cpp-testing

Overview of cpp-testing skill

The cpp-testing skill helps you write, run, and debug C++ tests with a practical workflow centered on GoogleTest/GoogleMock, CMake, and CTest. It is best for people who need to add coverage, stabilize flaky tests, or set up a repeatable test harness for modern C++ code, not for general C++ feature work.

What cpp-testing is for

Use the cpp-testing skill when the job is to make tests more reliable or more useful: new unit tests, integration tests, regression coverage, failing-test triage, or sanitizer-backed debugging. The main value is decision support for test design and execution, especially when you need to choose between mocks, fakes, test fixtures, or CTest-driven runs.

Who should use it

This cpp-testing skill fits C++ developers, build-system owners, and agents working in repositories that already use or can adopt GoogleTest/CTest. It is especially useful when a task description is vague but clearly test-related, such as “fix the flaky suite,” “add coverage for this module,” or “make CI catch this bug earlier.”

What makes it different

Compared with a generic prompt, cpp-testing gives you a narrower test-first workflow: when to use it, when not to use it, how to structure tests, and how to run them in a CI-friendly way. That makes the cpp-testing guide more actionable for Test Automation than a broad “write tests” prompt, because it biases toward isolation, discoverability, and minimal, reproducible verification.

How to Use cpp-testing skill

Install cpp-testing

Install the cpp-testing skill with:

npx skills add affaan-m/everything-claude-code --skill cpp-testing

Then point the agent at the repo that contains your C++ project. The skill is most useful when the agent can inspect your actual build files, test layout, and existing conventions before proposing changes.

Read the right files first

Start with SKILL.md, then check README.md, AGENTS.md, metadata.json, and any rules/, references/, resources/, or scripts/ folders if they exist. In this repository, SKILL.md is the only source file, so the first-pass workflow is simple: read the skill, then map its advice onto your project’s own CMakeLists.txt, test directories, and CI configuration.

Give it a usable task prompt

A strong cpp-testing usage prompt names the code under test, the failure mode, the desired test level, and any constraints. For example: “Add GoogleTest coverage for Parser::parseConfig(); keep tests deterministic, avoid filesystem dependence, and use CMake/CTest so the suite runs in CI.” That gives the skill enough context to choose between unit tests, integration tests, mocks, or fixtures.

Follow the test workflow

Use the skill as a red-green-refactor helper: define the behavior, write or adjust the failing test, make the smallest code change to pass, then clean up the test shape. For flaky tests, ask it to identify likely nondeterminism first, then narrow the run to the failing test via CTest before expanding back to the full suite. For diagnostics, include whether you want assertions, logging, sanitizer guidance, or CI gating advice.

cpp-testing skill FAQ

Is cpp-testing only for GoogleTest projects?

No. GoogleTest/GoogleMock is the default fit, but the underlying cpp-testing skill also applies to CMake/CTest-based C++ projects that need structured test execution, even if the surrounding repository uses extra tooling. If your project does not use C++ or does not have a meaningful test boundary, it is probably the wrong skill.

When should I not use cpp-testing?

Do not use it for feature implementation without any testing change, broad refactors that are not test-driven, or non-C++ repositories. The cpp-testing guide is also a poor fit when the task is primarily performance tuning and there is no test failure, regression, or correctness check to anchor the work.

Is this better than a normal prompt?

Usually yes, when the goal is test execution quality rather than code generation alone. The cpp-testing skill adds opinionated guardrails around isolation, test layout, and CTest usage, which reduces guesswork when the agent has to decide how to structure a test or how to reproduce a failure.

Is it beginner-friendly?

Yes, if you can describe the code under test and the behavior you want verified. The skill is most helpful when the user can supply a concrete example, a failing test name, or a small CMake target; it is less helpful when the request is only “make the tests better.”

How to Improve cpp-testing skill

Provide sharper inputs

The best way to improve cpp-testing output is to supply the exact target, expected behavior, and constraints up front. Good inputs mention the class or function, the kind of test needed, and any hard limits such as “no network,” “no sleeps,” “must run under CTest,” or “must keep tests hermetic.”

Ask for the smallest verifiable change

The cpp-testing skill works best when you ask for a narrow first pass: one failing test, one bug fix, one sanitizer run, or one CI-ready command sequence. That produces clearer diffs and reduces the chance of overengineering the test harness.

Watch for common failure modes

The main failure modes are over-mocking, hidden shared state, and tests that pass locally but fail under CTest or CI. If the first result is weak, iterate by adding the real test entry point, the current fixture setup, and any observed failure output so the skill can reason from evidence instead of assumptions.

Iterate after the first run

Use the first result to refine scope: if the test is too brittle, ask for a more isolated fixture; if it is too shallow, ask for edge cases or regression coverage; if it is too slow, ask for a subset-first execution plan. For cpp-testing for Test Automation, this iterative loop is often where the biggest quality gains come from.