name: testing-strategy description: 'Designs unit, integration and end-to-end testing strategies and implements tests for code changes.' metadata: id: ce.skill.testing-strategy tags: [testing, validation, performance] inputs: files: [ARCHITECTURE.md, CONTRIBUTING.md] concepts: [test-pyramid] tools: [toolset:write] outputs: artifacts: [ce.task.validate] files: [] actions: [apply-changes] dependsOn: artifacts: [ce.task.validate] files: [.vscode/tasks.json] related: artifacts: [ce.prompt.write-tests] files: []

Testing Strategy Skill

This skill ensures that new features are accompanied by robust tests across the testing pyramid.

Steps

1. Review context. Load ARCHITECTURE.md and CONTRIBUTING.md to understand the system architecture, critical paths and existing testing conventions.

2. Plan test coverage. Determine which layers of the testing pyramid apply:

   • Unit tests for individual functions or classes.
   • Integration tests for interactions between modules or services.
   • End‑to‑end tests for verifying user-facing workflows.

3. Identify key scenarios. For each requirement or plan step, outline the positive, negative and edge case scenarios that must be tested. Consider performance and security aspects where applicable.

4. Select frameworks and tools. Choose appropriate testing frameworks (e.g. pytest for Python, Jest for JS/TS) and any mocking or fixture libraries. Ensure tests can run in isolation and in CI.

5. Write and organise tests. Implement the tests following language-specific best practices. Place them in clearly named files and directories. Use descriptive test names and assertions.

6. Run and iterate. Execute the tests locally. Fix any failing tests or code issues. Ensure the entire suite passes quickly. Address flakiness or excessive coupling.

7. Validate and summarise. Run the validation task to ensure no structural issues were introduced. Summarise the new tests and their coverage. Highlight any remaining gaps for future work.

Embedding testing as a first-class activity guarantees reliability and facilitates confident refactoring.