Prompt file imported from mwill20/Governed_AI_Pipeline (.claude/commands/test-gen.md). Fill in {{arguments}} before use. Copyright stays with the author.

/test-gen — Test Generation for Changed Files

Generate or extend tests for the code changed in the current diff, then run them.

Identify what changed

Changed files: !git diff --name-only HEAD

Target override (if provided): {{arguments}}

Procedure

1. For each changed Python source file (skip files already under tests/), locate or create the matching test module (tests/test_<name>.py, following the project's existing layout).
2. Write tests that cover, in priority order:
   • Security-relevant behavior — input validation, boundary/trust checks, error paths.
   • The happy path.
   • Edge cases — empty input, wrong type, oversized input.
3. Follow the existing test style in tests/ (fixtures, naming, assertions). Read a nearby test first; do not invent a new convention.
4. Run the suite for the changed files, with coverage if pytest-cov is available: python3 -m pytest tests/ -q --cov=<changed_package> --cov-report=term-missing (fall back to plain python3 -m pytest tests/ -q if pytest-cov is not installed).
5. If tests fail, fix the test if the test is wrong, or report the source bug — do not weaken an assertion just to make it pass.

Output

• List of test files created/updated.
• Pytest result (pass/fail counts).
• Coverage for the changed files (percentage + which lines are still uncovered), or a note that pytest-cov is not installed and how to add it.
• Any source bug the tests surfaced.

A change is not done until its tests pass. Report honestly if they do not.