Beagle SCM

JS-074 MED: core/registry.js — build masks load/syntax errors as unresolved verb

registry.build resolves a verb to its handler via two nested require attempts (views/ then verbs/). Both catches are BLIND to the error kind, so a module that EXISTS but throws at load (syntax error, bad require, throwing top-level) is swallowed and recorded null — later surfacing far away as the misleading "no handler for verb" loop refusal. Method: Issues.

Input

Context

• core/registry.js:36: try { mod = req("views/" + verb + "/" + verb + ".js"); }
• core/registry.js:37-39: `catch (e) { try { mod = req("verbs/"...) }

  catch (e2) { tableverb = null; continue; } } — e/e2` discarded.

• A real not-found is the jab loader's "cannot find" string; a SYNTAX

  error or a throwing top-level require throws a DIFFERENT error, yet both land in the same table[verb] = null not-found bucket.

• core/loop.js:102-106: a null handler is retried lazily, then

  throw "loop: no handler for verb '" + row.verb + "' ..." — so a broken-but-present module is reported as MISSING, hiding the syntax error from the author.

Goals

• A view/verb module that throws at load must SURFACE its real error,

  not be reported as an unresolved verb.

• Only a genuine not-found ("cannot find") stays the try-other-tree /

  leave-absent path.

Constraints

• Keep build's signature + return shape (table[verb] = fn | null).
• Keep the two-tree probe order (views/ then verbs/, names disjoint).
• Match on the jab loader's "cannot find" not-found string ONLY.

WIP

Design decisions

• Re-throw any caught error whose message does NOT contain the require

  "cannot find" not-found marker; treat only not-found as fall-through.

• The views/ catch: if e is NOT not-found, re-throw immediately (do

  NOT fall to the verbs/ probe — the module was found, it threw).

• The verbs/ catch: if e2 is NOT not-found, re-throw; else null.
• Verify the EXACT jab loader not-found string (require.cpp) before

  hard-coding it — a wrong substring re-masks everything.

TODOs

• Repro-first: a fixture view module with a top-level throw (or a

  syntax error); assert build PROPAGATES it, not "no handler for verb".

• Confirm the jab "cannot find" not-found string in require.cpp.
• Gate both catches on that string; re-throw otherwise.

Blockers and bummers

• None — local to core/registry.js.

• 2026-07-07 audit: STILL OPEN — core/registry.js:45-48 both catches discard the error

  (catch(e){ try{...}catch(e2){ table[verb]=null; continue; } }); no "cannot find" check.

Outcome

• (pending)