testing▌

Normative: Test failures must be diagnosable without reading the test source.

This skill provides expert guidance on testing modern Android applications, inspired by "Now in Android". It covers Unit Tests, Hilt Integration Tests, and Screenshot Testing.

Use this skill when managing TestFlight testers, groups, and build distribution.

Web application testing and automation using Playwright with managed server lifecycle. \n \n Includes with_server.py helper script to automatically start and manage single or multiple local servers (backend, frontend, etc.) before running automation scripts \n Provides a reconnaissance-then-action pattern: navigate, wait for network idle, take screenshots, inspect DOM, identify selectors, then execute actions \n Supports both static HTML (file:// URLs) and dynamic webapps; includes example scrip

Test @Scheduled and @Async methods directly without waiting for actual execution. \n \n Call async and scheduled methods directly in tests instead of relying on Spring's async executor or scheduling intervals \n Use CompletableFuture.get() with explicit timeouts to wait for async results, and Awaitility.await() for polling-based assertions on state changes \n Mock dependencies that async methods call, then verify interactions after completion using Mockito \n Test exception handling by catching

Unit testing patterns for Spring Security authorization annotations and role-based access control. \n \n Covers @PreAuthorize , @Secured , and @RolesAllowed method-level security with @WithMockUser test fixtures \n Includes role-based access control (RBAC), expression-based authorization, and custom PermissionEvaluator testing \n Provides MockMvc patterns for testing secured REST endpoints and parameterized role testing strategies \n Demonstrates both allow and deny scenarios, owner-based access

Unit testing patterns for MapStruct mappers and custom converters with comprehensive transformation validation. \n \n Covers field mapping accuracy, null handling, type conversions, nested objects, bidirectional mapping, enum mapping, and partial updates \n Includes Maven and Gradle setup with MapStruct, JUnit 5, and AssertJ dependencies \n Provides patterns for testing simple mappings, nested hierarchies, custom @Mapping annotations, enum @ValueMapping , and @MappingTarget partial updates \n De

Comprehensive testing strategies for LangChain4j applications with mocks, containers, and RAG validation. \n \n Provides unit testing patterns with mock models, integration testing via Testcontainers, and end-to-end workflows for RAG systems, AI Services, and tool execution \n Covers testing pyramid approach: 70% unit tests with mocks, 20% integration tests with real services, 10% end-to-end tests \n Includes specialized patterns for streaming responses, memory management, guardrail assertions,

JUnit 5 parameterized testing patterns for running single test methods with multiple input combinations. \n \n Supports multiple data sources: @ValueSource for simple values, @CsvSource for tabular data, @MethodSource for complex objects, @EnumSource for enum testing, and custom ArgumentsProvider implementations \n Includes boundary value testing, edge case coverage, and systematic validation of multiple scenarios with reduced test duplication \n Offers custom display names for readable test out

Test Spring @ConfigurationProperties bindings, validation, and type conversions without full context startup. \n \n Use ApplicationContextRunner to test property binding in isolation, covering simple properties, nested structures, collections, and type conversions \n Verify validation constraints with @Validated annotations, ensuring invalid values fail appropriately and valid configurations pass \n Test default values, profile-specific configurations, and property name mapping (kebab-case to ca