def test_del_edge():
from simple_graph import SimpleGraph
instance = SimpleGraph()
instance.add_edge('waffles', 'waffles2')
instance.add_edge('waffles', 'waffles3')
instance.del_edge('waffles', 'waffles2')
assert instance.graph_dict['waffles'] == {'waffles3': 1}
def test_sg_del_edge():
"""Ensure supplied edge is deleted from appropriate node."""
from simple_graph import SimpleGraph
test_sg = SimpleGraph()
test_sg.add_edge("B", "c")
test_sg.del_edge("B", "c")
assert ("B", "c") not in test_sg.edges()
def test_sg_del_edge_error():
"""Ensure del_edge throws IndexError if called with node not in graph."""
from simple_graph import SimpleGraph
test_sg = SimpleGraph()
test_sg.add_edge("a", "b")
with pytest.raises(IndexError) as message:
test_sg.del_edge("c", "b")
assert "That edge is not in the graph." in str(message)
def test_del_edge_key_error():
from simple_graph import SimpleGraph
new_graph = SimpleGraph()
new_graph.graph = {'A': {'A': 10, 'B': 25}}
with pytest.raises(KeyError):
new_graph.del_edge('G', 'C')
def test_del_edge_val_error():
from simple_graph import SimpleGraph
new_graph = SimpleGraph()
new_graph.graph = {'A': {'A': 10, 'B': 25}}
with pytest.raises(ValueError):
new_graph.del_edge('A', 'E')
def test_del_edge():
from simple_graph import SimpleGraph
new_graph = SimpleGraph()
new_graph.graph = {'A': {'A': 10, 'B': 25}}
new_graph.del_edge('A', 'B')
assert new_graph.graph == {'A': {'A': 10}}
def test_del_non_existent_node2():
from simple_graph import SimpleGraph
instance = SimpleGraph()
instance.add_node("waffles")
with pytest.raises(ValueError):
instance.del_edge('waffles', 'waffles2')
def test_del_non_existent_node1():
from simple_graph import SimpleGraph
instance = SimpleGraph()
with pytest.raises(KeyError):
instance.del_edge('waffles', 'waffles2')
