import graph_force

def test_list_of_edges():
    edges = [(1, 2), (2, 3), (3, 4), (4, 5), (5, 6)]
    pos = graph_force.layout_from_edge_list(7, edges)
    assert pos is not None
    assert len(pos) == 7


def test_iterator_of_edges():
    pos = graph_force.layout_from_edge_list(
        7,
        ((0, i + 1) for i in range(6))
    )
    assert pos is not None
    assert len(pos) == 7

def test_tuple_of_edges():
    pos = graph_force.layout_from_edge_list(
        7,
        ((0,1), (1,2), (2,3), (3,4), (4,5), (5,6))
    )
    assert pos is not None
    assert len(pos) == 7