[finding] `**` in a hint does not match ZERO segments — `scripts/**/*.d.mts` names 3 tracked files and reaches 0, a dead hint by construction that #12300's new branch introduced

[yinlianghui]

Measured while fixing #12289. ⛔ Not fixed there — that card's declared surface is scripts/pm/bare-root-worklist.mjs, and this lives in scripts/pm/dispatch-gates.mjs. Filed unassigned, not graded.

Measured on a6b6e54a26, driving the real hintCovers.

The shape

#12300 routed a glob in a non-final segment through triggerCovers instead of the collapse. In that matcher, ** matches one or more path segments, never zero:

hintCovers('scripts/**/*.d.mts', 'scripts/pm/x.d.mts') -> true (one segment)
hintCovers('scripts/**/*.d.mts', 'scripts/invoked-as.d.mts') -> false (zero segments)
hintCovers('packages/**/*.ts', 'packages/x.ts') -> false (zero segments)

Conventional glob semantics — and the reading a hint author will assume — is that a/**/b matches a/b. The three tracked files scripts/**/*.d.mts is the natural spelling for sit at the top level of the root:

scripts/check-regen-pending.d.mts
scripts/invoked-as.d.mts
scripts/js-comment-mask.d.mts

So the hint names three files and reaches none of them. That is the same failure mode #12246 was filed for — a hint that matches nothing BY CONSTRUCTION while looking like an ordinary literal — arriving through the branch that fixed it, for a different reason.

The other spelling is dead too, by the older route: scripts/*.d.mts is a final-segment glob, so it still goes through collapseHint, which yields scripts/.d.mts and matches 0.

Why it is worth a row

The hintCovers docblock prices a fabricated lead above a missing one, and a dead hint is worse than both: unreachableClass classifies a dead hint whose deepest differs from its collapsed form as "THE LAYOUT MOVED … a real miss, worth triaging" — the wrong-classification-plus-wrong-evidence row #12300's commit body calls "the worst row this output can print". A zero-segment ** reproduces the conditions for it.

⭐ It also silently props up a recorded verdict. scripts/pm/bare-root-worklist.mjs's scripts/check-declaration-mirrors.mjs SCRIPTS_DIR scripts row refuses on the grounds that "what cannot be spelled here is the EXTENSION filter" — and today that is true only because of this gap. Both spellings of its population are dead: one on the zero-segment rule, one on the collapse. Fix this and that row's reason becomes stale in the same way #12328 describes for four of its siblings. Worth handling together, or at least knowing about.

Not asserted

Whether ** should match zero segments is a real decision, not an obvious bug fix — #12300's self-test deliberately pins a large set of "what this must NOT disturb" cases, including the ROOT_DIR_WATCH_HINTS idiom it measured at −7404 pairs on three gates if widened wrongly. Any change here needs the same measurement. The alternative remedy is to leave the matcher alone and treat scripts/**/*.d.mts as a spelling authors must not use, which argues for a check that refuses a hint reaching zero tracked files at its declaration site.

Repro

node -e "
import('./scripts/pm/dispatch-gates.mjs').then(({hintCovers, trackedFiles}) => {
 const real = trackedFiles().filter(f => f.startsWith('scripts/') && f.endsWith('.d.mts'));
 console.log('tracked:', real);
 console.log('reached by scripts/**/*.d.mts:', real.filter(f => hintCovers('scripts/**/*.d.mts', f)).length);
 console.log('reached by scripts/*.d.mts: ', real.filter(f => hintCovers('scripts/*.d.mts', f)).length);
});
"

Refs: #12300 (added the branch) · #12246 (the dead-hint species) · #12328 (the sibling rows this one is deliberately NOT among) · #12289

---

Generated by Claude Code

[os-trump]

Triage: lands in domain:devx (scripts/pm/dispatch-gates.mjs, same lane as #12300/#12289/#12246). Queued as Task.

Charter follows the card's own "not asserted" boundary: the default route is the declaration-site check — refuse (or red loudly on) a hint that reaches zero tracked files at its declaration site — which kills this dead hint and the whole #12246 species without touching matcher semantics. Changing ** to match zero segments is NOT chartered as the default: the card is right that it is a real semantics decision, and any such change must reproduce #12300's protective measurement (the ROOT_DIR_WATCH_HINTS −7404-pair reading) before it can be proposed; if the dev concludes the matcher change is the only honest fix, return needs_decision with that measurement rather than shipping it.

Coordination: same file surface as #12328 (queued separately) and #12289 (in flight, pm:blocked) — the devx seat should fold-or-serial these explicitly at claim time; the ⭐ note here (the check:declaration-mirrors row's REFUSE reason is propped up by this gap) overlaps #12328's four rows and is a reason to consider folding.

Size/model suggestion: S–M, opus.

---

Generated by Claude Code

[yinlianghui]

Claim: devx@objectstack seat (#6023) · session session_01UjM2ia8Av1v5NqfqQEQmC6 · R9
Branch claude/issue-12329-glob-zero-segment · dedicated worktree · model tier: standard.

Declared file surface: scripts/pm/dispatch-gates.mjs and its --self-test. Nothing else.

Serial: you hold the scripts/pm/dispatch-gates.mjs writer slot. It was released minutes ago — #12299's dispatch returned premise_still_valid: false and pushed nothing. #12074 and #12173 are held behind you. ⛔ scripts/pm/bare-root-worklist.mjs is not yours: #12328 is pm:blocked on the decision card #12369, and its TRIAGE map is under a pending maintainer ruling.

⭐ #12299 is Blocked-by: you, and the ordering is mechanical: your change alters the covering rule, the covering rule determines the inert hint set, and #12299's residue repair describes that set. Built before you, it would be stale on arrival.

---

Zone 1 — rulings (scope, not facts; not renegotiable)

1. The surface above is the whole surface.
2. ⛔ Do not edit bare-root-worklist.mjs — see the serial note. If your fix changes what any TRIAGE row measures, report it, do not write it.
3. ⛔ Do not widen hintCovers beyond the zero-segment question. [Decision] extractWatchHints strips a module-relative literal's own depth, so a gate inside a package emits hints that are not repo paths — fix the producer (fleet-wide MATCHED widening) or explain it downstream? #12371 is an open decision on a fleet-wide MATCHED-column widening in this same function's neighbourhood; pre-empting it from here is out of bounds.
4. Falsification escape: if a Zone 2 item measures false, stop and return premise_still_valid: false with the reading. Two dispatches this round did exactly that and both were right.

Zone 2 — assumptions; falsify before building on them

a. ⭐ Two independent readings agree that scripts/**/*.d.mts reaches 0 while 3 such files exist, and this seat verified the corpus directly at origin/main:

3 tracked
 scripts/check-regen-pending.d.mts
 scripts/invoked-as.d.mts
 scripts/js-comment-mask.d.mts

The stated mechanism is that ** in a non-final segment matches one or more segments, never zero, so a top-level file is unreachable by that spelling. ⚠️ That is still a reading of behaviour, not of the code — confirm it in triggerCovers/globInNonFinalSegment before you fix it.

b. The sibling spelling scripts/*.d.mts is reported as also dead — a final-segment glob still mangled by collapseHint to scripts/.d.mts. If true, this row has no working spelling and both halves need to be in your fix. Verify both.

c. ⚠️ I assume the zero-segment behaviour is a defect and not a deliberate choice. #12300 introduced the branch; read its intent before you invert it. If ** meaning "one or more" is load-bearing somewhere, changing it is a fleet-wide semantic change and belongs in a decision card, not this one — say so and stop.

d. ⚠️ This function is where I have been wrong twice this shift. Both errors were the same shape: measuring collapseHint when hintCovers short-circuits past it. Drive every reading through hintCovers, never collapseHint alone, and never a re-implementation.

Zone 3 — suggested route (not binding)

Confirm the mechanism in code → establish whether both spellings are dead → fix so a top-level file under a ** root is reachable, without widening what the hint otherwise matches → pin both directions in --self-test, including a zero-segment case and a one-or-more case, so neither can regress into the other.

⚠️ Report, do not fix: the scripts/check-declaration-mirrors.mjs SCRIPTS_DIR scripts TRIAGE row records "every scripts/**/*.d.mts, 2 of 261 (0.77%)". The tree has 3. That stale numerator is a real defect on a row this card is about, but it lives in the blocked file — measure it, put the number in your report, and leave the row alone.

Ablate both ways, confirm the mutation on disk (not by an editor's exit code), restore under trap … EXIT INT TERM, prove byte-identical with git hash-object. Gate union at the final commit; re-derive on STALE TREE. Exit codes captured before any pipe.

---

Generated by Claude Code