@Test
public void testIsDirected() {

    GraphStore graphStore = GraphGenerator.generateTinyGraphStore();
    GraphViewStore store = graphStore.viewStore;
    GraphViewImpl view = store.createView();
    DirectedSubgraph graph = store.getDirectedGraph(view);
    graph.fill();
    Assert.assertTrue(graph.isDirected(graph.getEdge("0")));
}