), 2), 3)
        self.assertEqual(countOf("122325", "2"), 3)
        self.assertEqual(countOf("122325", "6"), 0)

        self.assertRaises(TypeError, countOf, 42, 1)
        self.assertRaises(TypeError, countOf, countOf, countOf)

        d = {"one": 3, "two": 3, "three": 3, 1j: 2j}
        for k in d:
            self.assertEqual(countOf(d, k), 1)
        self.assertEqual(countOf(d.itervalues(), 3), 3)
        self.assertEqual(countOf(d.itervalues(), 2j), 1)
        self.assertEqual(countOf(d.itervalues(), 1j), 0)

        f = open(TESTFN, "w")
        try:
            f.write("a\n" "b\n" "c\n" "b\n")
        finally:
            f.close()
        f = open(TESTFN, "r")
        try:
            for letter, count in ("a", 1), ("b", 2), ("c", 1), ("d", 0):
                f.seek(0, 0)
                self.assertEqual(countOf(f, letter + "\n"), count)
        finally:
            f.close()
            try:
                unlink(TESTFN)
            except OSError:
                pass

    # Test iterators with operator.indexOf (PySequence_Index).
    def test_indexOf(self):
        from operator import indexOf
        self.assertEqual(indexOf([1,2,2,3,2,5], 1), 0)
        self.assertEqual(indexOf((1,2,2,3,2,5), 2), 1)
        self.assertEqual(indexOf((1,2,2,3,2,5), 3), 3)
        self.assertEqual(indexOf((1,2,2,3,2,5), 5), 5)
        self.assertRaises(ValueError, indexOf, (1,2,2,3,2,5), 0)
        self.assertRaises(ValueError, indexOf, (1,2,2,3,2,5), 6)

        self.assertEqual(indexOf("122325", "2"), 1)
        self.assertEqual(indexOf("122325", "5"), 5)
        self.assertRaises(ValueError, indexOf, "122325", "6")

        self.assertRaises(TypeError, indexOf, 42, 1)
        self.assertRaises(TypeError, indexOf, indexOf, indexOf)

        f = open(TESTFN, "w")
        try:
            f.write("a\n" "b\n" "c\n" "d\n" "e\n")
        finally:
            f.close()
        f = open(TESTFN, "r")
        try:
            fiter = iter(f)
            self.assertEqual(indexOf(fiter, "b\n"), 1)
            self.assertEqual(indexOf(fiter, "d\n"), 1)
            self.assertEqual(indexOf(fiter, "e\n"), 0)
            self.assertRaises(ValueError, indexOf, fiter, "a\n")
        finally:
            f.close()
            try:
                unlink(TESTFN)
            except OSError:
                pass

        iclass = IteratingSequenceClass(3)
        for i in range(3):
            self.assertEqual(indexOf(iclass, i), i)
        self.assertRaises(ValueError, indexOf, iclass, -1)

    # Test iterators with file.writelines().
    def test_writelines(self):
        f = file(TESTFN, "w")

        try:
            self.assertRaises(TypeError, f.writelines, None)
            self.assertRaises(TypeError, f.writelines, 42)

            f.writelines(["1\n", "2\n"])
            f.writelines(("3\n", "4\n"))
            f.writelines({'5\n': None})
            f.writelines({})

            # Try a big chunk too.
            class Iterator:
                def __init__(self, start, finish):
                    self.start = start
                    self.finish = finish
                    self.i = self.start

                def next(self):
                    if self.i >= self.finish:
                        raise StopIteration
                    result = str(self.i) + '\n'
                    self.i += 1
                    return result

                def __iter__(self):
                    return self

            class Whatever:
                def __init__(self, start, finish):
                    self.start = start
                    self.finish = finish

                def __iter__(self):
                    return Iterator(self.start, self.finish)

            f.writelines(Whatever(6, 6+2000))
            f.close()

            f = file(TESTFN)
            expected = [str(i) + "\n" for i in range(1, 2006)]
            self.assertEqual(list(f), expected)

        finally:
            f.close()
            try:
                unlink(TESTFN)
            except OSError:
                pass


    # Test iterators on RHS of unpacking assignments.
    def test_unpack_iter(self):
        a, b = 1, 2
        self.assertEqual((a, b), (1, 2))

        a, b, c = IteratingSequenceClass(3)
        self.assertEqual((a, b, c), (0, 1, 2))

        try:    # too many values
            a, b = IteratingSequenceClass(3)
        except ValueError:
            pass
        else:
            self.fail("should have raised ValueError")

        try:    # not enough values
            a, b, c = IteratingSequenceClass(2)
        except ValueError:
            pass
        else:
            self.fail("should have raised ValueError")

        try:    # not iterable
            a, b, c = len
        except TypeError:
            pass
        else:
            self.fail("should have raised TypeError")

        a, b, c = {1: 42, 2: 42, 3: 42}.itervalues()
        self.assertEqual((a, b, c), (42, 42, 42))

        f = open(TESTFN, "w")
        lines = ("a\n", "bb\n", "ccc\n")
        try:
            for line in lines:
                f.write(line)
        finally:
            f.close()
        f = open(TESTFN, "r")
        try:
            a, b, c = f
            self.assertEqual((a, b, c), lines)
        finally:
            f.close()
            try:
                unlink(TESTFN)
            except OSError:
                pass

        (a, b), (c,) = IteratingSequenceClass(2), {42: 24}
        self.assertEqual((a, b, c), (0, 1, 42))

        # Test reference count behavior

        class C(object):
            count = 0
            def __new__(cls):
                cls.count += 1
                return object.__new__(cls)
            def __del__(self):
                cls = self.__class__
                assert cls.count > 0
                cls.count -= 1
        #x = C()
        #self.assertEqual(C.count, 1)
        #del x
        #self.assertEqual(C.count, 0)
        #l = [C(), C(), C()]
        #self.assertEqual(C.count, 3)
        #try:
        #    a, b = iter(l)
        #except ValueError:
        #    pass
        #del l
        #self.assertEqual(C.count, 0)

def test_main():
    run_unittest(TestCase)


if __name__ == "__main__":
    test_main()