How does it handle complex nested objects?

The skill demonstrates how to use AssertJ's recursive comparison to verify entire object trees and nested collections accurately in a single assertion.

Does this skill support MapStruct specifically?

Yes, it provides specific patterns for testing MapStruct interfaces, including non-Spring standalone setups using Mappers.getMapper().

Does it cover null handling in mappers?

Yes, verifying that null inputs produce the expected outputs (such as nulls or default values) is a core instruction provided by this skill.

Can I use this for custom Java converters?

Absolutely. The skill includes patterns for testing manual converter classes, static transformation methods, and non-MapStruct mapping logic.

Java Mapper Unit Testing

Name: Java Mapper Unit Testing
Author: giuseppe-trisciuoglio

bygiuseppe-trisciuoglio

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126

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Security & Testing

Simplifies the creation of robust unit tests for Java object mappers and MapStruct converters to ensure accurate data transformation.

This skill provides specialized patterns and best practices for unit testing MapStruct mappers and custom Java converter classes. It enables developers to validate complex object transformations between DTOs and domain entities in isolation, covering critical scenarios such as nested object hierarchies, null-safe mapping, bidirectional symmetry, and custom enum translations. By leveraging industry-standard tools like AssertJ and JUnit 5, it helps ensure data integrity across architectural layers before moving to more expensive integration tests.

Key Features

01126 GitHub stars

02Nested object and collection mapping tests

03Comprehensive MapStruct testing patterns

04Null-safety and edge case verification

05Custom @Mapping and expression validation

06Bidirectional transformation validation

Use Cases

01Verifying complex DTO-to-Entity conversions in Spring Boot applications

02Ensuring MapStruct @Mapping annotations correctly handle custom logic

03Testing recursive object transformations to maintain data integrity across deep hierarchies

What are Skills?·How to Install

Install with 🐟 Skill.Fish

npx skillfish add giuseppe-trisciuoglio/developer-kit unit-test-mapper-converter

For use in Claude.ai and ChatGPT

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