def test_add_neigbor():
"""Check the methods add_neighbor and get_neighbours."""
v = Vertex(1, {})
assert not v.get_neighbours()
v2 = Vertex(2, {})
v.add_neighbor(v2, 100)
assert v2 in v.get_neighbours()
def test_get_weight():
"""Check the method get_weight."""
v = Vertex(1, {})
v2 = Vertex(2, {})
v.add_neighbor(v2, 100)
assert v.get_weight(v2) == 100
# v3 is not in any relatioship with v
with pytest.raises(Exception):
v3 = Vertex(3, {})
assert v.get_weight(v3) == 100
def test_string_representation_5():
"""Check special method __str__ for vertices with neighbours."""
v = Vertex(100, {})
v2 = Vertex(2, {})
v.add_neighbor(v2, 200)
s = str(v)
assert s == """
Vertex: 100
Neighbours: [2]
Properties: {}
"""
v3 = Vertex(3, {})
v.add_neighbor(v3, 300)
s = str(v)
assert s == """
Vertex: 100
Neighbours: [2, 3]
Properties: {}
""" or s == """
