Try out a new way to build declarations

ember-primitives/package.json

@@ -85,7 +85,8 @@
     "publint": "^0.3.17",
     "rollup": "^4.57.1",
     "rollup-plugin-copy": "^3.5.0",
-    "typescript": "^6.0.2"
+    "typescript": "^6.0.2",
+    "unplugin-isolated-decl": "^0.16.0"
   },
   "publishConfig": {
     "registry": "https://registry.npmjs.org"

ember-primitives/rollup.config.mjs

@@ -1,5 +1,6 @@
 import { Addon } from "@embroider/addon-dev/rollup";
 
+import UnpluginIsolatedDecl from "unplugin-isolated-decl/rollup";
 import { babel } from "@rollup/plugin-babel";
 import copy from "rollup-plugin-copy";
 
@@ -35,10 +36,19 @@ export default {
     babel({ extensions, babelHelpers: "inline" }),
     addon.gjs(),
     addon.keepAssets(["**/*.css"]),
-    addon.declarations(
-      "declarations",
-      "pnpm ember-tsc --declaration --declarationDir declarations",
-    ),
+    UnpluginIsolatedDecl({
+      include: ["**/*.{ts,gts}"],
+      transformer: "oxc",
+      extraOutDir: "declarations",
+      transformOptions: {
+        stripInternal: true,
+        sourcemap: true,
+      },
+    }),
+    // addon.declarations(
+    //   "declarations",
+    //   "pnpm ember-tsc --declaration --declarationDir declarations",
+    // ),
     addon.clean(),
     copy({
       targets: [

ember-primitives/src/head.gts

@@ -9,7 +9,7 @@ export interface Signature {
   };
 }
 
-function getHead() {
+function getHead(): HTMLHeadElement {
   return document.head;
 }
 

ember-primitives/src/helpers/body-class.ts

@@ -43,7 +43,7 @@ function queueUpdate() {
  *
  * Folks can set classes in their html and we don't want to mess with those
  */
-function updateBodyClass() {
+function updateBodyClass(): void {
   const toAdd = classNames();
 
   for (const name of previousRegistrations) {

ember-primitives/src/iframe.ts

@@ -11,7 +11,7 @@
  * </template>
  * ```
  */
-export const inIframe = () => window.self !== window.top;
+export const inIframe: () => boolean = () => window.self !== window.top;
 
 /**
  * Returns true if the current frame is not within an iframe.
@@ -28,4 +28,4 @@ export const inIframe = () => window.self !== window.top;
  * </template>
  * ```
  */
-export const notInIframe = () => !inIframe();
+export const notInIframe: () => boolean = () => !inIframe();

ember-primitives/src/on-resize.ts

@@ -32,7 +32,7 @@ class OnResize extends Modifier<Signature> {
   #callback: ((entry: ResizeObserverEntry) => void) | null = null;
   #element: Element | null = null;
 
-  #resizeObserver = resizeObserver(this);
+  #resizeObserver: ReturnType<typeof resizeObserver> = resizeObserver(this);
 
   constructor(owner: Owner, args: ArgsFor<Signature>) {
     super(owner, args);
@@ -44,7 +44,7 @@ class OnResize extends Modifier<Signature> {
     });
   }
 
-  modify(element: Element, [callback]: [callback: (entry: ResizeObserverEntry) => void]) {
+  modify(element: Element, [callback]: [callback: (entry: ResizeObserverEntry) => void]): void {
     assert(
       `{{onResize}}: callback must be a function, but was ${callback as unknown as string}`,
       typeof callback === 'function'

ember-primitives/tsconfig.json

@@ -2,6 +2,8 @@
   "extends": "@ember/library-tsconfig",
   "include": ["src/**/*", "unpublished-development-types/**/*"],
   "compilerOptions": {
+    "isolatedDeclarations": true,
+    "erasableSyntaxOnly": true,
     "rootDir": "./src",
     "types": ["ember-source/types", "@glint/ember-tsc/types"]
   }