@Test
  public void testIncrementWithReturnResultsSetToFalse() throws Exception {
    byte[] row1 = Bytes.toBytes("row1");
    byte[] col1 = Bytes.toBytes("col1");

    // Setting up region
    WALFactory wals =
      new WALFactory(CONF, ServerName.valueOf("testIncrementWithReturnResultsSetToFalse", 16010,
        EnvironmentEdgeManager.currentTime()).toString());
    HRegion region = createHRegion(wals, Durability.USE_DEFAULT);

    Increment inc1 = new Increment(row1);
    inc1.setReturnResults(false);
    inc1.addColumn(FAMILY, col1, 1);
    Result res = region.increment(inc1);
    assertTrue(res.isEmpty());
  }
Test when returnResults set to false in increment it should not return the result instead it
resturn null.
hbase-server/src/test/java/org/apache/hadoop/hbase/regionserver/wal/TestDurability.java