hirasso · hirasso · Aug 9, 2025 · Aug 9, 2025 · Aug 9, 2025 · Aug 9, 2025
diff --git a/.changeset/hip-memes-beam.md b/.changeset/hip-memes-beam.md
@@ -0,0 +1,5 @@
+---
+"@hirasso/restore-scroll": patch
+---
+
+Check types during unit tests
diff --git a/.changeset/mean-baboons-leave.md b/.changeset/mean-baboons-leave.md
@@ -0,0 +1,5 @@
+---
+"@hirasso/restore-scroll": patch
+---
+
+Resolve `<body>` to the root scrolling element
diff --git a/.github/PULL_REQUEST_TEMPLATE.md b/.github/PULL_REQUEST_TEMPLATE.md
@@ -18,7 +18,6 @@ Make sure the PR fulfills as many of the following requirements as possible
 
 - [ ] The PR is submitted to the `main` branch
 - [ ] The code was formatted before pushing (`pnpm run format`)
-- [ ] All tests are passing (`pnpm run test`)
 - [ ] New or updated tests are included
 - [ ] The documentation was updated as required
 

diff --git a/.github/workflows/unit-tests.yml b/.github/workflows/unit-tests.yml
@@ -34,5 +34,8 @@ jobs:
       - name: Build
         run: pnpm run build
 
+      - name: Typecheck
+        run: pnpm run typecheck
+
       - name: Run tests
         run: pnpm run test:unit
diff --git a/.lintstagedrc.js b/.lintstagedrc.js
@@ -1,4 +1,4 @@
 export default {
-  "**/*.{js,ts,mjs}": ["prettier --write"],
+  "**/*.{js,ts,mjs}": ["pnpm run format"],
   "**/*.astro": ["astro check"],
 };
diff --git a/package.json b/package.json
@@ -43,7 +43,8 @@
     "test:unit:watch": "vitest --config ./tests/unit/vitest.config.ts",
     "test:e2e": "pnpm exec playwright test --config ./tests/e2e/config.playwright.ts",
     "test:e2e:dev": "PLAYWRIGHT_ENV=dev pnpm run test:e2e --ui",
-    "test:e2e:install": "pnpm exec playwright install --with-deps"
+    "test:e2e:install": "pnpm exec playwright install --with-deps",
+    "typecheck": "tsc --noEmit"
   },
   "devDependencies": {
     "@changesets/cli": "^2.28.1",

diff --git a/src/env.ts b/src/env.ts
diff --git a/src/helpers.ts b/src/helpers.ts
@@ -149,7 +149,7 @@ export function createContainerSelector(
 /**
  * Check if an element is a root element (<html> or <body>)
  */
-export function isRootElement(element: Element): boolean {
+export function isRootElement(element: unknown): boolean {
   return (
     element instanceof HTMLHtmlElement || element instanceof HTMLBodyElement
   );
@@ -206,8 +206,9 @@ export function commitScrollState(state: ScrollState) {
  * Resolve a target
  */
 export function resolveTarget(target: Target | null): Element | null {
-  /** The window */
-  if (target === window) {
+  if (!target) return null;
+
+  if (target === window || isRootElement(target)) {
     return document.scrollingElement ?? document.documentElement;
   }
 

diff --git a/tests/unit/tests/resolveTarget.test.ts b/tests/unit/tests/resolveTarget.test.ts
@@ -17,6 +17,10 @@ describe("resolveTarget", () => {
     expect(resolveTarget(window)).toEqual(document.documentElement);
   });
 
+  it("resolves the <body> to the document root", () => {
+    expect(resolveTarget(document.body)).toEqual(document.documentElement);
+  });
+
   it("Returns either an element or nothing", () => {
     const existing = document.querySelector(".foo");
     const missing = document.querySelector(".waldo");