@Test
public void testAvoidOverflowWithZero() {

  LongDiffNullArrayEdges edges = getEdges();
  List<Edge<LongWritable, NullWritable>> initialEdges = Lists.newArrayList(
      createEdge(5223372036854775807L), createEdge(-4223372036854775807L), createEdge(0));
  edges.initialize(initialEdges);
  assertEdges(edges, -4223372036854775807L, 0, 5223372036854775807L);
}