Add TypeScript types (#58) (h/t @Phillip9587)

index.d.ts

@@ -0,0 +1,59 @@
+import { IControl, Map, Style } from "mapbox-gl";
+
+/** Options to configure the Mapbox GL Language plugin. */
+export declare interface MapboxLanguageOptions {
+  /** List of supported languages */
+  supportedLanguages?: string[];
+  /** Custom style transformation to apply */
+  languageTransform?: (style: Style, language: string) => Style;
+  /**
+   * RegExp to match if a text-field is a language field
+   * @default /^name_/
+   */
+  languageField?: RegExp;
+  /** Given a language choose the field in the vector tiles */
+  getLanguageField?: (language: string) => string;
+  /** Name of the source that contains the different languages. */
+  languageSource?: string;
+  /** Name of the default language to initialize style after loading. */
+  defaultLanguage?: string;
+  /** Name of the layers that should be excluded from translation. */
+  excludedLayerIds?: string[];
+}
+
+declare class MapboxLanguage implements IControl {
+  /**
+   * Create a new [Mapbox GL JS plugin](https://www.mapbox.com/blog/build-mapbox-gl-js-plugins/) that
+   * modifies the layers of the map style to use the `text-field` that matches the browser language.
+   * As of Mapbox GL Language v1.0.0, this plugin no longer supports token values (e.g. `{name}`). v1.0+ expects the `text-field`
+   * property of a style to use an [expression](https://docs.mapbox.com/mapbox-gl-js/style-spec/expressions/) of the form `['get', 'name_en']` or `['get', 'name']`; these expressions can be nested. Note that `get` expressions used as inputs to other expressions may not be handled by this plugin. For example:
+   * ```
+   * ["match",
+   *   ["get", "name"],
+   *   "California",
+   *   "Golden State",
+   *   ["coalesce",
+   *     ["get", "name_en"],
+   *     ["get", "name"]
+   *   ]
+   * ]
+   * ```
+   * Only styles based on [Mapbox v8 styles](https://docs.mapbox.com/help/troubleshooting/streets-v8-migration-guide/) are supported.
+   *
+   * @constructor
+   * @param options Options to configure the plugin.
+   */
+  constructor(options?: MapboxLanguageOptions);
+
+  onAdd(map: Map): HTMLElement;
+  onRemove(map: Map): void;
+
+  /**
+   * Explicitly change the language for a style.
+   * @param style Mapbox GL style to modify
+   * @param language The language iso code
+   */
+  setLanguage(style: Style, language: string): Style;
+}
+
+export default MapboxLanguage;

package.json

@@ -3,6 +3,7 @@
   "version": "1.0.0",
   "description": "Mapbox GL JS plugin for switching map language to the browser language.",
   "main": "index.js",
+  "types": "index.d.ts",
   "scripts": {
     "lint": "eslint index.js test/*.js",
     "pretest": "npm run lint",
@@ -38,6 +39,9 @@
     "mapbox-gl": ">=0.29.0"
   },
   "eslintConfig": {
+    "ignorePatterns": [
+      "*.d.ts"
+    ],
     "parserOptions": {
       "sourceType": "module"
     },