### Question:
EdgeGraph extends ElementGraph { <E extends Edge> GraphTraversal update(E edge, Object fromId, Object toId) { GraphTraversal traversal = find(edge, fromId, toId); return update(traversal, edge, Properties::of); } EdgeGraph(Graph graph, Query query, GraphTraversalSource g); org.apache.tinkerpop.gremlin.structure.Edge delegate(Edge edge); Edge addEdge(E edge, org.apache.tinkerpop.gremlin.structure.Vertex from,
      AnyTraversal anyTraversal); Edge addEdge(E edge, org.apache.tinkerpop.gremlin.structure.Vertex from,
      SubTraversal... subTraversals); Edge removeEdge(E edge); void reset();  }### Answer:
@Test public void testUpdateElement() { Develops develops = createElement(); edgeGraph.update(traversal, develops, Properties::all); verify(traversal, times(1)).property("since", develops.since()); }