improve-c5-2

name	improve-c5-2
description	Improve readiness criterion C5.2 (Unit Test Coverage) in the current project by generating unit tests for untested code. Raises the fulfillment level by one step.
allowed-tools	Bash Read Write Edit

Improve C5.2 — Unit Test Coverage

Current State

Examine the project to understand its current state:

• Identify the test framework from the dependency manifest or framework configuration files.
• Look for existing test directories and test files to understand what is already tested.
• Look for coverage configuration or threshold settings.
• Look for existing coverage reports to understand current coverage level.
• Look at the source directories to identify untested code that needs tests.

Instructions

Step 1 — Determine current level:

• Level 0: No unit test files exist
• Level 1: Test files exist but coverage < 50% (or no coverage measurement)
• Level 2: ≥ 50% coverage configured or evidenced
• Level 3: ≥ 80% coverage configured or evidenced

Step 2 — Read source files before writing tests: Identify the 3–5 most important untested source files (business logic, utilities, services — not configuration or entry points). Read each file fully before writing tests for it.

Step 3 — Implement the improvement:

If current level is 0 → raise to 1:

1. If no test framework is configured, add one appropriate to the language:
   • Node/TS: add jest and @types/jest to devDependencies in package.json, add jest config, add "test": "jest" script
   • Python: ensure pytest is in requirements/pyproject.toml
2. Write unit tests for the 3–5 most important source files identified above. Place them in the appropriate test directory (tests/, __tests__/, or alongside source with .test.ts suffix).
3. Each test file should have at minimum 3–5 test cases covering the main happy path and one edge case per function/method.

If current level is 1 → raise to 2:

1. Add a coverage threshold of 50% to the test config:
   • Jest: add coverageThreshold: { global: { lines: 50 } } to jest.config
   • pytest: add [tool.coverage.report] fail_under = 50 to pyproject.toml
2. Identify the untested or under-tested source files from the file list above (files with no corresponding test file).
3. Write additional unit tests for the top 5 untested files, focusing on functions with clear inputs and outputs.

If current level is 2 → raise to 3:

1. Raise the coverage threshold to 80%:
   • Jest: update coverageThreshold to 80
   • pytest: update fail_under to 80
2. Identify gaps: find source files with corresponding test files but with clearly low coverage (look for files with many functions but few test cases).
3. Expand existing tests with additional cases: boundary conditions, error paths, and edge cases for the most critical functions.

If already at level 3: Report that C5.2 is already at its maximum level (3) and no improvement is needed.

Step 4 — Report: State what test files were created or modified, what coverage threshold was set, the before and after level.