Function ReflectionTest

3rd_party/flatbuffers/tests/test.cpp:665–843

}

void ReflectionTest(uint8_t *flatbuf, size_t length) {
  // Load a binary schema.
  std::string bfbsfile;
  TEST_EQ(flatbuffers::LoadFile((test_data_path + "monster_test.bfbs").c_str(),
                                true, &bfbsfile),
          true);

  // Verify it, just in case:
  flatbuffers::Verifier verifier(
      reinterpret_cast<const uint8_t *>(bfbsfile.c_str()), bfbsfile.length());
  TEST_EQ(reflection::VerifySchemaBuffer(verifier), true);

  // Make sure the schema is what we expect it to be.
  auto &schema = *reflection::GetSchema(bfbsfile.c_str());
  auto root_table = schema.root_table();
  TEST_EQ_STR(root_table->name()->c_str(), "MyGame.Example.Monster");
  auto fields = root_table->fields();
  auto hp_field_ptr = fields->LookupByKey("hp");
  TEST_NOTNULL(hp_field_ptr);
  auto &hp_field = *hp_field_ptr;
  TEST_EQ_STR(hp_field.name()->c_str(), "hp");
  TEST_EQ(hp_field.id(), 2);
  TEST_EQ(hp_field.type()->base_type(), reflection::Short);
  auto friendly_field_ptr = fields->LookupByKey("friendly");
  TEST_NOTNULL(friendly_field_ptr);
  TEST_NOTNULL(friendly_field_ptr->attributes());
  TEST_NOTNULL(friendly_field_ptr->attributes()->LookupByKey("priority"));

  // Make sure the table index is what we expect it to be.
  auto pos_field_ptr = fields->LookupByKey("pos");
  TEST_NOTNULL(pos_field_ptr);
  TEST_EQ(pos_field_ptr->type()->base_type(), reflection::Obj);
  auto pos_table_ptr = schema.objects()->Get(pos_field_ptr->type()->index());
  TEST_NOTNULL(pos_table_ptr);
  TEST_EQ_STR(pos_table_ptr->name()->c_str(), "MyGame.Example.Vec3");

  // Now use it to dynamically access a buffer.
  auto &root = *flatbuffers::GetAnyRoot(flatbuf);

  // Verify the buffer first using reflection based verification
  TEST_EQ(flatbuffers::Verify(schema, *schema.root_table(), flatbuf, length),
          true);

  auto hp = flatbuffers::GetFieldI<uint16_t>(root, hp_field);
  TEST_EQ(hp, 80);

  // Rather than needing to know the type, we can also get the value of
  // any field as an int64_t/double/string, regardless of what it actually is.
  auto hp_int64 = flatbuffers::GetAnyFieldI(root, hp_field);
  TEST_EQ(hp_int64, 80);
  auto hp_double = flatbuffers::GetAnyFieldF(root, hp_field);
  TEST_EQ(hp_double, 80.0);
  auto hp_string = flatbuffers::GetAnyFieldS(root, hp_field, &schema);
  TEST_EQ_STR(hp_string.c_str(), "80");

  // Get struct field through reflection
  auto pos_struct = flatbuffers::GetFieldStruct(root, *pos_field_ptr);
  TEST_NOTNULL(pos_struct);