@Test
  public void testMutateRow_WriteRequestCount() throws Exception {
    byte[] row1 = Bytes.toBytes("row1");
    byte[] fam1 = Bytes.toBytes("fam1");
    byte[] qf1 = Bytes.toBytes("qualifier");
    byte[] val1 = Bytes.toBytes("value1");

    RowMutations rm = new RowMutations(row1);
    Put put = new Put(row1);
    put.addColumn(fam1, qf1, val1);
    rm.add(put);

    this.region = initHRegion(tableName, method, CONF, fam1);
    long wrcBeforeMutate = this.region.writeRequestsCount.longValue();
    this.region.mutateRow(rm);
    long wrcAfterMutate = this.region.writeRequestsCount.longValue();
    Assert.assertEquals(wrcBeforeMutate + rm.getMutations().size(), wrcAfterMutate);
  }
HBASE-16429 Make sure no stuck if roll writer when ring buffer is filled with appends
@throws IOException if IO error occurred during test
hbase-server/src/test/java/org/apache/hadoop/hbase/regionserver/TestHRegion.java