assertEquals(10, result.getCounters().getCounter(CounterNames.MAPPER_CALLS).getValue());
ArrayList<Long> results = new ArrayList<>();
GcsService gcsService = GcsServiceFactory.createGcsService();
ByteBuffer holder = ByteBuffer.allocate(8);
for (GcsFilename file : result.getOutputResult().getFiles()) {
try (GcsInputChannel channel = gcsService.openPrefetchingReadChannel(file, 0, 4096)) {
int read = channel.read(holder);
while (read != -1) {
holder.rewind();
results.add(holder.getLong());
holder.rewind();