const graph = new Graph();
 
const vertexA = new GraphVertex('A');
const vertexB = new GraphVertex('B');
const vertexC = new GraphVertex('C');
const vertexD = new GraphVertex('D');
 
const edgeAB = new GraphEdge(vertexA, vertexB, 1);
const edgeBC = new GraphEdge(vertexB, vertexC, 2);
const edgeCD = new GraphEdge(vertexC, vertexD, 3);
const edgeAD = new GraphEdge(vertexA, vertexD, 4);
 
graph
    .addEdge(edgeAB)
    .addEdge(edgeBC)
    .addEdge(edgeCD)
    .addEdge(edgeAD);
 
expect(graph.getWeight()).toBe(10);