C++ Testing (Agent Skill)
Agent-focused testing workflow for modern C++ (C++17/20) using GoogleTest/GoogleMock with CMake/CTest.
When to Use
- Writing new C++ tests or fixing existing tests
- Designing unit/integration test coverage for C++ components
- Adding test coverage, CI gating, or regression protection
- Configuring CMake/CTest workflows for consistent execution
- Investigating test failures or flaky behavior
- Enabling sanitizers for memory/race diagnostics
When NOT to Use
- Implementing new product features without test changes
- Large-scale refactors unrelated to test coverage or failures
- Performance tuning without test regressions to validate
- Non-C++ projects or non-test tasks
Core Concepts
- TDD loop: red → green → refactor (tests first, minimal fix, then cleanups).
- Isolation: prefer dependency injection and fakes over global state.
- Test layout:
tests/unit,tests/integration,tests/testdata. - Mocks vs fakes: mock for interactions, fake for stateful behavior.
- CTest discovery: use
gtest_discover_tests()for stable test discovery. - CI signal: run subset first, then full suite with
--output-on-failure.
