CP-14851: i18n extraction tooling (i18next-cli + ast-grep fallback)

[ruijia1in]

Description

Ticket: CP-14851 (part of epic CP-14646; discovery CP-14647)

Establishes the automated string-extraction tooling for the i18n sweep, staying inside the i18next/Crowdin ecosystem (parity-safe). Builds on the runtime foundation from CP-14849 (now on main via #3999).

What this adds (tooling-only — no product strings externalized here; that's the later sweep ticket):

• i18next.config.ts — i18next-cli 1.66.2 config aligned to the runtime (app/i18n/index.ts): single translation namespace, flat natural-English keys, keySeparator/nsSeparator: false. extract scans app/** and maintains the EN catalog; types generates TS definitions. removeUnusedKeys: false so the manually-seeded catalog isn't wiped while there are ~zero t() consumers yet.
• npm scripts — i18n:extract, i18n:types, i18n:instrument, i18n:check (CI staleness gate via extract --ci).
• TS type-safety — generated app/i18n/@types/resources.d.ts + a declare module 'i18next' augmentation, so t() keys are compile-checked (unknown keys are a type error).
• ast-grep fallback rules (sgconfig.yml + scripts/i18n/rules/) — report-only flags for the patterns i18next-cli instrument structurally misses: string-valued JSX props (title/label/placeholder/message/description), showSnackbar/showAlert args, and accessibilityLabel/accessibilityHint.
• Runtime fix — returnEmptyString: false in app/i18n/index.ts so not-yet-translated keys (seeded as "" for Crowdin) fall back to English instead of rendering blank.

Dependencies introduced: i18next-cli + @ast-grep/cli (both devDependencies, not shipped in the app bundle). Their install scripts are disabled via Lavamoat allowScripts: false (they work without them).

Validation gate (this ticket's core deliverable): ran instrument on pilot areas receive + notifications (throwaway, reverted) → 59.3% hit-rate, 45.8% false-positive rate, plus behavior-breaking string corruption and foundation-duplicating scaffolding. Decision: fall back to ast-grep/ts-morph for the wrap; retain i18next-cli for extract + types (identical JSON output → Crowdin parity holds). Full report in the ticket comment + design doc.

Screenshots/Videos

N/A — tooling-only change with no UI/runtime surface (the only runtime touch is the returnEmptyString fallback config, which has no visible effect until the sweep adds translatable keys).

Testing

Dev Testing — tooling-only, so no in-app QA. Verify from a clean checkout of this branch (monorepo root unless noted):

# 1. Install + setup must succeed (Lavamoat allow-scripts policy for the new devDeps)
yarn install && yarn setup
#    -> no "@lavamoat/allow-scripts has detected dependencies without configuration"

# 2. Lockfile consistent
yarn install --immutable            # -> no YN0028

# 3. Extraction is non-destructive (seed keys preserved)
yarn core i18n:extract
node -e "const j=require('./packages/core-mobile/app/i18n/locales/en-US/translation.json'); console.log(Object.keys(j).length, ['Settings','Send','Receive','Account'].every(k=>k in j))"
#    -> 4 true

# 4. Types generate + compile; key typing enforced (t('Settings') ok, t('nope') is a compile error)
yarn core i18n:types && yarn core tsc

# 5. CI staleness gate: exits 0 when current; add a t('New') call and re-run -> non-zero
yarn core i18n:check

# 6. ast-grep rules flag missed patterns, report-only (no file edits)
cd packages/core-mobile && ./node_modules/.bin/ast-grep scan -c sgconfig.yml app/new/features/notifications

# 7. i18n unit tests still pass (returnEmptyString change)
yarn core test app/i18n

Jira ticket moved to Testing.

Build Numbers

• iOS: 9403
• Android: 9404
• Pipeline: https://app.bitrise.io/app/7d7ca5af7066e290/pipelines/c9c34e44-f7ad-4e57-bb55-e28a227e9a68

Checklist

• I have performed a self-review of my code
• I have verified the code works
• I have included screenshots / videos of android and ios (N/A — no UI)
• I have added testing steps
• I have added/updated necessary unit tests (i18n foundation tests pass with the runtime change)
• I have updated the documentation (design doc + report in Obsidian; Jira comment)

[Copilot]

Pull request overview

Adds the initial i18n string-extraction/tooling pipeline for @avalabs/core-mobile, centered on i18next-cli (extract + type generation) with an ast-grep ruleset to report hardcoded user-facing strings that automated instrumentation may miss. Also adjusts the i18n runtime to treat empty-string translations as missing so non-EN catalogs seeded with "" fall back to English.

Changes:

• Introduces i18next-cli config + workspace scripts for extract, types, and CI staleness checks.
• Adds ast-grep configuration and rules for reporting likely user-facing hardcoded strings (JSX props, snackbar/alert args, accessibility labels).
• Updates i18n runtime behavior (returnEmptyString: false) and commits updated locale catalogs + generated TS resource typings.

Reviewed changes

Copilot reviewed 18 out of 21 changed files in this pull request and generated 3 comments.

Show a summary per file

File	Description
yarn.lock	Adds lockfile entries for i18next-cli, @ast-grep/cli, and their transitive deps.
packages/core-mobile/package.json	Adds i18n scripts and devDependencies (i18next-cli, @ast-grep/cli), plus Lavamoat allow-scripts entries.
packages/core-mobile/i18next.config.ts	New i18next-cli configuration (locales, extract/output behavior, types output).
packages/core-mobile/sgconfig.yml	New ast-grep config pointing to rule directory.
packages/core-mobile/scripts/i18n/rules/snackbar-alert-args.yml	New ast-grep rule flagging hardcoded strings in showSnackbar/showAlert calls.
packages/core-mobile/scripts/i18n/rules/jsx-string-props.yml	New ast-grep rule flagging hardcoded strings in common JSX props.
packages/core-mobile/scripts/i18n/rules/accessibility-labels.yml	New ast-grep rule flagging hardcoded accessibilityLabel/accessibilityHint.
packages/core-mobile/app/i18n/index.ts	Runtime change: treat "" as missing via returnEmptyString: false.
packages/core-mobile/app/i18n/@types/resources.d.ts	Generated TS resource types from the EN catalog.
packages/core-mobile/app/i18n/@types/i18next.d.ts	Module augmentation to bind generated resources to i18next typing.
packages/core-mobile/app/i18n/locales/en-US/translation.json	Updates/extends seed translation catalog (adds Account, reorders keys).
packages/core-mobile/app/i18n/locales/zh-CN/translation.json	Updates/extends seed translation catalog (adds Account, reorders keys).
packages/core-mobile/app/i18n/locales/zh-TW/translation.json	Updates/extends seed translation catalog (adds Account, reorders keys).
packages/core-mobile/app/i18n/locales/fr-FR/translation.json	Updates/extends seed translation catalog (adds Account, reorders keys).
packages/core-mobile/app/i18n/locales/de-DE/translation.json	Updates/extends seed translation catalog (adds Account, reorders keys).
packages/core-mobile/app/i18n/locales/hi-IN/translation.json	Updates/extends seed translation catalog (adds Account, reorders keys).
packages/core-mobile/app/i18n/locales/ja-JP/translation.json	Updates/extends seed translation catalog (adds Account, reorders keys).
packages/core-mobile/app/i18n/locales/ko-KR/translation.json	Updates/extends seed translation catalog (adds Account, reorders keys).
packages/core-mobile/app/i18n/locales/ru-RU/translation.json	Updates/extends seed translation catalog (adds Account, reorders keys).
packages/core-mobile/app/i18n/locales/es-ES/translation.json	Updates/extends seed translation catalog (adds Account, reorders keys).
packages/core-mobile/app/i18n/locales/tr-TR/translation.json	Updates/extends seed translation catalog (adds Account, reorders keys).

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[github-actions]

Coverage report ✅

2/2 packages passed thresholds
Thresholds are shown inline against each package baseline.

🟢 @avalabs/core-mobile

St.	Category	Percentage	Covered / Total
🟢	Statements	27.86% (+9.86% vs 18% ▲)	12318/44213
🟢	Branches	23.48% (+11.48% vs 12% ▲)	6033/25687
🟢	Functions	22.13% (+9.13% vs 13% ▲)	2261/10216
🟢	Lines	27.94% (+9.94% vs 18% ▲)	11796/42219

🟢 @avalabs/k2-alpine

St.	Category	Percentage	Covered / Total
🟢	Statements	8.49% (+6.49% vs 2% ▲)	304/3578
🟢	Branches	7.90% (+6.90% vs 1% ▲)	172/2177
🟢	Functions	4.99% (+3.99% vs 1% ▲)	41/821
🟢	Lines	7.82% (+5.82% vs 2% ▲)	257/3283

Artifacts and threshold sources

• @avalabs/core-mobile: summary core-mobile/coverage/coverage-summary.json, thresholds core-mobile/coverage-thresholds.json
• @avalabs/k2-alpine: summary k2-alpine/coverage/coverage-summary.json, thresholds k2-alpine/coverage-thresholds.json

Source run: Mobile PR

[Copilot]

Pull request overview

Copilot reviewed 19 out of 22 changed files in this pull request and generated no new comments.

[Copilot]

Pull request overview

Copilot reviewed 20 out of 23 changed files in this pull request and generated 2 comments.

[B0Y3R-AVA]

Adversarial review (two independent passes, findings verified against i18next-cli v1.66.2 source, this branch, and the yarn.lock diff). No blockers for a tooling-only PR — overall this is in good shape and the config comments match upstream behavior (defaultValue arg order, extract --ci, instrument --dry-run, sorted/idempotent extraction all check out). Four substantive comments inline (.ts files invisible to the snackbar rule, missing nsSeparator in the type augmentation, types.output collision quirk, CI gate coverage/wiring), plus a couple of minor notes.

Minor (no inline anchor):

• The i18n-jsx-string-prop rule will flag non-user-facing title/label/message/description strings too (analytics payloads, dev-only props) — acceptable noise for report-only, just calibrating expectations for the sweep.
• Verified @swc/core genuinely arrives via i18next-cli / i18next-resources-for-ts in the lockfile (real new transitive dep, and it does ship a postinstall), so an allowScripts entry is needed — see inline note on the path naming.

[Copilot]

Pull request overview

Copilot reviewed 21 out of 24 changed files in this pull request and generated no new comments.

[Copilot]

Pull request overview

Copilot reviewed 21 out of 24 changed files in this pull request and generated 1 comment.