PILOT_COUNT_ZERO is dead in all 14 locales (uppercase _ZERO never matches Intl.PluralRules lowercase categories)

[kgNatx]

Severity: P3 | Subsystem: i18n-sw | Category: i18n

Location: /home/kyleg/containers/atxfpv.org/skwad/static/locales/en.json:PILOT_COUNT_ZERO entry

What

tPlural builds the lookup key as key + '_' + rule where rule = Intl.PluralRules(lang).select(count) (i18n.js:34-37). Intl returns lowercase CLDR categories ('zero','one','two','few','many','other'), never the uppercase 'ZERO'. Every locale defines PILOT_COUNT_ZERO (uppercase) — confirmed present in all 14 files — so that string is unreachable. Additionally, English PluralRules has only ['one','other'] categories (verified via node), so count=0 selects 'other' and renders PILOT_COUNT_other = "0 PILOTS" rather than the special PILOT_COUNT_ZERO = "0 PILOTS". The only caller is app.js:2738 ($('pilot-count').textContent = tPlural('PILOT_COUNT', count)). Net effect: dead key plus a latent trap — if anyone later relies on a true zero category (e.g., a locale that has one), the uppercase key would still never match. Functionally harmless today because en's _other text already reads "0 PILOTS".

Suggested fix

Either delete PILOT_COUNT_ZERO from all locales (simplest — it's never reachable), or rename to lowercase PILOT_COUNT_zero AND only add it for locales whose Intl.PluralRules actually expose a 'zero' category (none of the current 14 do).

Verification

Traced the full path. tPlural (i18n.js:34-37) builds the lookup as key + '' + rule where rule = Intl.PluralRules(currentLang).select(count), which returns lowercase CLDR categories. The fallback chain is strings[lang][key+''+rule] || strings[lang][key+'_other'] — it never references _ZERO. All 14 locale files define the uppercase PILOT_COUNT_ZERO (confirmed 14/14 via grep). I verified via node that none of the 14 supported locales even expose a 'zero' plural category, and that count=0 selects 'other' (en/ja/zh/etc.), 'one' (fr), or 'many' (pl). So PILOT_COUNT_ZERO is unreachable in every locale — confirmed dead key. The only caller is app.js:2738. Impact is purely dead config: count=0 still renders correctly via _other (or _one for fr, which is the correct French convention), so there is no user-facing breakage today. The 'latent trap' framing is mild overstatement since a future zero-category locale would need the lowercase key regardless. P3 is correct — no functional impact, just dead keys and a naming inconsistency.

_{Filed from the 2026-05-30 multi-agent codebase review.}