testing▌

Unit and integration testing for Angular v20+ with Vitest or Jasmine, supporting signals and modern patterns. \n \n Supports both Vitest (recommended) and Jasmine test runners with native Angular v20+ integration via @angular/build \n Covers signal-based components, computed values, OnPush change detection, and input/output testing with modern APIs \n Includes HTTP mocking via HttpTestingController , service injection with TestBed.inject() , and dependency mocking with Vitest \n Provides pattern

Risk-based quality engineering strategy for modern software delivery.

Write failing tests first, then minimal code to pass, then refactor while keeping tests green. \n \n Follows the red-green-refactor cycle: write one failing test, verify it fails correctly, implement minimal code to pass, verify all tests pass, then refactor safely \n Requires watching each test fail before writing implementation code; tests that pass immediately prove nothing about correctness \n Applies to all new features, bug fixes, refactoring, and behavior changes; code written before test

Cross-browser end-to-end testing with auto-wait, parallel execution, and built-in debugging tools. \n \n Supports Chromium, Firefox, and WebKit across desktop and mobile devices with automatic element waiting and network control \n Includes role-based locators, page object model patterns, and storage-state authentication for maintainable test suites \n Offers visual regression testing via screenshot comparison, video recording, and trace viewer for debugging failed tests \n Built-in test runner

Playwright E2E testing patterns with Page Object Model, configuration, CI/CD setup, and flaky test strategies. \n \n Provides Page Object Model structure for maintainable test organization, with reusable page classes that encapsulate locators and navigation logic \n Covers multi-browser testing across Chromium, Firefox, WebKit, and mobile devices with configurable retries, parallelization, and artifact capture (screenshots, videos, traces) \n Includes flaky test identification and remediation pa

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

Browser automation and testing toolkit for local web applications using Playwright. \n \n Supports core browser interactions including navigation, form filling, clicking, dropdown selection, and dialog handling \n Includes verification capabilities for element presence, text content, visibility, URLs, and responsive design across viewports \n Provides debugging tools: screenshot capture, console log inspection, network request monitoring, and error handling patterns \n Works with Node.js environ

E2E testing utilities for Clerk authentication flows in Playwright and Cypress. \n \n Supports both Playwright and Cypress frameworks with framework-specific setup patterns (globalSetup for Playwright, custom commands for Cypress) \n Provides clerkSetup() and setupClerkTestingToken() utilities to initialize test environments and bypass bot detection \n Includes storageState persistence to reuse authenticated sessions across tests, reducing test execution time \n Requires test API keys ( pk_test_

Mutation testing assesses test suite quality by introducing small changes (mutations) to source code and verifying that tests fail. If tests don't catch a mutation, it indicates gaps in test coverage or test quality. This technique helps identify weak or ineffective tests.

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