"""Unit tests for PyGraphviz interface.""" import os import tempfile import pytest pygraphviz = pytest.importorskip("pygraphviz") from networkx.testing import assert_edges_equal, assert_nodes_equal, assert_graphs_equal import networkx as nx class TestAGraph: def build_graph(self, G): edges = [("A", "B"), ("A", "C"), ("A", "C"), ("B", "C"), ("A", "D")] G.add_edges_from(edges) G.add_node("E") G.graph["metal"] = "bronze" return G def assert_equal(self, G1, G2): assert_nodes_equal(G1.nodes(), G2.nodes()) assert_edges_equal(G1.edges(), G2.edges()) assert G1.graph["metal"] == G2.graph["metal"] def agraph_checks(self, G): G = self.build_graph(G) A = nx.nx_agraph.to_agraph(G) H = nx.nx_agraph.from_agraph(A) self.assert_equal(G, H) fname = tempfile.mktemp() nx.drawing.nx_agraph.write_dot(H, fname) Hin = nx.nx_agraph.read_dot(fname) os.unlink(fname) self.assert_equal(H, Hin) (fd, fname) = tempfile.mkstemp() with open(fname, "w") as fh: nx.drawing.nx_agraph.write_dot(H, fh) with open(fname) as fh: Hin = nx.nx_agraph.read_dot(fh) os.unlink(fname) self.assert_equal(H, Hin) def test_from_agraph_name(self): G = nx.Graph(name="test") A = nx.nx_agraph.to_agraph(G) H = nx.nx_agraph.from_agraph(A) assert G.name == "test" @pytest.mark.parametrize( "graph_class", (nx.Graph, nx.DiGraph, nx.MultiGraph, nx.MultiDiGraph) ) def test_from_agraph_create_using(self, graph_class): G = nx.path_graph(3) A = nx.nx_agraph.to_agraph(G) H = nx.nx_agraph.from_agraph(A, create_using=graph_class) assert isinstance(H, graph_class) def test_from_agraph_named_edges(self): # Create an AGraph from an existing (non-multi) Graph G = nx.Graph() G.add_nodes_from([0, 1]) A = nx.nx_agraph.to_agraph(G) # Add edge (+ name, given by key) to the AGraph A.add_edge(0, 1, key="foo") # Verify a.name roundtrips out to 'key' in from_agraph H = nx.nx_agraph.from_agraph(A) assert isinstance(H, nx.Graph) assert ("0", "1", {"key": "foo"}) in H.edges(data=True) def test_undirected(self): self.agraph_checks(nx.Graph()) def test_directed(self): self.agraph_checks(nx.DiGraph()) def test_multi_undirected(self): self.agraph_checks(nx.MultiGraph()) def test_multi_directed(self): self.agraph_checks(nx.MultiDiGraph()) def test_to_agraph_with_nodedata(self): G = nx.Graph() G.add_node(1, color="red") A = nx.nx_agraph.to_agraph(G) assert dict(A.nodes()[0].attr) == {"color": "red"} @pytest.mark.parametrize("graph_class", (nx.Graph, nx.MultiGraph)) def test_to_agraph_with_edgedata(self, graph_class): G = graph_class() G.add_nodes_from([0, 1]) G.add_edge(0, 1, color="yellow") A = nx.nx_agraph.to_agraph(G) assert dict(A.edges()[0].attr) == {"color": "yellow"} def test_view_pygraphviz_path(self, tmp_path): G = nx.complete_graph(3) input_path = str(tmp_path / "graph.png") out_path, A = nx.nx_agraph.view_pygraphviz(G, path=input_path, show=False) assert out_path == input_path # Ensure file is not empty with open(input_path, "rb") as fh: data = fh.read() assert len(data) > 0 def test_view_pygraphviz_file_suffix(self, tmp_path): G = nx.complete_graph(3) path, A = nx.nx_agraph.view_pygraphviz(G, suffix=1, show=False) assert path[-6:] == "_1.png" def test_view_pygraphviz(self): G = nx.Graph() # "An empty graph cannot be drawn." pytest.raises(nx.NetworkXException, nx.nx_agraph.view_pygraphviz, G) G = nx.barbell_graph(4, 6) nx.nx_agraph.view_pygraphviz(G, show=False) def test_view_pygraphviz_edgelabel(self): G = nx.Graph() G.add_edge(1, 2, weight=7) G.add_edge(2, 3, weight=8) path, A = nx.nx_agraph.view_pygraphviz(G, edgelabel="weight", show=False) for edge in A.edges(): assert edge.attr["weight"] in ("7", "8") def test_view_pygraphviz_callable_edgelabel(self): G = nx.complete_graph(3) def foo_label(data): return "foo" path, A = nx.nx_agraph.view_pygraphviz(G, edgelabel=foo_label, show=False) for edge in A.edges(): assert edge.attr["label"] == "foo" def test_view_pygraphviz_multigraph_edgelabels(self): G = nx.MultiGraph() G.add_edge(0, 1, key=0, name="left_fork") G.add_edge(0, 1, key=1, name="right_fork") path, A = nx.nx_agraph.view_pygraphviz(G, edgelabel="name", show=False) edges = A.edges() assert len(edges) == 2 for edge in edges: assert edge.attr["label"].strip() in ("left_fork", "right_fork") def test_graph_with_reserved_keywords(self): # test attribute/keyword clash case for #1582 # node: n # edges: u,v G = nx.Graph() G = self.build_graph(G) G.nodes["E"]["n"] = "keyword" G.edges[("A", "B")]["u"] = "keyword" G.edges[("A", "B")]["v"] = "keyword" A = nx.nx_agraph.to_agraph(G) def test_view_pygraphviz_no_added_attrs_to_input(self): G = nx.complete_graph(2) path, A = nx.nx_agraph.view_pygraphviz(G, show=False) assert G.graph == {} @pytest.mark.xfail(reason="known bug in clean_attrs") def test_view_pygraphviz_leaves_input_graph_unmodified(self): G = nx.complete_graph(2) # Add entries to graph dict that to_agraph handles specially G.graph["node"] = {"width": "0.80"} G.graph["edge"] = {"fontsize": "14"} path, A = nx.nx_agraph.view_pygraphviz(G, show=False) assert G.graph == {"node": {"width": "0.80"}, "edge": {"fontsize": "14"}} def test_graph_with_AGraph_attrs(self): G = nx.complete_graph(2) # Add entries to graph dict that to_agraph handles specially G.graph["node"] = {"width": "0.80"} G.graph["edge"] = {"fontsize": "14"} path, A = nx.nx_agraph.view_pygraphviz(G, show=False) # Ensure user-specified values are not lost assert dict(A.node_attr)["width"] == "0.80" assert dict(A.edge_attr)["fontsize"] == "14" def test_round_trip_empty_graph(self): G = nx.Graph() A = nx.nx_agraph.to_agraph(G) H = nx.nx_agraph.from_agraph(A) # assert_graphs_equal(G, H) AA = nx.nx_agraph.to_agraph(H) HH = nx.nx_agraph.from_agraph(AA) assert_graphs_equal(H, HH) G.graph["graph"] = {} G.graph["node"] = {} G.graph["edge"] = {} assert_graphs_equal(G, HH) @pytest.mark.xfail(reason="integer->string node conversion in round trip") def test_round_trip_integer_nodes(self): G = nx.complete_graph(3) A = nx.nx_agraph.to_agraph(G) H = nx.nx_agraph.from_agraph(A) assert_graphs_equal(G, H) def test_graphviz_alias(self): G = self.build_graph(nx.Graph()) pos_graphviz = nx.nx_agraph.graphviz_layout(G) pos_pygraphviz = nx.nx_agraph.pygraphviz_layout(G) assert pos_graphviz == pos_pygraphviz @pytest.mark.parametrize("root", range(5)) def test_pygraphviz_layout_root(self, root): # NOTE: test depends on layout prog being deterministic G = nx.complete_graph(5) A = nx.nx_agraph.to_agraph(G) # Get layout with root arg is not None pygv_layout = nx.nx_agraph.pygraphviz_layout(G, prog="circo", root=root) # Equivalent layout directly on AGraph A.layout(args=f"-Groot={root}", prog="circo") # Parse AGraph layout a1_pos = tuple(float(v) for v in dict(A.get_node("1").attr)["pos"].split(",")) assert pygv_layout[1] == a1_pos def test_2d_layout(self): G = nx.Graph() G = self.build_graph(G) G.graph["dimen"] = 2 pos = nx.nx_agraph.pygraphviz_layout(G, prog="neato") pos = list(pos.values()) assert len(pos) == 5 assert len(pos[0]) == 2 def test_3d_layout(self): G = nx.Graph() G = self.build_graph(G) G.graph["dimen"] = 3 pos = nx.nx_agraph.pygraphviz_layout(G, prog="neato") pos = list(pos.values()) assert len(pos) == 5 assert len(pos[0]) == 3 def test_display_pygraphviz_deprecation_warning(self): G = nx.complete_graph(2) path_name, A = nx.nx_agraph.view_pygraphviz(G, show=False) # Monkeypatch default_opener to prevent window opening nx.utils.default_opener = lambda x: None with pytest.warns(DeprecationWarning, match="display_pygraphviz is deprecated"): with open(path_name, "wb") as fh: nx.nx_agraph.display_pygraphviz(A, fh, prog="dot")