def test_distances() -> None:
a_cell = Cell(0, 0)
another_cell = Cell(0, 1)
yet_another_cell = Cell(0, 2)
a_cell.east = another_cell
a_cell += another_cell
another_cell.east = yet_another_cell
another_cell += yet_another_cell
distances = a_cell.distances
assert set(distances.cells) == {yet_another_cell, another_cell, a_cell}
assert distances[a_cell] == 0
assert distances[another_cell] == 1
assert distances[yet_another_cell] == 2
def test_has_neighbors() -> None:
a_cell = Cell(1, 1)
another_cell = Cell(1, 2)
yet_another_cell = Cell(2, 1)
a_cell.north = another_cell
another_cell.south = yet_another_cell
yet_another_cell.east = another_cell
yet_another_cell.west = a_cell
assert another_cell in a_cell.neighbors
assert yet_another_cell not in a_cell.neighbors
assert len(a_cell.neighbors) == 1
assert a_cell not in another_cell.neighbors
assert yet_another_cell in another_cell.neighbors
assert len(another_cell.neighbors) == 1
assert a_cell in yet_another_cell.neighbors
assert another_cell in yet_another_cell.neighbors
assert len(yet_another_cell.neighbors) == 2