def test_has_node():
    """edge added, new node added"""
    g = SimpleGraph()
    g.add_node('a')
    g.add_node('b')
    g.add_node('c')
    g.add_edge('a', 'c')
    g.add_edge('a', 'b')
    assert g.has_node('b')
def test_has_node():
    """edge added, new node added"""
    g = SimpleGraph()
    g.add_node('a')
    g.add_node('b')
    g.add_node('c')
    g.add_edge('a', 'c')
    g.add_edge('a', 'b')
    assert g.has_node('b')
def test_add_edge():
    """edge added, new node added"""
    g = SimpleGraph()
    g.add_node('a')
    g.add_node('b')
    g.add_node('c')
    g.add_edge('a', 'c')
    g.add_edge('a', 'b')
    g.add_edge('q', 'a')
    assert g.has_node('q')
    assert g.neighbors('q') == {'a': 0}
def test_del_nodes():
    """nodes are deleted"""
    g = SimpleGraph()
    g.add_node('a')
    g.add_node('b')
    g.add_node('c')
    g.add_edge('a', 'c')
    g.add_edge('a', 'b')
    g.del_node('a')
    assert 'a' not in g.nodes()
    assert g.has_node('a') is False
def test_add_edge():
    """edge added, new node added"""
    g = SimpleGraph()
    g.add_node('a')
    g.add_node('b')
    g.add_node('c')
    g.add_edge('a', 'c')
    g.add_edge('a', 'b')
    g.add_edge('q', 'a')
    assert g.has_node('q')
    assert g.neighbors('q') == {'a': 0}
def test_del_nodes():
    """nodes are deleted"""
    g = SimpleGraph()
    g.add_node('a')
    g.add_node('b')
    g.add_node('c')
    g.add_edge('a', 'c')
    g.add_edge('a', 'b')
    g.del_node('a')
    assert 'a' not in g.nodes()
    assert g.has_node('a') is False