Beagle SCM

JS-090 LOW: modularity cleanup batch — dead checkout.apply, 3 short-hex resolvers, duplicated helpers

A batch of low-severity modularity nits surfaced across the JS tree: dead code whose header still advertises an unused API, three overlapping short-hex resolvers, and helpers (ancestor walk, sub-traversal, stdout writers, require idioms) re-implemented per module instead of shared. One TODO per item; each is independently landable. Method: Issues.

Input

Context

• checkout.js:125-162 apply() + its scanWt(:129) are dead —

  the header (:7) advertises apply() but no caller drives it.

• THREE short-hex resolvers: resolve.js:40 (tips-only resolveHex),

  store.js:302 (resolveHexAny, any-object), log.js:104-134 (a pack-walk re-impl, see JS-085).

• patchscope.js:82-119 ancestorSet/lca re-implement the dag

  walk locally ("so patchscope has no dag cycle", :81).

• status.js:247-304 + diff.js:229-248 re-implement sub-recurse

  (joinPrefix/isMount) that core/recurse.js already exports (walk :74, isMount :32, joinPrefix :63).

• delete.js:47-49 re-defines join/statExists/statKind.
• THREE stdout writers: bro.js:33-44 (writeStdout/writeStderr),

  render.js:35 (writeStdout), pager.js:26 (ttyWrite) — all io.buf+feed+io.writeAll(fd,…).

• subs.js:53 lazy require(.../core/discover.js) — a shared→core

  upward require (also in JS-088).

• refs.js:26-36 writes fd1 via io.log(...) directly instead of

  the ctx.out header sink (refs.js:4 admits ctx.out is a no-op stub).

Goals

• Delete checkout.apply()+scanWt; trim the header (:7) claim.
• Make resolve.resolveHex a thin tips-first wrapper over

  store.resolveHexAny; drop the log.js variant (JS-085).

• Fold patchscope ancestorSet/lca onto dag.js.
• Consolidate status/diff sub-recurse onto core/recurse.js::walk.
• delete.js uses shared/util/path.js join + a shared statExists.
• One fd-parameterised writer shared by bro/render/pager.
• refs.js emits via ctx.out, not io.log.

Constraints

• Byte-identical output for every touched verb (get/log/diff/

  status/patch/refs); existing parity tests stay green.

• No new bindings; libabc/libdog only.

WIP

Design decisions

• Land as independent commits, one per TODO — each reversible.
• resolveHex stays the SEED-only tips fast-path (resolve.js:39

  comment) but delegates the prefix scan to resolveHexAny.

TODOs

• Repro-first: a parity test per touched verb pinning current bytes.
• Delete checkout.apply()+scanWt: MOOT — apply is now LIVE (shared/submount.js:273,320),

  no longer dead; fix its missing-object bug instead (see JS-083).

• resolveHex -> wrapper over resolveHexAny; drop log.js variant.
• Fold patchscope ancestorSet/lca onto dag.js.
• Status/diff sub-recurse -> core/recurse.js::walk.
• delete.js -> shared util join/statExists.
• One fd-parameterised stdout writer (bro/render/pager).
• refs.js header -> ctx.out instead of io.log.

Blockers and bummers

• ← JS-085 (log.js resolver) + JS-088 (subs.js require).

• 2026-07-07 audit: STILL OPEN except the apply-delete item (now moot, above). Confirmed live:

  3 short-hex resolvers (resolve.js/store.js:303/log.js:121); patchscope ancestorSet/lca local (patchscope.js:83,101); delete.js local join/statExists/statKind (:55-57); 3 stdout writers (pager.js:81 ttyWrite, view/render.js:54 writeStdout, views/bro/bro.js:34 writeStdout); subs.js:53 lazy core/ require.

Outcome

• (pending)