ai-content-maker/.venv/Lib/site-packages/networkx/classes/tests/test_graph.py

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2024-05-03 04:18:51 +03:00
import gc
import pickle
import platform
import pytest
import networkx as nx
from networkx.utils import edges_equal, graphs_equal, nodes_equal
class BaseGraphTester:
"""Tests for data-structure independent graph class features."""
def test_contains(self):
G = self.K3
assert 1 in G
assert 4 not in G
assert "b" not in G
assert [] not in G # no exception for nonhashable
assert {1: 1} not in G # no exception for nonhashable
def test_order(self):
G = self.K3
assert len(G) == 3
assert G.order() == 3
assert G.number_of_nodes() == 3
def test_nodes(self):
G = self.K3
assert isinstance(G._node, G.node_dict_factory)
assert isinstance(G._adj, G.adjlist_outer_dict_factory)
assert all(
isinstance(adj, G.adjlist_inner_dict_factory) for adj in G._adj.values()
)
assert sorted(G.nodes()) == self.k3nodes
assert sorted(G.nodes(data=True)) == [(0, {}), (1, {}), (2, {})]
def test_none_node(self):
G = self.Graph()
with pytest.raises(ValueError):
G.add_node(None)
with pytest.raises(ValueError):
G.add_nodes_from([None])
with pytest.raises(ValueError):
G.add_edge(0, None)
with pytest.raises(ValueError):
G.add_edges_from([(0, None)])
def test_has_node(self):
G = self.K3
assert G.has_node(1)
assert not G.has_node(4)
assert not G.has_node([]) # no exception for nonhashable
assert not G.has_node({1: 1}) # no exception for nonhashable
def test_has_edge(self):
G = self.K3
assert G.has_edge(0, 1)
assert not G.has_edge(0, -1)
def test_neighbors(self):
G = self.K3
assert sorted(G.neighbors(0)) == [1, 2]
with pytest.raises(nx.NetworkXError):
G.neighbors(-1)
@pytest.mark.skipif(
platform.python_implementation() == "PyPy", reason="PyPy gc is different"
)
def test_memory_leak(self):
G = self.Graph()
def count_objects_of_type(_type):
return sum(1 for obj in gc.get_objects() if isinstance(obj, _type))
gc.collect()
before = count_objects_of_type(self.Graph)
G.copy()
gc.collect()
after = count_objects_of_type(self.Graph)
assert before == after
# test a subgraph of the base class
class MyGraph(self.Graph):
pass
gc.collect()
G = MyGraph()
before = count_objects_of_type(MyGraph)
G.copy()
gc.collect()
after = count_objects_of_type(MyGraph)
assert before == after
def test_edges(self):
G = self.K3
assert isinstance(G._adj, G.adjlist_outer_dict_factory)
assert edges_equal(G.edges(), [(0, 1), (0, 2), (1, 2)])
assert edges_equal(G.edges(0), [(0, 1), (0, 2)])
assert edges_equal(G.edges([0, 1]), [(0, 1), (0, 2), (1, 2)])
with pytest.raises(nx.NetworkXError):
G.edges(-1)
def test_degree(self):
G = self.K3
assert sorted(G.degree()) == [(0, 2), (1, 2), (2, 2)]
assert dict(G.degree()) == {0: 2, 1: 2, 2: 2}
assert G.degree(0) == 2
with pytest.raises(nx.NetworkXError):
G.degree(-1) # node not in graph
def test_size(self):
G = self.K3
assert G.size() == 3
assert G.number_of_edges() == 3
def test_nbunch_iter(self):
G = self.K3
assert nodes_equal(G.nbunch_iter(), self.k3nodes) # all nodes
assert nodes_equal(G.nbunch_iter(0), [0]) # single node
assert nodes_equal(G.nbunch_iter([0, 1]), [0, 1]) # sequence
# sequence with none in graph
assert nodes_equal(G.nbunch_iter([-1]), [])
# string sequence with none in graph
assert nodes_equal(G.nbunch_iter("foo"), [])
# node not in graph doesn't get caught upon creation of iterator
bunch = G.nbunch_iter(-1)
# but gets caught when iterator used
with pytest.raises(nx.NetworkXError, match="is not a node or a sequence"):
list(bunch)
# unhashable doesn't get caught upon creation of iterator
bunch = G.nbunch_iter([0, 1, 2, {}])
# but gets caught when iterator hits the unhashable
with pytest.raises(
nx.NetworkXError, match="in sequence nbunch is not a valid node"
):
list(bunch)
def test_nbunch_iter_node_format_raise(self):
# Tests that a node that would have failed string formatting
# doesn't cause an error when attempting to raise a
# :exc:`nx.NetworkXError`.
# For more information, see pull request #1813.
G = self.Graph()
nbunch = [("x", set())]
with pytest.raises(nx.NetworkXError):
list(G.nbunch_iter(nbunch))
def test_selfloop_degree(self):
G = self.Graph()
G.add_edge(1, 1)
assert sorted(G.degree()) == [(1, 2)]
assert dict(G.degree()) == {1: 2}
assert G.degree(1) == 2
assert sorted(G.degree([1])) == [(1, 2)]
assert G.degree(1, weight="weight") == 2
def test_selfloops(self):
G = self.K3.copy()
G.add_edge(0, 0)
assert nodes_equal(nx.nodes_with_selfloops(G), [0])
assert edges_equal(nx.selfloop_edges(G), [(0, 0)])
assert nx.number_of_selfloops(G) == 1
G.remove_edge(0, 0)
G.add_edge(0, 0)
G.remove_edges_from([(0, 0)])
G.add_edge(1, 1)
G.remove_node(1)
G.add_edge(0, 0)
G.add_edge(1, 1)
G.remove_nodes_from([0, 1])
def test_cache_reset(self):
G = self.K3.copy()
old_adj = G.adj
assert id(G.adj) == id(old_adj)
G._adj = {}
assert id(G.adj) != id(old_adj)
old_nodes = G.nodes
assert id(G.nodes) == id(old_nodes)
G._node = {}
assert id(G.nodes) != id(old_nodes)
def test_attributes_cached(self):
G = self.K3.copy()
assert id(G.nodes) == id(G.nodes)
assert id(G.edges) == id(G.edges)
assert id(G.degree) == id(G.degree)
assert id(G.adj) == id(G.adj)
class BaseAttrGraphTester(BaseGraphTester):
"""Tests of graph class attribute features."""
def test_weighted_degree(self):
G = self.Graph()
G.add_edge(1, 2, weight=2, other=3)
G.add_edge(2, 3, weight=3, other=4)
assert sorted(d for n, d in G.degree(weight="weight")) == [2, 3, 5]
assert dict(G.degree(weight="weight")) == {1: 2, 2: 5, 3: 3}
assert G.degree(1, weight="weight") == 2
assert nodes_equal((G.degree([1], weight="weight")), [(1, 2)])
assert nodes_equal((d for n, d in G.degree(weight="other")), [3, 7, 4])
assert dict(G.degree(weight="other")) == {1: 3, 2: 7, 3: 4}
assert G.degree(1, weight="other") == 3
assert edges_equal((G.degree([1], weight="other")), [(1, 3)])
def add_attributes(self, G):
G.graph["foo"] = []
G.nodes[0]["foo"] = []
G.remove_edge(1, 2)
ll = []
G.add_edge(1, 2, foo=ll)
G.add_edge(2, 1, foo=ll)
def test_name(self):
G = self.Graph(name="")
assert G.name == ""
G = self.Graph(name="test")
assert G.name == "test"
def test_str_unnamed(self):
G = self.Graph()
G.add_edges_from([(1, 2), (2, 3)])
assert str(G) == f"{type(G).__name__} with 3 nodes and 2 edges"
def test_str_named(self):
G = self.Graph(name="foo")
G.add_edges_from([(1, 2), (2, 3)])
assert str(G) == f"{type(G).__name__} named 'foo' with 3 nodes and 2 edges"
def test_graph_chain(self):
G = self.Graph([(0, 1), (1, 2)])
DG = G.to_directed(as_view=True)
SDG = DG.subgraph([0, 1])
RSDG = SDG.reverse(copy=False)
assert G is DG._graph
assert DG is SDG._graph
assert SDG is RSDG._graph
def test_copy(self):
G = self.Graph()
G.add_node(0)
G.add_edge(1, 2)
self.add_attributes(G)
# copy edge datadict but any container attr are same
H = G.copy()
self.graphs_equal(H, G)
self.different_attrdict(H, G)
self.shallow_copy_attrdict(H, G)
def test_class_copy(self):
G = self.Graph()
G.add_node(0)
G.add_edge(1, 2)
self.add_attributes(G)
# copy edge datadict but any container attr are same
H = G.__class__(G)
self.graphs_equal(H, G)
self.different_attrdict(H, G)
self.shallow_copy_attrdict(H, G)
def test_fresh_copy(self):
G = self.Graph()
G.add_node(0)
G.add_edge(1, 2)
self.add_attributes(G)
# copy graph structure but use fresh datadict
H = G.__class__()
H.add_nodes_from(G)
H.add_edges_from(G.edges())
assert len(G.nodes[0]) == 1
ddict = G.adj[1][2][0] if G.is_multigraph() else G.adj[1][2]
assert len(ddict) == 1
assert len(H.nodes[0]) == 0
ddict = H.adj[1][2][0] if H.is_multigraph() else H.adj[1][2]
assert len(ddict) == 0
def is_deepcopy(self, H, G):
self.graphs_equal(H, G)
self.different_attrdict(H, G)
self.deep_copy_attrdict(H, G)
def deep_copy_attrdict(self, H, G):
self.deepcopy_graph_attr(H, G)
self.deepcopy_node_attr(H, G)
self.deepcopy_edge_attr(H, G)
def deepcopy_graph_attr(self, H, G):
assert G.graph["foo"] == H.graph["foo"]
G.graph["foo"].append(1)
assert G.graph["foo"] != H.graph["foo"]
def deepcopy_node_attr(self, H, G):
assert G.nodes[0]["foo"] == H.nodes[0]["foo"]
G.nodes[0]["foo"].append(1)
assert G.nodes[0]["foo"] != H.nodes[0]["foo"]
def deepcopy_edge_attr(self, H, G):
assert G[1][2]["foo"] == H[1][2]["foo"]
G[1][2]["foo"].append(1)
assert G[1][2]["foo"] != H[1][2]["foo"]
def is_shallow_copy(self, H, G):
self.graphs_equal(H, G)
self.shallow_copy_attrdict(H, G)
def shallow_copy_attrdict(self, H, G):
self.shallow_copy_graph_attr(H, G)
self.shallow_copy_node_attr(H, G)
self.shallow_copy_edge_attr(H, G)
def shallow_copy_graph_attr(self, H, G):
assert G.graph["foo"] == H.graph["foo"]
G.graph["foo"].append(1)
assert G.graph["foo"] == H.graph["foo"]
def shallow_copy_node_attr(self, H, G):
assert G.nodes[0]["foo"] == H.nodes[0]["foo"]
G.nodes[0]["foo"].append(1)
assert G.nodes[0]["foo"] == H.nodes[0]["foo"]
def shallow_copy_edge_attr(self, H, G):
assert G[1][2]["foo"] == H[1][2]["foo"]
G[1][2]["foo"].append(1)
assert G[1][2]["foo"] == H[1][2]["foo"]
def same_attrdict(self, H, G):
old_foo = H[1][2]["foo"]
H.adj[1][2]["foo"] = "baz"
assert G.edges == H.edges
H.adj[1][2]["foo"] = old_foo
assert G.edges == H.edges
old_foo = H.nodes[0]["foo"]
H.nodes[0]["foo"] = "baz"
assert G.nodes == H.nodes
H.nodes[0]["foo"] = old_foo
assert G.nodes == H.nodes
def different_attrdict(self, H, G):
old_foo = H[1][2]["foo"]
H.adj[1][2]["foo"] = "baz"
assert G._adj != H._adj
H.adj[1][2]["foo"] = old_foo
assert G._adj == H._adj
old_foo = H.nodes[0]["foo"]
H.nodes[0]["foo"] = "baz"
assert G._node != H._node
H.nodes[0]["foo"] = old_foo
assert G._node == H._node
def graphs_equal(self, H, G):
assert G._adj == H._adj
assert G._node == H._node
assert G.graph == H.graph
assert G.name == H.name
if not G.is_directed() and not H.is_directed():
assert H._adj[1][2] is H._adj[2][1]
assert G._adj[1][2] is G._adj[2][1]
else: # at least one is directed
if not G.is_directed():
G._pred = G._adj
G._succ = G._adj
if not H.is_directed():
H._pred = H._adj
H._succ = H._adj
assert G._pred == H._pred
assert G._succ == H._succ
assert H._succ[1][2] is H._pred[2][1]
assert G._succ[1][2] is G._pred[2][1]
def test_graph_attr(self):
G = self.K3.copy()
G.graph["foo"] = "bar"
assert isinstance(G.graph, G.graph_attr_dict_factory)
assert G.graph["foo"] == "bar"
del G.graph["foo"]
assert G.graph == {}
H = self.Graph(foo="bar")
assert H.graph["foo"] == "bar"
def test_node_attr(self):
G = self.K3.copy()
G.add_node(1, foo="bar")
assert all(
isinstance(d, G.node_attr_dict_factory) for u, d in G.nodes(data=True)
)
assert nodes_equal(G.nodes(), [0, 1, 2])
assert nodes_equal(G.nodes(data=True), [(0, {}), (1, {"foo": "bar"}), (2, {})])
G.nodes[1]["foo"] = "baz"
assert nodes_equal(G.nodes(data=True), [(0, {}), (1, {"foo": "baz"}), (2, {})])
assert nodes_equal(G.nodes(data="foo"), [(0, None), (1, "baz"), (2, None)])
assert nodes_equal(
G.nodes(data="foo", default="bar"), [(0, "bar"), (1, "baz"), (2, "bar")]
)
def test_node_attr2(self):
G = self.K3.copy()
a = {"foo": "bar"}
G.add_node(3, **a)
assert nodes_equal(G.nodes(), [0, 1, 2, 3])
assert nodes_equal(
G.nodes(data=True), [(0, {}), (1, {}), (2, {}), (3, {"foo": "bar"})]
)
def test_edge_lookup(self):
G = self.Graph()
G.add_edge(1, 2, foo="bar")
assert edges_equal(G.edges[1, 2], {"foo": "bar"})
def test_edge_attr(self):
G = self.Graph()
G.add_edge(1, 2, foo="bar")
assert all(
isinstance(d, G.edge_attr_dict_factory) for u, v, d in G.edges(data=True)
)
assert edges_equal(G.edges(data=True), [(1, 2, {"foo": "bar"})])
assert edges_equal(G.edges(data="foo"), [(1, 2, "bar")])
def test_edge_attr2(self):
G = self.Graph()
G.add_edges_from([(1, 2), (3, 4)], foo="foo")
assert edges_equal(
G.edges(data=True), [(1, 2, {"foo": "foo"}), (3, 4, {"foo": "foo"})]
)
assert edges_equal(G.edges(data="foo"), [(1, 2, "foo"), (3, 4, "foo")])
def test_edge_attr3(self):
G = self.Graph()
G.add_edges_from([(1, 2, {"weight": 32}), (3, 4, {"weight": 64})], foo="foo")
assert edges_equal(
G.edges(data=True),
[
(1, 2, {"foo": "foo", "weight": 32}),
(3, 4, {"foo": "foo", "weight": 64}),
],
)
G.remove_edges_from([(1, 2), (3, 4)])
G.add_edge(1, 2, data=7, spam="bar", bar="foo")
assert edges_equal(
G.edges(data=True), [(1, 2, {"data": 7, "spam": "bar", "bar": "foo"})]
)
def test_edge_attr4(self):
G = self.Graph()
G.add_edge(1, 2, data=7, spam="bar", bar="foo")
assert edges_equal(
G.edges(data=True), [(1, 2, {"data": 7, "spam": "bar", "bar": "foo"})]
)
G[1][2]["data"] = 10 # OK to set data like this
assert edges_equal(
G.edges(data=True), [(1, 2, {"data": 10, "spam": "bar", "bar": "foo"})]
)
G.adj[1][2]["data"] = 20
assert edges_equal(
G.edges(data=True), [(1, 2, {"data": 20, "spam": "bar", "bar": "foo"})]
)
G.edges[1, 2]["data"] = 21 # another spelling, "edge"
assert edges_equal(
G.edges(data=True), [(1, 2, {"data": 21, "spam": "bar", "bar": "foo"})]
)
G.adj[1][2]["listdata"] = [20, 200]
G.adj[1][2]["weight"] = 20
dd = {
"data": 21,
"spam": "bar",
"bar": "foo",
"listdata": [20, 200],
"weight": 20,
}
assert edges_equal(G.edges(data=True), [(1, 2, dd)])
def test_to_undirected(self):
G = self.K3
self.add_attributes(G)
H = nx.Graph(G)
self.is_shallow_copy(H, G)
self.different_attrdict(H, G)
H = G.to_undirected()
self.is_deepcopy(H, G)
def test_to_directed_as_view(self):
H = nx.path_graph(2, create_using=self.Graph)
H2 = H.to_directed(as_view=True)
assert H is H2._graph
assert H2.has_edge(0, 1)
assert H2.has_edge(1, 0) or H.is_directed()
pytest.raises(nx.NetworkXError, H2.add_node, -1)
pytest.raises(nx.NetworkXError, H2.add_edge, 1, 2)
H.add_edge(1, 2)
assert H2.has_edge(1, 2)
assert H2.has_edge(2, 1) or H.is_directed()
def test_to_undirected_as_view(self):
H = nx.path_graph(2, create_using=self.Graph)
H2 = H.to_undirected(as_view=True)
assert H is H2._graph
assert H2.has_edge(0, 1)
assert H2.has_edge(1, 0)
pytest.raises(nx.NetworkXError, H2.add_node, -1)
pytest.raises(nx.NetworkXError, H2.add_edge, 1, 2)
H.add_edge(1, 2)
assert H2.has_edge(1, 2)
assert H2.has_edge(2, 1)
def test_directed_class(self):
G = self.Graph()
class newGraph(G.to_undirected_class()):
def to_directed_class(self):
return newDiGraph
def to_undirected_class(self):
return newGraph
class newDiGraph(G.to_directed_class()):
def to_directed_class(self):
return newDiGraph
def to_undirected_class(self):
return newGraph
G = newDiGraph() if G.is_directed() else newGraph()
H = G.to_directed()
assert isinstance(H, newDiGraph)
H = G.to_undirected()
assert isinstance(H, newGraph)
def test_to_directed(self):
G = self.K3
self.add_attributes(G)
H = nx.DiGraph(G)
self.is_shallow_copy(H, G)
self.different_attrdict(H, G)
H = G.to_directed()
self.is_deepcopy(H, G)
def test_subgraph(self):
G = self.K3
self.add_attributes(G)
H = G.subgraph([0, 1, 2, 5])
self.graphs_equal(H, G)
self.same_attrdict(H, G)
self.shallow_copy_attrdict(H, G)
H = G.subgraph(0)
assert H.adj == {0: {}}
H = G.subgraph([])
assert H.adj == {}
assert G.adj != {}
def test_selfloops_attr(self):
G = self.K3.copy()
G.add_edge(0, 0)
G.add_edge(1, 1, weight=2)
assert edges_equal(
nx.selfloop_edges(G, data=True), [(0, 0, {}), (1, 1, {"weight": 2})]
)
assert edges_equal(
nx.selfloop_edges(G, data="weight"), [(0, 0, None), (1, 1, 2)]
)
class TestGraph(BaseAttrGraphTester):
"""Tests specific to dict-of-dict-of-dict graph data structure"""
def setup_method(self):
self.Graph = nx.Graph
# build dict-of-dict-of-dict K3
ed1, ed2, ed3 = ({}, {}, {})
self.k3adj = {0: {1: ed1, 2: ed2}, 1: {0: ed1, 2: ed3}, 2: {0: ed2, 1: ed3}}
self.k3edges = [(0, 1), (0, 2), (1, 2)]
self.k3nodes = [0, 1, 2]
self.K3 = self.Graph()
self.K3._adj = self.k3adj
self.K3._node = {}
self.K3._node[0] = {}
self.K3._node[1] = {}
self.K3._node[2] = {}
def test_pickle(self):
G = self.K3
pg = pickle.loads(pickle.dumps(G, -1))
self.graphs_equal(pg, G)
pg = pickle.loads(pickle.dumps(G))
self.graphs_equal(pg, G)
def test_data_input(self):
G = self.Graph({1: [2], 2: [1]}, name="test")
assert G.name == "test"
assert sorted(G.adj.items()) == [(1, {2: {}}), (2, {1: {}})]
def test_adjacency(self):
G = self.K3
assert dict(G.adjacency()) == {
0: {1: {}, 2: {}},
1: {0: {}, 2: {}},
2: {0: {}, 1: {}},
}
def test_getitem(self):
G = self.K3
assert G.adj[0] == {1: {}, 2: {}}
assert G[0] == {1: {}, 2: {}}
with pytest.raises(KeyError):
G.__getitem__("j")
with pytest.raises(TypeError):
G.__getitem__(["A"])
def test_add_node(self):
G = self.Graph()
G.add_node(0)
assert G.adj == {0: {}}
# test add attributes
G.add_node(1, c="red")
G.add_node(2, c="blue")
G.add_node(3, c="red")
assert G.nodes[1]["c"] == "red"
assert G.nodes[2]["c"] == "blue"
assert G.nodes[3]["c"] == "red"
# test updating attributes
G.add_node(1, c="blue")
G.add_node(2, c="red")
G.add_node(3, c="blue")
assert G.nodes[1]["c"] == "blue"
assert G.nodes[2]["c"] == "red"
assert G.nodes[3]["c"] == "blue"
def test_add_nodes_from(self):
G = self.Graph()
G.add_nodes_from([0, 1, 2])
assert G.adj == {0: {}, 1: {}, 2: {}}
# test add attributes
G.add_nodes_from([0, 1, 2], c="red")
assert G.nodes[0]["c"] == "red"
assert G.nodes[2]["c"] == "red"
# test that attribute dicts are not the same
assert G.nodes[0] is not G.nodes[1]
# test updating attributes
G.add_nodes_from([0, 1, 2], c="blue")
assert G.nodes[0]["c"] == "blue"
assert G.nodes[2]["c"] == "blue"
assert G.nodes[0] is not G.nodes[1]
# test tuple input
H = self.Graph()
H.add_nodes_from(G.nodes(data=True))
assert H.nodes[0]["c"] == "blue"
assert H.nodes[2]["c"] == "blue"
assert H.nodes[0] is not H.nodes[1]
# specific overrides general
H.add_nodes_from([0, (1, {"c": "green"}), (3, {"c": "cyan"})], c="red")
assert H.nodes[0]["c"] == "red"
assert H.nodes[1]["c"] == "green"
assert H.nodes[2]["c"] == "blue"
assert H.nodes[3]["c"] == "cyan"
def test_remove_node(self):
G = self.K3.copy()
G.remove_node(0)
assert G.adj == {1: {2: {}}, 2: {1: {}}}
with pytest.raises(nx.NetworkXError):
G.remove_node(-1)
# generator here to implement list,set,string...
def test_remove_nodes_from(self):
G = self.K3.copy()
G.remove_nodes_from([0, 1])
assert G.adj == {2: {}}
G.remove_nodes_from([-1]) # silent fail
def test_add_edge(self):
G = self.Graph()
G.add_edge(0, 1)
assert G.adj == {0: {1: {}}, 1: {0: {}}}
G = self.Graph()
G.add_edge(*(0, 1))
assert G.adj == {0: {1: {}}, 1: {0: {}}}
G = self.Graph()
with pytest.raises(ValueError):
G.add_edge(None, "anything")
def test_add_edges_from(self):
G = self.Graph()
G.add_edges_from([(0, 1), (0, 2, {"weight": 3})])
assert G.adj == {
0: {1: {}, 2: {"weight": 3}},
1: {0: {}},
2: {0: {"weight": 3}},
}
G = self.Graph()
G.add_edges_from([(0, 1), (0, 2, {"weight": 3}), (1, 2, {"data": 4})], data=2)
assert G.adj == {
0: {1: {"data": 2}, 2: {"weight": 3, "data": 2}},
1: {0: {"data": 2}, 2: {"data": 4}},
2: {0: {"weight": 3, "data": 2}, 1: {"data": 4}},
}
with pytest.raises(nx.NetworkXError):
G.add_edges_from([(0,)]) # too few in tuple
with pytest.raises(nx.NetworkXError):
G.add_edges_from([(0, 1, 2, 3)]) # too many in tuple
with pytest.raises(TypeError):
G.add_edges_from([0]) # not a tuple
with pytest.raises(ValueError):
G.add_edges_from([(None, 3), (3, 2)]) # None cannot be a node
def test_remove_edge(self):
G = self.K3.copy()
G.remove_edge(0, 1)
assert G.adj == {0: {2: {}}, 1: {2: {}}, 2: {0: {}, 1: {}}}
with pytest.raises(nx.NetworkXError):
G.remove_edge(-1, 0)
def test_remove_edges_from(self):
G = self.K3.copy()
G.remove_edges_from([(0, 1)])
assert G.adj == {0: {2: {}}, 1: {2: {}}, 2: {0: {}, 1: {}}}
G.remove_edges_from([(0, 0)]) # silent fail
def test_clear(self):
G = self.K3.copy()
G.graph["name"] = "K3"
G.clear()
assert list(G.nodes) == []
assert G.adj == {}
assert G.graph == {}
def test_clear_edges(self):
G = self.K3.copy()
G.graph["name"] = "K3"
nodes = list(G.nodes)
G.clear_edges()
assert list(G.nodes) == nodes
assert G.adj == {0: {}, 1: {}, 2: {}}
assert list(G.edges) == []
assert G.graph["name"] == "K3"
def test_edges_data(self):
G = self.K3
all_edges = [(0, 1, {}), (0, 2, {}), (1, 2, {})]
assert edges_equal(G.edges(data=True), all_edges)
assert edges_equal(G.edges(0, data=True), [(0, 1, {}), (0, 2, {})])
assert edges_equal(G.edges([0, 1], data=True), all_edges)
with pytest.raises(nx.NetworkXError):
G.edges(-1, True)
def test_get_edge_data(self):
G = self.K3.copy()
assert G.get_edge_data(0, 1) == {}
assert G[0][1] == {}
assert G.get_edge_data(10, 20) is None
assert G.get_edge_data(-1, 0) is None
assert G.get_edge_data(-1, 0, default=1) == 1
def test_update(self):
# specify both edgees and nodes
G = self.K3.copy()
G.update(nodes=[3, (4, {"size": 2})], edges=[(4, 5), (6, 7, {"weight": 2})])
nlist = [
(0, {}),
(1, {}),
(2, {}),
(3, {}),
(4, {"size": 2}),
(5, {}),
(6, {}),
(7, {}),
]
assert sorted(G.nodes.data()) == nlist
if G.is_directed():
elist = [
(0, 1, {}),
(0, 2, {}),
(1, 0, {}),
(1, 2, {}),
(2, 0, {}),
(2, 1, {}),
(4, 5, {}),
(6, 7, {"weight": 2}),
]
else:
elist = [
(0, 1, {}),
(0, 2, {}),
(1, 2, {}),
(4, 5, {}),
(6, 7, {"weight": 2}),
]
assert sorted(G.edges.data()) == elist
assert G.graph == {}
# no keywords -- order is edges, nodes
G = self.K3.copy()
G.update([(4, 5), (6, 7, {"weight": 2})], [3, (4, {"size": 2})])
assert sorted(G.nodes.data()) == nlist
assert sorted(G.edges.data()) == elist
assert G.graph == {}
# update using only a graph
G = self.Graph()
G.graph["foo"] = "bar"
G.add_node(2, data=4)
G.add_edge(0, 1, weight=0.5)
GG = G.copy()
H = self.Graph()
GG.update(H)
assert graphs_equal(G, GG)
H.update(G)
assert graphs_equal(H, G)
# update nodes only
H = self.Graph()
H.update(nodes=[3, 4])
assert H.nodes ^ {3, 4} == set()
assert H.size() == 0
# update edges only
H = self.Graph()
H.update(edges=[(3, 4)])
assert sorted(H.edges.data()) == [(3, 4, {})]
assert H.size() == 1
# No inputs -> exception
with pytest.raises(nx.NetworkXError):
nx.Graph().update()
class TestEdgeSubgraph:
"""Unit tests for the :meth:`Graph.edge_subgraph` method."""
def setup_method(self):
# Create a path graph on five nodes.
G = nx.path_graph(5)
# Add some node, edge, and graph attributes.
for i in range(5):
G.nodes[i]["name"] = f"node{i}"
G.edges[0, 1]["name"] = "edge01"
G.edges[3, 4]["name"] = "edge34"
G.graph["name"] = "graph"
# Get the subgraph induced by the first and last edges.
self.G = G
self.H = G.edge_subgraph([(0, 1), (3, 4)])
def test_correct_nodes(self):
"""Tests that the subgraph has the correct nodes."""
assert [0, 1, 3, 4] == sorted(self.H.nodes())
def test_correct_edges(self):
"""Tests that the subgraph has the correct edges."""
assert [(0, 1, "edge01"), (3, 4, "edge34")] == sorted(self.H.edges(data="name"))
def test_add_node(self):
"""Tests that adding a node to the original graph does not
affect the nodes of the subgraph.
"""
self.G.add_node(5)
assert [0, 1, 3, 4] == sorted(self.H.nodes())
def test_remove_node(self):
"""Tests that removing a node in the original graph does
affect the nodes of the subgraph.
"""
self.G.remove_node(0)
assert [1, 3, 4] == sorted(self.H.nodes())
def test_node_attr_dict(self):
"""Tests that the node attribute dictionary of the two graphs is
the same object.
"""
for v in self.H:
assert self.G.nodes[v] == self.H.nodes[v]
# Making a change to G should make a change in H and vice versa.
self.G.nodes[0]["name"] = "foo"
assert self.G.nodes[0] == self.H.nodes[0]
self.H.nodes[1]["name"] = "bar"
assert self.G.nodes[1] == self.H.nodes[1]
def test_edge_attr_dict(self):
"""Tests that the edge attribute dictionary of the two graphs is
the same object.
"""
for u, v in self.H.edges():
assert self.G.edges[u, v] == self.H.edges[u, v]
# Making a change to G should make a change in H and vice versa.
self.G.edges[0, 1]["name"] = "foo"
assert self.G.edges[0, 1]["name"] == self.H.edges[0, 1]["name"]
self.H.edges[3, 4]["name"] = "bar"
assert self.G.edges[3, 4]["name"] == self.H.edges[3, 4]["name"]
def test_graph_attr_dict(self):
"""Tests that the graph attribute dictionary of the two graphs
is the same object.
"""
assert self.G.graph is self.H.graph