feat: Preserve locale with cookie & react-intl

[canerakdas]

This PR aims to preserve the current language across navigation between nodejs.org and learn pages if the NEXT_LOCALE cookie is present.

[vercel]

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Project	Deployment	Actions	Updated (UTC)
nodejs-learn	Ready	Preview	Apr 26, 2026 11:04am

[cursor]

PR Summary

Medium Risk
Updates global layout/nav to rewrite navigation links based on the NEXT_LOCALE cookie, which can affect routing and cross-site navigation behavior. Risk is moderate due to new client-side cookie parsing and link localization logic but limited scope to UI navigation.

Overview
Wraps the app layout in a new LocaleProvider that detects the active locale from the NEXT_LOCALE cookie (with a defaultLocale fallback) and exposes a localizeLink helper.

Updates Navigation to memoize and render locale-adjusted navItems, and adjusts site.json by introducing defaultLocale and prefixing select navigation links with /en so they can be rewritten for other locales.

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[Copilot]

Pull request overview

Adds client-side locale detection (via NEXT_LOCALE) and uses it to localize navigation links from the Learn site back to locale-prefixed nodejs.org routes.

Changes:

• Introduces a LocaleProvider (react-intl IntlProvider) that detects locale from the NEXT_LOCALE cookie.
• Adds a link-localization utility and updates the navigation component to rewrite locale-prefixed links.
• Updates site.json navigation entries to include the default locale prefix and adds react-intl as a dependency.

Reviewed changes

Copilot reviewed 6 out of 7 changed files in this pull request and generated 5 comments.

Show a summary per file

File	Description
util/link.js	New helper to rewrite locale-prefixed internal links.
providers/LocaleProvider.jsx	New provider to source locale from NEXT_LOCALE and expose it via react-intl.
components/Navigation/index.jsx	Uses detected locale to localize nav item links.
components/Layout/index.jsx	Wraps page layout with LocaleProvider.
site.json	Adds defaultLocale and updates nav links to include /en/ prefixes.
package.json	Adds react-intl dependency.
package-lock.json	Locks new react-intl and related FormatJS dependencies.

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[cursor]

Cursor Bugbot has reviewed your changes and found 2 potential issues.

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Unmemoized context value defeats downstream useMemo

Medium Severity

The value object passed to LocaleContext.Provider is recreated on every render without useMemo, producing a new localizeLink function reference each time. This causes all context consumers to re-render on every parent render and completely defeats the useMemo in the Navigation component, which lists localizeLink as its sole dependency. The memoization in Navigation is effectively a no-op. The value needs to be wrapped in useMemo with [detectedLocale] as the dependency.

Additional Locations (1)

• components/Navigation/index.jsx#L19-L23

 

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