cuioss/cui-testing

CUI Testing Skill

REFERENCE MODE: This skill provides reference material. Load specific standards on-demand based on current task.

CUI-specific testing standards for projects using CUI test libraries. This skill covers the mandatory test data generator framework, value object contract testing, and JUL log testing utilities.

Enforcement

Execution mode: Reference library; load standards progressively based on current testing task.

Prohibited actions:

• Do not use manual test data, Random, UUID, or Faker; must use CUI Generators framework
• Do not use Mockito or PowerMock in CUI projects; use EasyMock or CUI test patterns
• Do not load all standards at once; load progressively based on current task

Constraints:

• All test classes must use @EnableGeneratorController annotation
• Value object tests must implement ShouldHandleObjectContracts<T> contract interface
• Log verification tests must use @EnableTestLogger and LogAsserts
• Parameterized tests must use @GeneratorsSource with typed generators

Prerequisites

This skill requires CUI test library dependencies:

• de.cuioss.test:cui-test-generator (Generators, TypedGenerator)
• de.cuioss.test:cui-test-value-objects (ShouldHandleObjectContracts)
• de.cuioss.test:cui-test-juli (EnableTestLogger, LogAsserts)

Workflow

Step 1: Load Test Generator Framework

CRITICAL: Load this standard for any test implementation work.

Read: standards/test-generator-framework.md

This provides the foundational rules:

• MANDATORY use of Generators.* for ALL test data
• FORBIDDEN: Manual test data, Random, Faker
• REQUIRED: @EnableGeneratorController annotation

Step 2: Load Additional Standards (As Needed)

Value Object Testing (load for domain object tests):

Read: standards/testing-value-objects.md

Use when: Testing value objects, implementing equals/hashCode contracts, or using ShouldHandleObjectContracts<T>.

JUL Log Testing (load for log verification tests):

Read: standards/testing-juli-logger.md

Use when: Testing code that uses CUI logging and needs to verify log output with @EnableTestLogger and LogAsserts.

Key Rules Summary

Test Data Generation

// CORRECT - Use Generators
@EnableGeneratorController
class MyServiceTest {
    @Test
    void shouldProcess() {
        String input = Generators.nonEmptyStrings().next();
        // ...
    }
}

// FORBIDDEN - Never use manual data or Random
String input = "test"; // WRONG
String input = UUID.randomUUID().toString(); // WRONG

Parameterized Tests

// CORRECT - Use @GeneratorsSource
@ParameterizedTest
@GeneratorsSource(EmailGenerator.class)
void shouldValidateEmail(String email) {
    // Test with generated emails
}

Value Object Contracts

// Implements automatic contract testing
class PersonTest implements ShouldHandleObjectContracts<Person> {
    @Override
    public Person getUnderTest() {
        return new PersonGenerator().next();
    }
}

Log Testing

@EnableTestLogger
class MyServiceTest {
    @Test
    void shouldLogWarning() {
        // Execute code that logs
        service.processWithWarning();

        // Verify log output
        LogAsserts.assertLogMessagePresentContaining(TestLogLevel.WARN, "expected message");
    }
}

Forbidden Libraries (CUI Projects)

| Library | Reason | Alternative | |---------|--------|-------------| | Mockito | Use CUI framework alternatives | EasyMock for simple mocking, cui-test-mockwebserver-junit5 for HTTP | | PowerMock | Refactor to dependency injection | EasyMock or CUI test patterns |

When encountering Mockito in existing CUI code:

• Replace when().thenReturn() with EasyMock equivalents or dependency injection
• Use cui-test-mockwebserver-junit5 for HTTP client testing
• See pm-dev-java-cui:cui-http-testing for MockWebServer patterns

Related Skills

• plan-marshall:dev-general-module-testing - Language-agnostic testing principles (AAA, coverage, reliability)
• pm-dev-java:junit-core - General JUnit 5 patterns (no CUI dependencies)
• pm-dev-java-cui:cui-logging - CUI logging standards (use with cui-testing for log tests)

Standards Reference

| Standard | Purpose | |----------|---------| | test-generator-framework.md | Mandatory test data generation | | testing-value-objects.md | Contract testing for value objects | | testing-juli-logger.md | JUL log testing with LogAsserts |