def test_join_missing_element():
    names = [(1, 'one'), (2, 'two'), (3, 'three')]
    fruit = [('apple', 5), ('orange', 1)]

    result = set(starmap(add, join(first, names, second, fruit)))

    expected = set([((1, 'one', 'orange', 1))])

    assert result == expected

def test_join():
    names = [(1, 'one'), (2, 'two'), (3, 'three')]
    fruit = [('apple', 1), ('orange', 1), ('banana', 2), ('coconut', 2)]

    def addpair(pair):
        return pair[0] + pair[1]

    result = set(starmap(add, join(first, names, second, fruit)))

    expected = set([((1, 'one', 'apple', 1)),
                    ((1, 'one', 'orange', 1)),
                    ((2, 'two', 'banana', 2)),
                    ((2, 'two', 'coconut', 2))])

    assert result == expected

    result = set(starmap(add, join(first, names, second, fruit,
                                   left_default=no_default2,
                                   right_default=no_default2)))
    assert result == expected

def test_join_double_repeats():
    names = [(1, 'one'), (2, 'two'), (3, 'three'), (1, 'uno'), (2, 'dos')]
    fruit = [('apple', 1), ('orange', 1), ('banana', 2), ('coconut', 2)]

    result = set(starmap(add, join(first, names, second, fruit)))

    expected = set([((1, 'one', 'apple', 1)),
                    ((1, 'one', 'orange', 1)),
                    ((2, 'two', 'banana', 2)),
                    ((2, 'two', 'coconut', 2)),
                    ((1, 'uno', 'apple', 1)),
                    ((1, 'uno', 'orange', 1)),
                    ((2, 'dos', 'banana', 2)),
                    ((2, 'dos', 'coconut', 2))])

    assert result == expected

def test_key_as_getter():
    squares = [(i, i**2) for i in range(5)]
    pows = [(i, i**2, i**3) for i in range(5)]

    assert set(join(0, squares, 0, pows)) == set(join(lambda x: x[0], squares,
                                                      lambda x: x[0], pows))

    get = lambda x: (x[0], x[1])
    assert set(join([0, 1], squares, [0, 1], pows)) == set(join(get, squares,
                                                                get, pows))

    get = lambda x: (x[0],)
    assert set(join([0], squares, [0], pows)) == set(join(get, squares,
                                                          get, pows))

def test_outer_join():
    result = set(join(identity, [1, 2], identity, [2, 3],
                      left_default=None, right_default=None))
    expected = set([(2, 2), (1, None), (None, 3)])

    assert result == expected