likern · likern · Jan 6, 2022 · Jan 6, 2022 · Jan 6, 2022 · Jan 6, 2022
diff --git a/.eslintignore b/.eslintignore
@@ -0,0 +1,2 @@
+node_modules/
+lib/
diff --git a/.eslintrc.js b/.eslintrc.js
@@ -0,0 +1,22 @@
+/* eslint-disable no-undef */
+module.exports = {
+  root: true,
+  parser: "@typescript-eslint/parser",
+  parserOptions: {
+    ecmaVersion: 2021,
+    sourceType: "module",
+    allowReserved: false,
+  },
+  env: {
+    es2021: true,
+  },
+  plugins: ["@typescript-eslint"],
+  extends: [
+    "eslint:recommended",
+    "plugin:@typescript-eslint/eslint-recommended",
+    "plugin:@typescript-eslint/recommended",
+  ],
+  rules: {
+    "@typescript-eslint/no-inferrable-types": "off",
+  },
+};
diff --git a/@types/intl.d.ts b/@types/intl.d.ts
@@ -0,0 +1,108 @@
+/// <reference no-default-lib="true"/>
+
+declare namespace Intl {
+  /**
+   * The locale matching algorithm to use.
+   *
+   * [MDN](https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/Intl#Locale_negotiation).
+   */
+  type ListFormatLocaleMatcher = "lookup" | "best fit";
+
+  /**
+   * The format of output message.
+   *
+   * [MDN](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Intl/ListFormat/ListFormat#parameters).
+   */
+  type ListFormatType = "conjunction" | "disjunction" | "unit";
+
+  /**
+   * The length of the formatted message.
+   *
+   * [MDN](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Intl/ListFormat/ListFormat#parameters).
+   */
+  type ListFormatStyle = "long" | "short" | "narrow";
+
+  /**
+   * An object with some or all properties of the `Intl.ListFormat` constructor `options` parameter.
+   *
+   * [MDN](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Intl/ListFormat/ListFormat#parameters).
+   */
+  interface ListFormatOptions {
+    /** The locale matching algorithm to use. For information about this option, see [Intl page](https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/Intl#Locale_negotiation). */
+    localeMatcher?: ListFormatLocaleMatcher;
+    /** The format of output message. */
+    type?: ListFormatType;
+    /** The length of the internationalized message. */
+    style?: ListFormatStyle;
+  }
+
+  interface ListFormat {
+    /**
+     * Returns a string with a language-specific representation of the list.
+     *
+     * @param list - An iterable object, such as an [Array](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Array).
+     *
+     * @throws `TypeError` if `list` includes something other than the possible values.
+     *
+     * @returns {string} A language-specific formatted string representing the elements of the list.
+     *
+     * [MDN](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Intl/ListFormat/format).
+     */
+    format(list: Iterable<string>): string;
+
+    /**
+     * Returns an Array of objects representing the different components that can be used to format a list of values in a locale-aware fashion.
+     *
+     * @param list - An iterable object, such as an [Array](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Array), to be formatted according to a locale.
+     *
+     * @throws `TypeError` if `list` includes something other than the possible values.
+     *
+     * @returns {{ type: "element" | "literal", value: string; }[]} An Array of components which contains the formatted parts from the list.
+     *
+     * [MDN](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Intl/ListFormat/formatToParts).
+     */
+    formatToParts(list: Iterable<string>): { type: "element" | "literal"; value: string }[];
+  }
+
+  const ListFormat: {
+    prototype: ListFormat;
+
+    /**
+     * Creates [Intl.ListFormat](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Intl/ListFormat) objects that
+     * enable language-sensitive list formatting.
+     *
+     * @param locales - A string with a [BCP 47 language tag](http://tools.ietf.org/html/rfc5646), or an array of such strings.
+     *  For the general form and interpretation of the `locales` argument,
+     *  see the [`Intl` page](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Intl#Locale_identification_and_negotiation).
+     *
+     * @param options - An [object](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Intl/ListFormat/ListFormat#parameters)
+     *  with some or all options of `ListFormatOptions`.
+     *
+     * @returns [Intl.ListFormatOptions](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Intl/ListFormat) object.
+     *
+     * [MDN](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Intl/ListFormat).
+     */
+    new (locales?: BCP47LanguageTag | BCP47LanguageTag[], options?: ListFormatOptions): ListFormat;
+
+    /**
+     * Returns an array containing those of the provided locales that are
+     * supported in list formatting without having to fall back to the runtime's default locale.
+     *
+     * @param locales - A string with a [BCP 47 language tag](http://tools.ietf.org/html/rfc5646), or an array of such strings.
+     *  For the general form and interpretation of the `locales` argument,
+     *  see the [`Intl` page](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Intl#Locale_identification_and_negotiation).
+     *
+     * @param options - An [object](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Intl/ListFormat/supportedLocalesOf#parameters).
+     *  with some or all possible options.
+     *
+     * @returns An array of strings representing a subset of the given locale tags that are supported in list
+     *  formatting without having to fall back to the runtime's default locale.
+     *
+     * [MDN](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Intl/ListFormat/supportedLocalesOf).
+     */
+    supportedLocalesOf(
+      locales: BCP47LanguageTag | BCP47LanguageTag[],
+      options?: Pick<ListFormatOptions, "localeMatcher">
+    ): BCP47LanguageTag[];
+  };
+}
diff --git a/configs/typescript/tsconfig.mobile.json b/configs/typescript/tsconfig.mobile.json
@@ -0,0 +1,7 @@
+{
+  "extends": "./tsconfig.package.json",
+  "compilerOptions": {
+    "noEmit": true,
+    "composite": true
+  }
+}
diff --git a/configs/typescript/tsconfig.package.json b/configs/typescript/tsconfig.package.json
@@ -0,0 +1,33 @@
+{
+  "compilerOptions": {
+    "baseUrl": ".",
+    "declaration": true,
+    "declarationMap": true,
+    "sourceMap": true,
+    "skipLibCheck": true,
+    "esModuleInterop": true,
+    "allowSyntheticDefaultImports": true,
+    "module": "ES2020",
+    "moduleResolution": "node",
+    "resolveJsonModule": true,
+    "target": "esnext",
+    "lib": [
+      "ES2021"
+    ],
+    "jsx": "react-jsx",
+    "composite": true,
+    "strict": true,
+    "allowUnreachableCode": false,
+    "allowUnusedLabels": false,
+    "forceConsistentCasingInFileNames": true,
+    "noFallthroughCasesInSwitch": true,
+    "noImplicitReturns": true,
+    "noImplicitUseStrict": false,
+    "noStrictGenericChecks": false,
+    "noUnusedLocals": true,
+    "noUnusedParameters": true,
+    "isolatedModules": true,
+    "preserveValueImports": true,
+    "importsNotUsedAsValues": "error"
+  }
+}
diff --git a/package.json b/package.json
@@ -47,6 +47,7 @@
     "prettier": "^2.3.2",
     "rollup": "^2.52.7",
     "rollup-plugin-terser": "^7.0.2",
+    "typescript": "=4.5.4",
     "uglify-js": "^3.13.10"
   },
   "main": "build/node/luxon.js",

diff --git a/src/datetime.js → src/datetime.ts b/src/datetime.js → src/datetime.ts