def test_graph_add_vertex_fail():
grappy = Graph()
with pytest.raises(TypeError) as excinfo:
grappy.add_vertex()
actual = str(excinfo.value)
expected = "add_vertex() missing 1 required positional argument: 'value'"
assert actual == expected
def test_add_node_returns_vertex():
graph = Graph()
vertex = graph.add_node("spam")
assert isinstance(vertex, Vertex)
def test_size_two():
g = Graph()
g.add_node("spam")
g.add_node("eggs")
actual = g.size()
expected = 2
assert actual == expected
def test_graph_get_nodes():
grappy = Graph()
vert_1 = grappy.add_vertex('A')
vert_2 = grappy.add_vertex('B')
actual = str(grappy.get_nodes())
expected = f'dict_keys({[vert_1, vert_2]})'
assert actual == expected
def test_add_edge_no_weight():
g = Graph()
sv = g.add_node("spam")
ev = g.add_node("eggs")
ret_val = g.add_edge(sv, ev)
assert ret_val is None
def test_add_node():
graph = Graph()
expected_value = 'noodle'
actual = graph.add_node('noodle')
assert actual.value == expected_value
def test_not_connected():
g = Graph()
pandora = g.add_node("Pandora")
arendelle = g.add_node("Arendelle")
assert g.connected(pandora, arendelle) is False
assert g.connected(arendelle, pandora) is False
def test_add_node2():
graph = Graph()
graph.add_node("spam")
actual = graph.get_nodes()
expected = 1
assert len(actual) == expected
assert isinstance(actual[0], Vertex)
assert actual[0].value == "spam"
def test_size_empty():
graph = Graph()
expected = 0
actual = graph.size()
assert actual == expected
def test_add_node_return_has_correct_value():
graph = Graph()
expected = "spam" # a vertex's value that comes back
actual = graph.add_node("spam").value
assert actual == expected
def test_get_neighbors_none():
graph = Graph()
banana = graph.add_node("banana")
neighbors = graph.get_neighbors(banana)
assert len(neighbors) == 0
def test_add_edge_interloper_end():
graph = Graph()
end = Vertex("end")
start = graph.add_node("start")
with pytest.raises(KeyError):
graph.add_edge(start, end)
def test_size_one():
graph = Graph()
graph.add_node("spam")
expected = 1
actual = graph.size()
assert actual == expected
def test_depth_traversal_two():
graph = Graph()
city = graph.add_node('Boston')
town = graph.add_node('Seattle')
place = graph.add_node('LA')
graph.add_edge(city, town, 82)
graph.add_edge(town, place, 90)
graph.add_edge(city, place, 42)
actual = depth_traversal(city, graph)
expected = [city, place, town]
assert actual == expected
def test_get_nodes():
g = Graph()
g.add_node("spam")
g.add_node("eggs")
actual = g.get_nodes()
expected = 2
assert len(actual) == expected
assert isinstance(actual[0], Vertex)
assert isinstance(actual[1], Vertex)
assert actual[0].value == "spam"
assert actual[1].value == "eggs"
def test_get_neighbors():
graph = Graph()
eggs = graph.add_node('eggs')
chicken = graph.add_node('chicken')
graph.add_edge(eggs, chicken, 10)
neighbors = graph.get_neighbors(eggs)
assert chicken in neighbors
def test_size_graph():
graph = Graph()
graph.add_node("horse")
graph.add_node("lamb")
actual = graph.size()
expected = 2
assert actual == expected
def test_one_way_connected():
g = Graph()
pandora = g.add_node("Pandora")
arendelle = g.add_node("Arendelle")
g.add_edge(pandora, arendelle)
assert g.connected(pandora, arendelle) is True
assert g.connected(arendelle, pandora) is False
def test_graph_get_neighbors():
grappy = Graph()
vert_1 = grappy.add_vertex('A')
vert_2 = grappy.add_vertex('B')
grappy.add_edge(vert_1, vert_2)
actual = grappy.get_neighbors(vert_1)
expected = [(vert_2, 1)]
assert actual == expected
def test_size_two():
graph = Graph()
graph.add_node("spam")
graph.add_node("bacon")
expected = 2
actual = graph.size()
assert actual == expected
def test_get_nodes():
graph = Graph()
graph.add_node("banana")
graph.add_node("apple")
expected = 2
actual = len(graph.get_nodes())
assert actual == expected
def test_add_edge_sunny():
graph = Graph()
start = graph.add_node("start")
end = graph.add_node("end")
graph.add_edge(start, end)
# no fail means a pass
# can be more explicit if you like
try:
graph.add_edge(start, end)
except KeyError:
pytest.fail("KeyError should not be thrown")
def test_add_edge_with_weight():
graph = Graph()
start = graph.add_node("start")
end = graph.add_node("end")
weight = 10
graph.add_edge(start, end, weight)
def test_get_neighbors_returns_edges_with_custom_weight():
graph = Graph()
banana = graph.add_node("banana")
apple = graph.add_node("apple")
graph.add_edge(apple, banana, 44)
neighbors = graph.get_neighbors(apple)
neighbor_edge = neighbors[0]
assert neighbor_edge.weight == 44
def test_get_n_solo():
g = Graph()
sv = g.add_node("spam")
g.add_edge(sv, sv)
neighbors = g.get_neighbors(sv)
assert len(neighbors) == 1
se = neighbors[0]
assert se.vertex.value == "spam"
assert se.weight == 0
def test_get_neighbors():
g = Graph()
sv = g.add_node("spam")
ev = g.add_node("eggs")
g.add_edge(sv, ev, 5)
neighbors = g.get_neighbors(sv)
assert len(neighbors) == 1
se = neighbors[0]
assert se.vertex.value == "eggs"
assert se.weight == 5
def test_get_neighbors_returns_edges_with_default_weight():
graph = Graph()
banana = graph.add_node("banana")
apple = graph.add_node("apple")
graph.add_edge(apple, banana)
neighbors = graph.get_neighbors(apple)
actual = neighbors[0].weight
expected = 0
assert actual == expected
def test_get_neighbors_returns_edges():
graph = Graph()
banana = graph.add_node("banana")
apple = graph.add_node("apple")
graph.add_edge(apple, banana)
neighbors = graph.get_neighbors(apple)
assert len(neighbors) == 1
neighbor = neighbors[0]
assert isinstance(neighbor, Edge)
assert neighbor.vertex.value == 'banana'
def test_empty_grapgh():
g = Graph()
actual = g.get_vertices()
expected = None
assert actual == expected
def test_one_vertex():
g = Graph()
g.add_vertex('20')
actual = g.get_vertices()
expected = ['20']
assert actual == expected
