Function TestNonSequentialReads

tensorflow/core/lib/io/recordio_test.cc:251–283

}

void TestNonSequentialReads(const RecordWriterOptions& writer_options,
                            const RecordReaderOptions& reader_options) {
  string contents;
  StringDest dst(&contents);
  RecordWriter writer(&dst, writer_options);
  for (int i = 0; i < 10; ++i) {
    TF_ASSERT_OK(writer.WriteRecord(NumberString(i))) << i;
  }
  TF_ASSERT_OK(writer.Close());

  StringSource file(&contents);
  RecordReader reader(&file, reader_options);

  string record;
  // First read sequentially to fill in the offsets table.
  uint64 offsets[10] = {0};
  uint64 offset = 0;
  for (int i = 0; i < 10; ++i) {
    offsets[i] = offset;
    TF_ASSERT_OK(reader.ReadRecord(&offset, &record)) << i;
  }

  // Read randomly: First go back to record #3 then forward to #8.
  offset = offsets[3];
  TF_ASSERT_OK(reader.ReadRecord(&offset, &record));
  EXPECT_EQ("3.", record);
  EXPECT_EQ(offsets[4], offset);

  offset = offsets[8];
  TF_ASSERT_OK(reader.ReadRecord(&offset, &record));
  EXPECT_EQ("8.", record);
  EXPECT_EQ(offsets[9], offset);
}

TEST_F(RecordioTest, NonSequentialReads) {
  TestNonSequentialReads(RecordWriterOptions(), RecordReaderOptions());