chore: import upstream snapshot with attribution

easygraph/readwrite/tests/test_graphviz.py

@@ -0,0 +1,58 @@
+import os
+import tempfile
+
+import pytest
+
+
+pygraphviz = pytest.importorskip("pygraphviz")
+
+import easygraph as eg
+
+from easygraph.utils import edges_equal
+from easygraph.utils import nodes_equal
+
+
+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 = eg.to_agraph(G)
+        H = eg.from_agraph(A)
+        self.assert_equal(G, H)
+
+        fd, fname = tempfile.mkstemp()
+        eg.write_dot(H, fname)
+        Hin = eg.read_dot(fname)
+        self.assert_equal(H, Hin)
+        os.close(fd)
+        os.unlink(fname)
+
+        (fd, fname) = tempfile.mkstemp()
+        with open(fname, "w") as fh:
+            eg.write_dot(H, fh)
+
+        with open(fname) as fh:
+            Hin = eg.read_dot(fh)
+        os.close(fd)
+        os.unlink(fname)
+        self.assert_equal(H, Hin)
+
+    def test_from_agraph_name(self):
+        G = eg.Graph(name="test")
+        A = eg.to_agraph(G)
+        H = eg.from_agraph(A)
+        assert G.name == "test"
+
+    def test_undirected(self):
+        self.agraph_checks(eg.Graph())