Prettier Plugin

prettier-plugin-intlayer puts the keys of your translations in a fixed order every time Prettier formats a file. Diffs stay small, merge conflicts get rarer and a missing locale is easy to spot.

// before
t({ en: "Hello", ru: "Привет", fr: "Bonjour", "en-GB": "Hello", ar: "مرحبا" });

// after
t({ en: "Hello", ar: "مرحبا", "en-GB": "Hello", fr: "Bonjour", ru: "Привет" });

Installation

npm install --save-dev prettier prettier-plugin-intlayer

Requires Prettier 3 or later.

If your project already uses Prettier, intlayer init prettier installs the plugin and adds it to your config for you.

Usage

Add the plugin to your Prettier config:

{
  "plugins": ["prettier-plugin-intlayer"]
}

To apply it to your content declarations only, use an override:

{
  "overrides": [
    {
      "files": "*.content.{ts,tsx,js,jsx,mjs,cjs,json}",
      "options": {
        "plugins": ["prettier-plugin-intlayer"],
        "intlayerSortContentKeys": true
      }
    }
  ]
}

What gets sorted

t(): locales

The pinned locales come first (en by default). The other locales follow in alphabetical order.

t({
  en: "Invitation not found",
  ar: "الدعوة غير موجودة",
  de: "Einladung nicht gefunden",
  "en-GB": "Invitation not found",
  fr: "Invitation introuvable",
  "he-IL": "ההזמנה לא נמצאה",
});

plural(): CLDR order

Categories go from the smallest quantity to the fallback: zero, one, two, few, many, other.

plural({
  one: "{{count}} вакансия",
  few: "{{count}} вакансии",
  many: "{{count}} вакансий",
  other: "{{count}} вакансий",
});

enu(): ascending thresholds

Conditions are sorted by their number, then by operator (<1, <=1, 1, >=1, >1). fallback goes last.

enu({
  "<-1": "Less than minus one car",
  "0": "No cars",
  "2": "Two cars",
  ">=3": "Many cars",
  fallback: "Some cars",
});

At runtime, the first matching condition wins. The plugin applies the new order only when every quantity still resolves to the same content. When order decides the result, the object is left as written. For example, in { '<1': …, '<=-2.3': … } the '<1' key catches every negative number.

select(): alphabetical

Cases are sorted alphabetically and fallback goes last.

select({
  draft: "This post is a draft",
  published: "This post is live",
  scheduled: "This post is scheduled",
  fallback: "Unknown status",
});

Without a fallback or an other key, the last case is used as the fallback. That case stays last and only the cases before it are sorted.

.content.json files

The serialized form is sorted the same way: { "nodeType": "translation", "translation": { … } }, as well as plural, enumeration and select nodes.

Identical translations

In *.content.* files, a t() whose locales all hold the same string is replaced by that string. A plain string is served to every locale, so the output does not change.

// before
nextjs: t({ en: "Next.js", fr: "Next.js", es: "Next.js" }),

// after
nextjs: "Next.js",

A t() with a single locale, a type argument (t<string>()), a comment or non-string values is kept. Set intlayerCollapseIdenticalTranslations: false to turn it off.

Content keys (opt-in)

With intlayerSortContentKeys: true, the plugin also sorts the keys of the dictionary content alphabetically, at every nesting level. This applies only in *.content.* files.

export default {
  key: "app",
  content: {
    description: t({ en: "…", fr: "…" }),
    footer: {
      copyright: "© Intlayer",
      links: [{ href: "/doc", label: t({ en: "Docs", fr: "Docs" }) }],
    },
    title: t({ en: "Hello", fr: "Bonjour" }),
  },
} satisfies Dictionary;

The sort continues through every helper (t, plural, enu, select, cond, gender, md, insert, nest, file…) to reach the objects inside them. Each helper's own key map keeps its ordering. The keys passed to cond() and gender() are never reordered, because their last key is the fallback. The fields next to content (key, title, locale…) stay as they are.

Options

What is left untouched

• Objects holding a spread (...base), a computed key ([key]), a method or a duplicated key.
• plural() maps with a key that is not a CLDR category.
• enu() maps whose new order would change the resolved content.
• Calls to any other function named like a helper but given a non-object argument.

Comments move with the key they belong to.

Supported parsers

babel, babel-flow, babel-ts, typescript, flow, acorn, espree, meriyah, json, json5 and jsonc. The <script> blocks of Vue, Svelte and Astro files are formatted with these parsers.

Known limitation. Prettier runs a single plugin per parser. If another plugin also replaces the JavaScript/TypeScript parsers (for example prettier-plugin-tailwindcss), only the last one listed applies to those files. Scope prettier-plugin-intlayer to *.content.* files with an override to avoid the conflict.