def test_del_node():
from simple_graph import SimpleGraph
new_graph = SimpleGraph()
new_graph.add_edge('A', 'B', 25)
new_graph.add_edge('B', 'A', 10)
new_graph.del_node('A')
assert new_graph.graph == {'B': {}}
def test_sg_del_node_error():
"""Ensure del_node throws IndexError if called with node not in graph."""
from simple_graph import SimpleGraph
test_sg = SimpleGraph()
with pytest.raises(IndexError) as message:
test_sg.del_node("node_a")
assert "That node is not in the graph." in str(message)
def test_sg_del_node():
"""Ensure correct node is deleted, and all its edges are removed."""
from simple_graph import SimpleGraph
test_sg = SimpleGraph()
test_sg.add_edge("a", "c")
test_sg.add_edge("b", "c")
test_sg.add_edge("c", "b")
test_sg.del_node("c")
assert "c" not in test_sg.edges()
def test_del_node_error():
from simple_graph import SimpleGraph
new_graph = SimpleGraph()
with pytest.raises(KeyError):
new_graph.del_node('A')
def test_del_node_edge():
from simple_graph import SimpleGraph
instance = SimpleGraph()
instance.add_edge('waffles', 'waffles2')
instance.del_node('waffles2')
assert instance.graph_dict == {'waffles': {}}
def test_del_node():
from simple_graph import SimpleGraph
instance = SimpleGraph()
instance.add_node("waffles")
instance.del_node('waffles')
assert instance.graph_dict == {}
