CtrlK
BlogDocsLog inGet started
Tessl Logo

giuseppe-trisciuoglio/developer-kit

Comprehensive developer toolkit providing reusable skills for Java/Spring Boot, TypeScript/NestJS/React/Next.js, Python, PHP, AWS CloudFormation, AI/RAG, DevOps, and more.

90

Quality

90%

Does it follow best practices?

Impact

Pending

No eval scenarios have been run

SecuritybySnyk

Risky

Do not use without reviewing

This version of the tile failed moderation
Moderation pipeline encountered an internal error
Overview
Quality
Evals
Security
Files

examples.mdplugins/developer-kit-java/skills/unit-test-mapper-converter/references/

Mapper & Converter Test Examples

Setup

Maven

<dependency>
  <groupId>org.mapstruct</groupId>
  <artifactId>mapstruct</artifactId>
  <version>1.5.5.Final</version>
</dependency>
<dependency>
  <groupId>org.junit.jupiter</groupId>
  <artifactId>junit-jupiter</artifactId>
  <scope>test</scope>
</dependency>
<dependency>
  <groupId>org.assertj</groupId>
  <artifactId>assertj-core</artifactId>
  <scope>test</scope>
</dependency>

Gradle

dependencies {
  implementation("org.mapstruct:mapstruct:1.5.5.Final")
  testImplementation("org.junit.jupiter:junit-jupiter")
  testImplementation("org.assertj:assertj-core")
}

Basic Pattern: MapStruct Mapper

@Mapper(componentModel = "spring")
public interface UserMapper {
  UserDto toDto(User user);
  User toEntity(UserDto dto);
  List<UserDto> toDtos(List<User> users);
}

class UserMapperTest {
  private final UserMapper userMapper = Mappers.getMapper(UserMapper.class);

  @Test
  void shouldMapUserToDto() {
    User user = new User(1L, "Alice", "alice@example.com", 25);
    UserDto dto = userMapper.toDto(user);
    assertThat(dto)
      .isNotNull()
      .extracting("id", "name", "email", "age")
      .containsExactly(1L, "Alice", "alice@example.com", 25);
  }

  @Test
  void shouldMapDtoToEntity() {
    UserDto dto = new UserDto(1L, "Alice", "alice@example.com", 25);
    User user = userMapper.toEntity(dto);
    assertThat(user)
      .isNotNull()
      .hasFieldOrPropertyWithValue("id", 1L)
      .hasFieldOrPropertyWithValue("name", "Alice");
  }

  @Test
  void shouldMapListOfUsers() {
    List<User> users = List.of(
      new User(1L, "Alice", "alice@example.com", 25),
      new User(2L, "Bob", "bob@example.com", 30)
    );
    List<UserDto> dtos = userMapper.toDtos(users);
    assertThat(dtos)
      .hasSize(2)
      .extracting(UserDto::getName)
      .containsExactly("Alice", "Bob");
  }

  @Test
  void shouldHandleNullEntity() {
    assertThat(userMapper.toDto(null)).isNull();
  }
}

Nested Object Mapping

class User {
  private Long id;
  private String name;
  private Address address;
  private List<Phone> phones;
}

class NestedObjectMapperTest {
  private final UserMapper userMapper = Mappers.getMapper(UserMapper.class);

  @Test
  void shouldMapNestedAddress() {
    Address address = new Address("123 Main St", "New York", "NY", "10001");
    User user = new User(1L, "Alice", address);
    UserDto dto = userMapper.toDto(user);
    assertThat(dto.getAddress())
      .isNotNull()
      .hasFieldOrPropertyWithValue("street", "123 Main St");
  }

  @Test
  void shouldMapListOfNestedPhones() {
    List<Phone> phones = List.of(
      new Phone("123-456-7890", "MOBILE"),
      new Phone("987-654-3210", "HOME")
    );
    User user = new User(1L, "Alice", null, phones);
    UserDto dto = userMapper.toDto(user);
    assertThat(dto.getPhones())
      .hasSize(2)
      .extracting(PhoneDto::getNumber)
      .containsExactly("123-456-7890", "987-654-3210");
  }

  @Test
  void shouldHandleNullNestedObjects() {
    User user = new User(1L, "Alice", null);
    assertThat(userMapper.toDto(user).getAddress()).isNull();
  }
}

Custom Mapping Methods

@Mapper(componentModel = "spring")
public interface ProductMapper {
  @Mapping(source = "name", target = "productName")
  @Mapping(source = "price", target = "salePrice")
  @Mapping(target = "discount", expression = "java(product.getPrice() * 0.1)")
  ProductDto toDto(Product product);
}

class CustomMappingTest {
  private final ProductMapper mapper = Mappers.getMapper(ProductMapper.class);

  @Test
  void shouldMapFieldsWithCustomNames() {
    Product product = new Product(1L, "Laptop", 999.99);
    ProductDto dto = mapper.toDto(product);
    assertThat(dto)
      .hasFieldOrPropertyWithValue("productName", "Laptop")
      .hasFieldOrPropertyWithValue("salePrice", 999.99);
  }

  @Test
  void shouldCalculateDiscountFromExpression() {
    Product product = new Product(1L, "Laptop", 100.0);
    ProductDto dto = mapper.toDto(product);
    assertThat(dto.getDiscount()).isEqualTo(10.0);
  }
}

Enum Mapping

enum UserStatus { ACTIVE, INACTIVE, SUSPENDED }
enum UserStatusDto { ENABLED, DISABLED, LOCKED }

@Mapper(componentModel = "spring")
public interface StatusMapper {
  @ValueMapping(source = "ACTIVE", target = "ENABLED")
  @ValueMapping(source = "INACTIVE", target = "DISABLED")
  @ValueMapping(source = "SUSPENDED", target = "LOCKED")
  UserStatusDto toStatusDto(UserStatus status);
}

class EnumMapperTest {
  private final StatusMapper mapper = Mappers.getMapper(StatusMapper.class);

  @Test
  void shouldMapActiveToEnabled() {
    assertThat(mapper.toStatusDto(UserStatus.ACTIVE)).isEqualTo(UserStatusDto.ENABLED);
  }

  @Test
  void shouldMapAllEnumValues() {
    for (UserStatus status : UserStatus.values()) {
      assertThat(mapper.toStatusDto(status)).isNotNull();
    }
  }
}

Custom Type Converter

public class DateFormatter {
  private static final DateTimeFormatter formatter = DateTimeFormatter.ofPattern("yyyy-MM-dd");

  public static String format(LocalDate date) {
    return date != null ? date.format(formatter) : null;
  }

  public static LocalDate parse(String dateString) {
    return dateString != null ? LocalDate.parse(dateString, formatter) : null;
  }
}

class DateFormatterTest {
  @Test
  void shouldFormatLocalDateToString() {
    assertThat(DateFormatter.format(LocalDate.of(2024, 1, 15))).isEqualTo("2024-01-15");
  }

  @Test
  void shouldParseStringToLocalDate() {
    assertThat(DateFormatter.parse("2024-01-15")).isEqualTo(LocalDate.of(2024, 1, 15));
  }

  @Test
  void shouldHandleNullInFormat() {
    assertThat(DateFormatter.format(null)).isNull();
  }

  @Test
  void shouldThrowOnInvalidDateFormat() {
    assertThatThrownBy(() -> DateFormatter.parse("invalid-date"))
      .isInstanceOf(DateTimeParseException.class);
  }
}

Bidirectional Mapping (Round Trip)

class BidirectionalMapperTest {
  private final UserMapper mapper = Mappers.getMapper(UserMapper.class);

  @Test
  void shouldMaintainDataInRoundTrip() {
    User original = new User(1L, "Alice", "alice@example.com", 25);
    UserDto dto = mapper.toDto(original);
    User restored = mapper.toEntity(dto);
    assertThat(restored)
      .hasFieldOrPropertyWithValue("id", original.getId())
      .hasFieldOrPropertyWithValue("name", original.getName());
  }

  @Test
  void shouldPreserveAllFieldsInBothDirections() {
    Address address = new Address("123 Main", "NYC", "NY", "10001");
    User user = new User(1L, "Alice", "alice@example.com", 25, address);
    UserDto dto = mapper.toDto(user);
    User restored = mapper.toEntity(dto);
    assertThat(restored).usingRecursiveComparison().isEqualTo(user);
  }
}

Partial Mapping (Update)

@Mapper(componentModel = "spring")
public interface UserMapper {
  void updateEntity(@MappingTarget User entity, UserDto dto);
}

class PartialMapperTest {
  private final UserMapper mapper = Mappers.getMapper(UserMapper.class);

  @Test
  void shouldUpdateExistingEntity() {
    User existing = new User(1L, "Alice", "alice@old.com", 25);
    UserDto dto = new UserDto(1L, "Alice", "alice@new.com", 26);
    mapper.updateEntity(existing, dto);
    assertThat(existing)
      .hasFieldOrPropertyWithValue("email", "alice@new.com")
      .hasFieldOrPropertyWithValue("age", 26);
  }

  @Test
  void shouldNotUpdateFieldsNotInDto() {
    User existing = new User(1L, "Alice", "alice@example.com", 25);
    UserDto dto = new UserDto(1L, "Bob", null, 0);
    mapper.updateEntity(existing, dto);
    assertThat(existing.getEmail()).isEqualTo("alice@example.com");
  }
}

plugins

developer-kit-java

skills

unit-test-mapper-converter

references

examples.md

SKILL.md

README.md

CHANGELOG.md

context7.json

CONTRIBUTING.md

README_CN.md

README_ES.md

README_IT.md

README.md

tessl.json

tile.json