| name | code-coverage |
| description | Measure and improve Provenant's Rust test coverage locally with cargo-llvm-cov. Use for code coverage, llvm-cov, finding untested code, test gaps, or "what isn't tested". |
Code Coverage (local signal)
Coverage in Provenant is a local tool for finding untested code, not a CI gate
or a number to maximize. See docs/TESTING_STRATEGY.md
for the "confidence, not coverage" philosophy. Use this to locate genuinely
untested paths, then write meaningful behavior tests for them — do not add tests
just to move the number.
Prerequisites
cargo-llvm-cov is installed by npm run setup. Otherwise:
cargo install --locked cargo-llvm-cov
Commands
npm run coverage
npm run coverage:html
cargo llvm-cov --lib -- copyright::refiner
cargo llvm-cov --lib --show-missing-lines -- <filter>
How to read it
--lib covers unit tests only. Integration suites (tests/*.rs) and
golden suites (--features golden-tests) exercise far more code than this
credits, so treat the number as a lower bound. A file showing 0% may still
be well-covered by golden/integration tests.- Low coverage on pure data tables (e.g.
copyright/grammar/rules.rs) or generated
code is expected and not worth "fixing".
- Prioritize gaps in branching logic: error paths, parser fallbacks, edge cases
in detection/assembly — places where a wrong branch produces wrong output.
Workflow to close a real gap
- Run
npm run coverage and pick a module with thin coverage on real logic.
- Re-run scoped (
cargo llvm-cov --lib --show-missing-lines -- <module>) to see the
exact uncovered lines.
- Confirm the lines aren't already covered by a golden/integration suite before
assuming they're untested (grep the relevant
tests/ and *_scan_test.rs).
- Add behavior-focused tests per
docs/TESTING_STRATEGY.md
(right layer: unit vs scan/assembly contract vs golden).
- Re-run scoped coverage to confirm the gap is closed.
