Add TypeScript type definitions

addon/declarations/modifiers/sortable-group.d.ts

@@ -0,0 +1,13 @@
+declare module 'ember-sortable/modifiers/sortable-group' {
+  import Modifier from 'ember-modifier';
+
+  export default class SortableGroup<T> extends Modifier<{
+    Args: {
+      Named: {
+        groupName?: string;
+        onChange: (value: T[]) => void;
+      };
+    };
+    Element: HTMLElement;
+  }> {}
+}

addon/declarations/modifiers/sortable-handle.d.ts

@@ -0,0 +1,7 @@
+declare module 'ember-sortable/modifiers/sortable-handle' {
+  import Modifier from 'ember-modifier';
+
+  export default class SortableHandle extends Modifier<{
+    Element: HTMLElement;
+  }> {}
+}

addon/declarations/modifiers/sortable-item.d.ts

@@ -0,0 +1,13 @@
+declare module 'ember-sortable/modifiers/sortable-item' {
+  import Modifier from 'ember-modifier';
+
+  export default class SortableItem extends Modifier<{
+    Args: {
+      Named: {
+        groupName?: string;
+        model: unknown;
+      };
+    };
+    Element: HTMLElement;
+  }> {}
+}

addon/declarations/test-support.d.ts

@@ -0,0 +1,8 @@
+declare module 'ember-sortable/test-support' {
+  export function drag(
+    mode: 'mouse' | 'touch',
+    itemSelector: string,
+    offsetFn: () => { dx?: number; dy?: number },
+    callbacks?: Record<string, unknown>,
+  ): unknown;
+}

test-app/app/type-tests.ts

@@ -0,0 +1,7 @@
+import sortableGroup from 'ember-sortable/modifiers/sortable-group';
+import sortableHandle from 'ember-sortable/modifiers/sortable-handle';
+import sortableItem from 'ember-sortable/modifiers/sortable-item';
+
+sortableGroup;
+sortableHandle;
+sortableItem;

test-app/package.json

@@ -13,6 +13,7 @@
     "lint:hbs:fix": "ember-template-lint . --fix",
     "lint:js": "eslint . --cache",
     "lint:js:fix": "eslint . --fix",
+    "lint:types": "glint",
     "start": "concurrently 'ember serve' 'pnpm _syncPnpm --watch' --names 'tests serve,tests sync deps'",
     "test:ember": "pnpm _syncPnpm && ember test",
     "test:all": "ember try:each"
@@ -36,6 +37,10 @@
     "@embroider/test-setup": "^2.1.1",
     "@glimmer/component": "^1.0.4",
     "@glimmer/tracking": "^1.0.4",
+    "@glint/core": "^1.4.0",
+    "@glint/environment-ember-loose": "^1.4.0",
+    "@glint/template": "^1.4.0",
+    "@tsconfig/ember": "^3.0.8",
     "babel-eslint": "^10.0.3",
     "broccoli-asset-rev": "^3.0.0",
     "ember-auto-import": "^2.4.0",
@@ -66,6 +71,7 @@
     "prettier": "^2.5.1",
     "qunit": "^2.18.0",
     "qunit-dom": "^2.0.0",
+    "typescript": "^5.5.3",
     "webpack": "^5.69.1"
   },
   "ember": {

test-app/tsconfig.json

@@ -0,0 +1,17 @@
+{
+  "extends": "@tsconfig/ember/tsconfig.json",
+  "compilerOptions": {
+    // The combination of `baseUrl` with `paths` allows Ember's classic package
+    // layout, which is not resolvable with the Node resolution algorithm, to
+    // work with TypeScript.
+    "baseUrl": ".",
+    "paths": {
+      "test-app/tests/*": ["tests/*"],
+      "test-app/*": ["app/*"],
+      "*": ["types/*"]
+    }
+  },
+  "glint": {
+    "environment": "ember-loose"
+  },
+}