fix: revert the commit that prevented the addition of vertices with integer names, refs #693

Author: ntamas

CHANGELOG.md

@@ -8,6 +8,8 @@
 
 - `Graph.get_incidence()` is now deprecated in favour of `Graph.get_biadjacency()` as it returns the _bipartite adjacency_ matrix of a graph and not its incidence matrix. (The previous name was a mistake). Future versions might re-introduce `Graph.get_incidence()` to return the incidence matrix of a graph.
 
+- Reverted the change in 0.10.5 that prevented adding vertices with integers as vertex names. Now we show a deprecation warning instead, and the addition of vertices with integer names will be prevented from version 0.11.0 only.
+
 ### Fixed
 
 - Fixed a minor memory leak in `Graph.decompose()`.

src/igraph/basic.py

@@ -1,5 +1,6 @@
 from igraph._igraph import GraphBase
 from igraph.seq import EdgeSeq
+from igraph.utils import deprecated
 
 
 def _add_edge(graph, source, target, **kwds):
@@ -58,7 +59,14 @@ def _add_vertex(graph, name=None, **kwds):
         to avoid the overhead of creating t.
     """
     if isinstance(name, int):
-        raise TypeError("cannot use integers as vertex names; use strings instead")
+        # raise TypeError("cannot use integers as vertex names; use strings instead")
+        deprecated(
+            "You are using integers as vertex names. This is discouraged because "
+            "most igraph functions interpret integers as vertex _IDs_ and strings "
+            "as vertex names. For sake of consistency, convert your vertex "
+            "names to strings before assigning them. Future versions from igraph "
+            "0.11.0 will disallow integers as vertex names."
+        )
 
     vid = graph.vcount()
     graph.add_vertices(1)

tests/test_basic.py

@@ -120,8 +120,6 @@ def testAddVertex(self):
         self.assertTrue("name" in g.vertex_attributes())
         self.assertEqual(g.vs["name"], [None, "foo"])
 
-        self.assertRaises(TypeError, g.add_vertex, 3)
-
         vertex = g.add_vertex("3")
         self.assertTrue(g.vcount() == 3 and g.ecount() == 0)
         self.assertEqual(2, vertex.index)
@@ -141,6 +139,9 @@ def testAddVertex(self):
         self.assertEqual(g.vs["spam"], [None] * 4 + ["cheese"])
         self.assertEqual(g.vs["ham"], [None] * 4 + [42])
 
+        with self.assertWarns(DeprecationWarning, msg="integers as vertex names"):
+            g.add_vertex(42)
+
     def testAddVertices(self):
         g = Graph()
         g.add_vertices(2)