Change GraphTopologyConversion::convert return value to include the new GraphIsomorphism

This allows to convert maps for the converted graph.

src/models/graph.rs

@@ -6,8 +6,8 @@ use typed_generational_arena::{Arena, Index};
 use crate::maps::ElementMap;
 use crate::models;
 use crate::traits::{
-    GraphTopology, GraphTopologyAddition, GraphTopologyConversion, GraphTopologyDeletion,
-    Incidence, IncidenceCursor,
+    GraphIsomorphism, GraphTopology, GraphTopologyAddition, GraphTopologyConversion,
+    GraphTopologyDeletion, Incidence, IncidenceCursor,
 };
 
 /// An opaque handle identifying a vertex in a [`Graph`].
@@ -399,19 +399,14 @@ impl GraphTopologyDeletion for Graph {
 }
 
 impl GraphTopologyConversion for Graph {
-    fn convert<H: GraphTopology>(
-        source: &H,
-    ) -> (
-        Self,
-        ElementMap<H::Vertex, Vertex>,
-        ElementMap<H::Edge, Edge>,
-    ) {
+    fn convert<G: GraphTopology>(source: &G) -> (Self, GraphIsomorphism<G, Self>) {
         let mut edge_map = source.edge_map(Edge::new(usize::MAX, usize::MAX));
         let (result, vertex_map) =
             models::convert_to_addition(source, Vertex::new(usize::MAX, usize::MAX), |e, new_e| {
                 edge_map[e] = new_e
             });
-        (result, vertex_map, edge_map)
+        let iso = GraphIsomorphism::new(&result, vertex_map, edge_map);
+        (result, iso)
     }
 }