std::pair CreateExampleArrowSchemaAndArrayByNanoarrow()

in src/iceberg/arrow_c_data_internal.cc [30:76]

• 34 lines of code
• 2 McCabe index (conditional complexity)

std::pair<ArrowSchema, ArrowArray> CreateExampleArrowSchemaAndArrayByNanoarrow() {
  ArrowSchema out_schema;

  // Initializes the root struct schema
  NANOARROW_THROW_NOT_OK(ArrowSchemaInitFromType(&out_schema, NANOARROW_TYPE_STRUCT));
  NANOARROW_THROW_NOT_OK(ArrowSchemaAllocateChildren(&out_schema, 2));

  // Set up the non-nullable int64 field
  struct ArrowSchema* int64_field = out_schema.children[0];
  ArrowSchemaInit(int64_field);
  NANOARROW_THROW_NOT_OK(ArrowSchemaInitFromType(int64_field, NANOARROW_TYPE_INT64));
  NANOARROW_THROW_NOT_OK(ArrowSchemaSetName(int64_field, "id"));
  int64_field->flags &= ~ARROW_FLAG_NULLABLE;

  // Set up the nullable string field
  struct ArrowSchema* string_field = out_schema.children[1];
  ArrowSchemaInit(string_field);
  NANOARROW_THROW_NOT_OK(ArrowSchemaInitFromType(string_field, NANOARROW_TYPE_STRING));
  NANOARROW_THROW_NOT_OK(ArrowSchemaSetName(string_field, "name"));
  string_field->flags |= ARROW_FLAG_NULLABLE;

  constexpr int64_t kNumValues = 3;
  std::array<int64_t, kNumValues> int64_values = {1, 2, 3};
  std::array<std::string, kNumValues> string_values = {"a", "b", "c"};

  ArrowArray out_array;
  NANOARROW_THROW_NOT_OK(ArrowArrayInitFromSchema(&out_array, &out_schema, nullptr));
  ArrowArray* int64_array = out_array.children[0];
  ArrowArray* string_array = out_array.children[1];

  NANOARROW_THROW_NOT_OK(ArrowArrayStartAppending(int64_array));
  NANOARROW_THROW_NOT_OK(ArrowArrayStartAppending(string_array));

  for (int64_t i = 0; i < kNumValues; i++) {
    NANOARROW_THROW_NOT_OK(ArrowArrayAppendInt(int64_array, int64_values[i]));
    NANOARROW_THROW_NOT_OK(
        ArrowArrayAppendString(string_array, ArrowCharView(string_values[i].c_str())));
  }

  NANOARROW_THROW_NOT_OK(ArrowArrayFinishBuildingDefault(int64_array, nullptr));
  NANOARROW_THROW_NOT_OK(ArrowArrayFinishBuildingDefault(string_array, nullptr));

  out_array.length = kNumValues;
  out_array.null_count = 0;

  return {out_schema, out_array};
}