testing▌

Jest test patterns and best practices for NestJS unit, integration, and e2e testing. \n \n Covers the testing pyramid: unit tests for pure logic, integration tests with real providers using Test.createTestingModule , and e2e tests with supertest for HTTP APIs \n Provides patterns for mocking external services with jest.fn and test doubles, plus in-memory database adapters and test containers for data layer testing \n Emphasizes deterministic tests with proper mock reset between runs, avoiding sh

SQL and Rust testing guide covering test types, execution, and writing patterns. \n \n Three primary test formats: .sqltest (preferred for SQL compatibility across backends), TCL .test (legacy, being phased out), and Rust integration tests for regression and complex scenarios \n Run tests via make test for the full suite, make -C testing/sqltests run-cli for SQL tests, or cargo test for Rust tests \n .sqltest format uses simple declarative syntax with @database , test blocks, and expect sections

Isolated unit testing patterns for Spring service layer using Mockito and JUnit 5. \n \n Covers mocking injected dependencies, verifying service interactions, and testing business logic without database or external API calls \n Includes patterns for exception handling, complex workflows, argument capturing, and verification of call order and frequency \n Supports testing async/reactive services with CompletableFuture and provides best practices for constructor injection and spy-based partial moc

You are an expert in App Store product page optimization and A/B testing. Your goal is to help the user design, run, and interpret tests that improve their App Store conversion rate.

Interactive browser automation with snapshot-based element references and multi-session support. \n \n 40+ commands across navigation, interaction, keyboard/mouse control, storage management, network mocking, and DevTools integration \n Automatic page snapshots after each command with element references (e.g., e15 ) for reliable, context-aware interactions \n Multi-browser support (Chrome, Firefox, WebKit, Edge) with persistent profiles, session management, and named browser instances \n Built-i

Downloads artifacts from a GitHub Actions integration test run, generates a summarized skill invocation report, and files GitHub issues for each test failure with root-cause analysis.

Comprehensive Java testing with JUnit 5, Mockito, and integration testing frameworks. \n \n Covers unit testing with JUnit 5 (parameterized tests, lifecycle annotations, extensions), mocking with Mockito (stubbing, verification, BDD style), and fluent assertions with AssertJ \n Includes integration testing patterns using Spring Boot Test slices, Testcontainers for database isolation, and MockMvc for API testing \n Provides test data builders, TDD/BDD practices, and JaCoCo coverage configuration

Iterative test-debug-fix cycles for Airflow DAGs with comprehensive failure diagnosis. \n \n Start with af runs trigger-wait <dag_id> to run a DAG and wait for completion; no pre-flight checks needed \n On failure, use af runs diagnose for comprehensive failure summary and af tasks logs to inspect error details from specific tasks \n Supports custom configuration, timeouts, and retry attempts; handles success, failure, and timeout scenarios with clear response interpretation \n Quick valida

Cross-browser E2E testing with Page Objects, authentication, and CI/CD integration. \n \n Supports three browser engines (Chromium, Firefox, WebKit) plus mobile viewports with parallel test execution and automatic retries \n Page Object Model pattern with base classes, role-based locators, and web-first assertions that auto-wait and retry \n Built-in authentication setup, API mocking, visual testing, and comprehensive dead link detection across entire sites \n GitHub Actions integration with art

Jest testing patterns, factory functions, and TDD workflows for unit test development. \n \n Covers TDD red-green-refactor cycle, behavior-driven testing focused on public APIs, and factory pattern for reusable test data and component props \n Provides custom render utilities, mock strategies for modules and GraphQL hooks, and structured test organization with describe blocks \n Includes query patterns (getBy, queryBy, findBy), user interaction simulation with fireEvent, and anti-patterns to avo