def test_valid_with_weights():
name1 = Vertex._make_test_vertex()
name2 = Vertex._make_test_vertex()
s = StringIO("2\n{0}\n{1}\n{0}|{1}|5\n{1}|{0}|2".format(name1, name2))
g = graph_from_file(s)
assert g.size() == 2
assert g.is_connected()
def test_has_cycle_two_vertices_linked():
a = Vertex(Vertex._make_test_vertex())
b = Vertex(Vertex._make_test_vertex())
a.add_edge(Edge(b))
b.add_edge(Edge(a))
g = Graph([a, b])
assert g.has_cycle()
def test_top_sort_cycle():
a = Vertex(Vertex._make_test_vertex())
b = Vertex(Vertex._make_test_vertex())
a.add_edge(Edge(b))
b.add_edge(Edge(a))
g = Graph([a, b])
assert_raises(ValueError, g.top_sort)
def test_extra_pipes():
name1 = Vertex._make_test_vertex()
name2 = Vertex._make_test_vertex()
s = StringIO("2\n{0}\n{1}\n{0}|{1}|5|2\n{1}|{0}|2|5".format(name1, name2))
g = graph_from_file(s)
assert g.size() == 2
assert g.is_connected()
def test_is_connected_two_doubly_connected():
a = Vertex(Vertex._make_test_vertex())
b = Vertex(Vertex._make_test_vertex())
a.add_edge(Edge(b))
b.add_edge(Edge(a))
g = Graph([a, b])
assert g.is_connected()
def test_no_edges():
name1 = Vertex._make_test_vertex()
name2 = Vertex._make_test_vertex()
s = StringIO("2\n{}\n{}".format(name1, name2))
g = graph_from_file(s)
assert g.size() == 2
assert not g.is_connected()
def test_top_sort_chain():
a = Vertex(Vertex._make_test_vertex())
b = Vertex(Vertex._make_test_vertex())
c = Vertex(Vertex._make_test_vertex())
a.add_edge(Edge(b))
b.add_edge(Edge(c))
g = Graph([a, b, c])
assert g.top_sort() == [a, b, c]
def test_find_path_ignores_weights():
a = Vertex(Vertex._make_test_vertex())
b = Vertex(Vertex._make_test_vertex())
a.add_edge(Edge(b, 1))
c = Vertex(Vertex._make_test_vertex())
a.add_edge(Edge(c, 100))
b.add_edge(Edge(c, 1))
assert find_path(a, c) == [a, c]
def test_vertex_valid_edges():
"""Test Vertex creation with a list of already-existing Edges."""
b = Vertex(Vertex._make_test_vertex())
c = Vertex(Vertex._make_test_vertex())
d = Edge(b)
e = Edge(c)
a = Vertex(Vertex._make_test_vertex(), [d, e])
assert a.edges == [d, e]
def test_has_cycle_indirect():
a = Vertex(Vertex._make_test_vertex())
b = Vertex(Vertex._make_test_vertex())
c = Vertex(Vertex._make_test_vertex())
a.add_edge(Edge(b))
b.add_edge(Edge(c))
c.add_edge(Edge(a))
g = Graph([a, b, c])
assert g.has_cycle()
def test_is_connected_three_vert_two_connections():
a = Vertex(Vertex._make_test_vertex())
b = Vertex(Vertex._make_test_vertex())
c = Vertex(Vertex._make_test_vertex())
a.add_edge(Edge(b))
b.add_edge(Edge(c))
c.add_edge(Edge(a))
g = Graph([a, b, c])
assert g.is_connected()
def test_has_cycle_implicit():
"""A Vertex is accessible to the Graph but not explicitly part of it."""
a = Vertex(Vertex._make_test_vertex())
b = Vertex(Vertex._make_test_vertex())
c = Vertex(Vertex._make_test_vertex())
a.add_edge(Edge(b))
b.add_edge(Edge(c))
c.add_edge(Edge(a))
g = Graph([a, b])
assert g.has_cycle()
def test_edge_weight():
a = Vertex(Vertex._make_test_vertex())
b = Edge(a, 10)
assert b.weight == 10
def test_vertex_repr():
s = Vertex._make_test_vertex()
a = Vertex(s)
assert a.__repr__() == "Vertex: {}".format(s)
def test_make_test_vertex():
s = Vertex._make_test_vertex()
a = Vertex(s)
assert a.name == s
def test_graph_duplicate_vertex():
a = Vertex(Vertex._make_test_vertex())
g = Graph([a, a])
assert g.size() == 1
def test_graph_add_new_vertex_new():
a = Vertex(Vertex._make_test_vertex())
g = Graph([a])
g.add_vertex(Vertex(Vertex._make_test_vertex()))
assert g.size() == 2
def test_graph_normal_set():
a = Vertex(Vertex._make_test_vertex())
b = Vertex(Vertex._make_test_vertex())
g = Graph([a, b])
assert g.size() == 2
def test_top_sort_two_single_vertices():
a = Vertex(Vertex._make_test_vertex())
b = Vertex(Vertex._make_test_vertex())
g = Graph([a, b])
assert g.top_sort() in [[a, b], [b, a]]
def test_top_sort_single():
a = Vertex(Vertex._make_test_vertex())
g = Graph([a])
assert g.top_sort() == [a]
def test_is_connected_single():
g = Graph([Vertex(Vertex._make_test_vertex())])
assert g.is_connected()
def test_is_connected_two_single():
a = Vertex(Vertex._make_test_vertex())
b = Vertex(Vertex._make_test_vertex())
g = Graph([a, b])
assert not g.is_connected()
def test_has_cycle_single_no_loop():
a = Vertex(Vertex._make_test_vertex())
g = Graph([a])
assert not g.has_cycle()
def test_has_cycle_self_loop():
a = Vertex(Vertex._make_test_vertex())
a.add_edge(Edge(a))
g = Graph([a])
assert g.has_cycle()
def test_edge_invalid_weight():
a = Vertex(Vertex._make_test_vertex())
assert_raises(ValueError, Edge, a, "test")
def test_top_sort_two_linked_vertices():
a = Vertex(Vertex._make_test_vertex())
b = Vertex(Vertex._make_test_vertex())
a.add_edge(Edge(b))
g = Graph([a, b])
assert g.top_sort() == [a, b]
def test_add_edge_self_loop():
a = Vertex(Vertex._make_test_vertex())
a.add_edge(Edge(a))
assert len(a.edges) == 1
assert a in [e.vertex for e in a.edges]
def test_graph_add_invalid_vertex():
g = Graph([Vertex(Vertex._make_test_vertex())])
assert_raises(TypeError, g.add_vertex, "String name")
def test_size():
g = Graph([Vertex(Vertex._make_test_vertex())])
assert g.size() == len(g.vertices)
def test_is_connected_two_vert_one_edge():
a = Vertex(Vertex._make_test_vertex())
b = Vertex(Vertex._make_test_vertex())
a.add_edge(Edge(b))
g = Graph([a, b])
assert not g.is_connected()