Evaluate and improve test suites across C++, Python, Rust, and Java.
npx skills add https://github.com/tswr/engineering-mastery-plugin --skill testing-tswr
Please help me install this Agent Skill. Skill: testing Source: https://github.com/tswr/engineering-mastery-plugin/tree/main/skills/testing Command: npx skills add https://github.com/tswr/engineering-mastery-plugin --skill testing-tswr
This Skill solves the pervasive problem of low-value test suites that create an illusion of safety while slowing development, breaking on every internal refactor, and failing to catch real regressions. Many teams waste hours maintaining tests that provide zero protection, or skip writing tests entirely because they don't know how to write ones that last.
Use the testing skill to write a set of unit tests for the new user authentication feature that verify behavior through the public API and only mock external payment and email services.
High-intent search queries and answers about installing and using this skill.
Unit tests break during refactoring because they assert implementation details instead of observable behavior. Testing through the public API and avoiding mocks for internal dependencies ensures refactoring resistance and prevents false test failures.
Write characterization tests for legacy code by capturing and locking in its current observable behavior. This approach creates a safety net that detects regressions before you add targeted unit tests for new features.
Use mocks and test doubles only for external unmanaged dependencies like payment or email services. Restricting mocks prevents brittle tests and ensures your test suite maintains high regression protection and maintainability.
Yes, this testing approach supports TDD workflows across C++, Python, Rust, and Java by providing language-specific reference patterns for test structure, dependency injection, and property-based testing.
The four pillars of valuable tests are regression protection, refactoring resistance, fast feedback, and maintainability. Evaluating tests against these criteria eliminates low-value suites that slow development velocity.
Review existing tests by enforcing behavior-focused testing and checking adherence to the four pillars of valuable tests. This eliminates brittle tests that fail to catch real regressions and slow development.
TrebuchetDynamicsProve a single Gormes behavior with red-green-refactor tests.
kevinnftEnforce a test-first workflow with failing tests before minimal code.
LerianStudioDetect testing anti-patterns in codebases during test reviews and CI validation.
copyleftdevInject faults into source code and calculate mutation scores for test suites.
