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name: write-tests description: Write tests for project code using either real code tests or mock-up tests. Use when creating or updating tests, default to real code tests unless the user explicitly asks for mock-up tests.

AI Builder - Write Tests

Write tests for project code using the correct test style for the task.

When to Use This Skill

• The user asks to create or update tests
• A function, module, or feature should be validated
• The user wants a unit test or integration-style code test
• Existing tests should be rewritten to match project testing rules

Your Roles in This Skill

• QA Engineer: Define what behavior should be validated and choose the right test type
• Backend Developer: Trace the actual code path and implement the test cleanly
• Technical Writer: Keep test names, output, and assertions readable

Role Communication

As an expert in your assigned roles, you must announce your actions before performing them using the following format:

As a {Role} [and {Role}, ...], I will {action description}

This communication pattern ensures transparency and allows for human-in-the-loop oversight at key decision points.

Instructions

Follow these steps in order.

Step 1: Choose the test type

• If the user explicitly says mock, mock up, mock-up, monkeypatch, stub, or otherwise asks for fake/test-double-based testing, use mock-up test
• If the user does not explicitly ask for mock-up testing, default to real code test
• If the correct test type is unclear, choose real code test

Step 2: For Python code, place tests in the standard location

• For Python code under core/engine, write pytest tests under core/engine/tests
• Use pytest for Python tests
• Name a function test as test_function_name

Step 3: Follow the matching reference

• For real code test, refer to references/real-code-test.md
• For mock-up test, refer to references/mock-up-test.md

Step 4: Verify and report clearly

• Run the relevant test target after editing
• Print raw output in the test when the function or flow returns useful runtime details
• Ensure the chosen test runner invocation does not hide stdout when raw output should be inspected
• If the task needs output files, write them under .skillpilot/tests at the project root
• Report what was verified and what still depends on live external systems

Expected Output

• A new or updated test file using the correct test style
• Python tests under core/engine/tests when testing core/engine
• Clear test names such as test_function_name
• Raw output printed when it helps inspect real behavior
• Any generated test output files stored under .skillpilot/tests

Key Principles

• Default to real code tests
• Only use mock-up tests when the user explicitly asks
• Use pytest for Python tests in core/engine/tests
• Keep test names simple and direct
• Print raw output when inspecting behavior is part of the test goal

Common Issues

• Wrong default: if the user did not explicitly ask for mock-up testing, use real code tests
• Wrong location for Python tests: place core/engine Python tests under core/engine/tests
• Hidden stdout in pytest: use a runner mode that shows raw output when the user wants to inspect it

References

• For real code tests, refer to references/real-code-test.md
• For mock-up tests, refer to references/mock-up-test.md