My Emacs configuration https://git.cjennings.net/dotemacs/atom?h=load-graph-classify-end 2026-04-23T00:58:00+00:00 2026-04-23T00:58:00+00:00 Craig Jennings c@cjennings.net 2026-04-23T00:58:00+00:00 urn:sha1:a97266c0e89ef8560824789063512d2613849fc9 Completes the coverage v1 pipeline by adding the Makefile target, the undercover driver script, the exclusion list, and the .gitignore entry. Uses simplecov JSON rather than LCOV as the collection format. The LCOV vs simplecov choice: Undercover's :merge-report t option only supports simplecov. Since the pipeline runs tests per-file (matching test-unit's isolation pattern) and accumulates coverage across runs, merge-report is required. LCOV is better-supported by external coverage viewers, but for a primarily interactive workflow the on-disk format is an internal detail. Other moves in this commit: - Renamed cj/--coverage-parse-lcov to cj/--coverage-parse-simplecov and rewrote its tests for the JSON schema. Same signature, same semantics (file to set of covered lines), different parser. - Renamed the backend protocol's :lcov-path key to :report-path, format-neutral and matching the renamed cj/--coverage-elisp-report-path function. - The coverage target deletes modules/*.elc before running so undercover can instrument the .el sources. Without this, byte-compiled versions shadow the instrumentation and only a handful of pre-loaded modules end up with coverage data. - Excluded tests/test-all-comp-errors.el from make coverage runs. That test byte-compiles every module, which fails under undercover's instrumentation. Excluded only from coverage. Normal make test still runs it. - Updated docs/design/coverage.org to reflect the simplecov pivot with a historical note on why we moved off LCOV. Verified end-to-end: make coverage produces .coverage/simplecov.json with 2717 of 4559 executable lines hit across 44 tracked modules. 2026-04-22T22:12:41+00:00 Craig Jennings c@cjennings.net 2026-04-22T22:12:41+00:00 urn:sha1:071b25d43ad21eb1f5e7e74822bbf2cfa8f58b4e The coverage-core module now has a registry protocol so per-language backends can plug in without touching the core. A backend is a plist with :name, :detect, :run, and :lcov-path. cj/coverage-register-backend appends to cj/coverage-backends, or replaces an existing entry with the same :name at its original position (so first-registered wins on ties). cj/--coverage-backend-for-project resolves which backend applies to a project root. Resolution order: 1. An OVERRIDE argument (typically buffer-local cj/coverage-backend from .dir-locals.el) wins if supplied, and errors if it names an unregistered backend. 2. Otherwise, walk the registry in order and return the first backend whose :detect returns non-nil for the given root. Tests cover Normal (register and retrieve, re-register replaces in place, first detect wins), Boundary (empty registry, no match, override bypasses detect, detect receives the root), and Error (override names an unknown backend). With the registry in place, the elisp backend (and later python / typescript / go) can self-register on load without any changes to coverage-core.