public Edge convertToEdge(final String outVertexName, String edgeLabel, final String inVertexName) {
        return convertToEdge(graph, outVertexName, edgeLabel, inVertexName);
    }
Looks up the identifier as generated by the current source graph being tested.

@param graph      the graph to get the element id from
@param vertexName a unique string that will identify a graph element within a graph
@return the id as generated by the graph
gremlin-test/src/main/java/org/apache/tinkerpop/gremlin/AbstractGremlinTest.java