Coverage Gate

Codecov blocks PRs that decrease per-file statement coverage. Fork PRs skip the upload and are not gated. Three status checks run on same-repo PRs:

• project — overall coverage must not drop below the base commit.
• patch — changed lines must have coverage at least equal to the project baseline.
• changes — no individual file's coverage may decrease vs the base commit.

If any check fails, Codecov posts a comment listing the affected files with baseline, current, and delta percentages. Fix regressions by adding tests for the uncovered code paths before merging.

Configuration lives in codecov.yml at the repo root. Two CI jobs upload reports — test under flag go and vscode-extension under flag typescript. Each flag scopes the report to its language's files.

Branch and function coverage

Statement coverage does not track which branches of an if or switch were taken. gobco provides condition-level branch coverage:

go tool -modfile=tools/go.mod gobco ./...

Flags:

• -branch — report branch coverage instead of condition coverage.
• -list-all — include fully-covered conditions in the output (default: only partially-covered).
• -stats file.json — persist results across runs to track progress over time.

Reproducing CI statement coverage locally

mkdir -p e2e-cover
E2E_COVERDIR=e2e-cover \
  go test -covermode=atomic \
  -coverprofile=unit.cov ./...
head -1 unit.cov > merged.cov
tail -n +2 unit.cov \
  | grep -v 'cmd/mdsmith/' >> merged.cov || true
tail -n +2 e2e-cover/e2e_coverage.txt \
  | grep 'cmd/mdsmith/' >> merged.cov
go tool cover -func=merged.cov

Unit tests cannot cover cmd/mdsmith/ because those functions run in a subprocess. The merge replaces those zero-count unit lines with the e2e counts. CI performs additional validation (mode header match, file existence); see the test job in .github/workflows/ci.yml.