test: Add scroll test

Author: franky47

packages/e2e/next/cypress/e2e/shared/scroll.cy.ts

@@ -0,0 +1,11 @@
+import { testScroll } from 'e2e-shared/specs/scroll.cy'
+
+testScroll({
+  path: '/app/scroll',
+  nextJsRouter: 'app'
+})
+
+testScroll({
+  path: '/pages/scroll',
+  nextJsRouter: 'pages'
+})

packages/e2e/next/src/app/app/(shared)/scroll/page.tsx

@@ -0,0 +1,10 @@
+import { Scroll } from 'e2e-shared/specs/scroll'
+import { Suspense } from 'react'
+
+export default function Page() {
+  return (
+    <Suspense>
+      <Scroll />
+    </Suspense>
+  )
+}

packages/e2e/next/src/pages/pages/scroll.tsx

@@ -0,0 +1,3 @@
+import { Scroll } from 'e2e-shared/specs/scroll'
+
+export default Scroll

packages/e2e/react-router/v6/cypress/e2e/shared/scroll.cy.ts

@@ -0,0 +1,3 @@
+import { testScroll } from 'e2e-shared/specs/scroll.cy'
+
+testScroll({ path: '/scroll' })

packages/e2e/react-router/v6/src/react-router.tsx

@@ -45,6 +45,7 @@ const router = createBrowserRouter(
       <Route path="fog-of-war/result"                     lazy={load(import('./routes/fog-of-war.result'))} />
       <Route path="conditional-rendering/useQueryState"   lazy={load(import('./routes/conditional-rendering.useQueryState'))} />
       <Route path="conditional-rendering/useQueryStates"  lazy={load(import('./routes/conditional-rendering.useQueryStates'))} />
+      <Route path="scroll"                                lazy={load(import('./routes/scroll'))} />
 
       <Route path="render-count/:hook/:shallow/:history/:startTransition/no-loader"     lazy={load(import('./routes/render-count.$hook.$shallow.$history.$startTransition.no-loader'))} />
       <Route path="render-count/:hook/:shallow/:history/:startTransition/sync-loader"   lazy={load(import('./routes/render-count.$hook.$shallow.$history.$startTransition.sync-loader'))} />

packages/e2e/react-router/v6/src/routes/scroll.tsx

@@ -0,0 +1,3 @@
+import { Scroll } from 'e2e-shared/specs/scroll'
+
+export default Scroll

packages/e2e/react-router/v7/app/routes.ts

@@ -28,6 +28,7 @@ export default [
     route('/fog-of-war/result',                     './routes/fog-of-war.result.tsx'),
     route('/conditional-rendering/useQueryState',   './routes/conditional-rendering.useQueryState.tsx'),
     route('/conditional-rendering/useQueryStates',  './routes/conditional-rendering.useQueryStates.tsx'),
+    route('/scroll',                                './routes/scroll.tsx'),
 
     route('/render-count/:hook/:shallow/:history/:startTransition/no-loader',    './routes/render-count.$hook.$shallow.$history.$startTransition.no-loader.tsx'),
     route('/render-count/:hook/:shallow/:history/:startTransition/sync-loader',  './routes/render-count.$hook.$shallow.$history.$startTransition.sync-loader.tsx'),

packages/e2e/react-router/v7/app/routes/scroll.tsx

@@ -0,0 +1,3 @@
+import { Scroll } from 'e2e-shared/specs/scroll'
+
+export default Scroll

packages/e2e/react-router/v7/cypress/e2e/shared/scroll.cy.ts

@@ -0,0 +1,3 @@
+import { testScroll } from 'e2e-shared/specs/scroll.cy'
+
+testScroll({ path: '/scroll' })

packages/e2e/react/cypress/e2e/shared/scroll.cy.ts

@@ -0,0 +1,3 @@
+import { testScroll } from 'e2e-shared/specs/scroll.cy'
+
+testScroll({ path: '/scroll' })

packages/e2e/react/src/routes.tsx

@@ -23,6 +23,7 @@ const routes: Record<string, React.LazyExoticComponent<() => JSX.Element>> = {
   '/referential-stability/useQueryStates':  lazy(() => import('./routes/referential-stability.useQueryStates')),
   '/conditional-rendering/useQueryState':   lazy(() => import('./routes/conditional-rendering.useQueryState')),
   '/conditional-rendering/useQueryStates':  lazy(() => import('./routes/conditional-rendering.useQueryStates')),
+  '/scroll':                                lazy(() => import('./routes/scroll')),
 
   '/render-count/useQueryState/true/replace/false':   lazy(() => import('./routes/render-count')),
   '/render-count/useQueryState/true/replace/true':    lazy(() => import('./routes/render-count')),

packages/e2e/react/src/routes/scroll.tsx

@@ -0,0 +1,3 @@
+import { Scroll } from 'e2e-shared/specs/scroll'
+
+export default Scroll

packages/e2e/remix/app/routes/scroll.tsx

@@ -0,0 +1,3 @@
+import { Scroll } from 'e2e-shared/specs/scroll'
+
+export default Scroll

packages/e2e/remix/cypress/e2e/shared/scroll.cy.ts

@@ -0,0 +1,3 @@
+import { testScroll } from 'e2e-shared/specs/scroll.cy'
+
+testScroll({ path: '/scroll' })

packages/e2e/shared/specs/scroll.cy.ts

@@ -0,0 +1,18 @@
+import { createTest } from '../create-test'
+
+export const testScroll = createTest('scroll', ({ path }) => {
+  it('does not scroll to the top of the page by default (scroll: false)', () => {
+    cy.visit(path + '?scroll=false')
+    cy.contains('#hydration-marker', 'hydrated').should('be.hidden')
+    cy.get('#not-at-the-top').should('be.visible')
+    cy.get('button').click()
+    cy.get('#not-at-the-top').should('be.visible')
+  })
+  it('scrolls to the top of the page when setting scroll: true', () => {
+    cy.visit(path + '?scroll=true')
+    cy.contains('#hydration-marker', 'hydrated').should('be.hidden')
+    cy.get('#not-at-the-top').should('be.visible')
+    cy.get('button').click()
+    cy.get('#at-the-top').should('be.visible')
+  })
+})

packages/e2e/shared/specs/scroll.tsx

@@ -0,0 +1,56 @@
+'use client'
+
+import { parseAsBoolean, useQueryState } from 'nuqs'
+import { useEffect, useState } from 'react'
+
+export function Scroll() {
+  return (
+    <>
+      <ScrollDetector />
+      <div style={{ height: '200vh' }} />
+      <ScrollAction />
+    </>
+  )
+}
+
+function ScrollDetector() {
+  const [atTheTop, setAtTheTop] = useState(false)
+
+  useEffect(() => {
+    const controller = new AbortController()
+    window.addEventListener('scroll', () => setAtTheTop(window.scrollY === 0), {
+      signal: controller.signal
+    })
+    return () => controller.abort()
+  }, [])
+
+  return (
+    <span
+      id={atTheTop ? 'at-the-top' : 'not-at-the-top'}
+      style={{ position: 'fixed', top: 8 }}
+    >
+      {atTheTop ? null : 'not '}at the top
+    </span>
+  )
+}
+
+function ScrollAction() {
+  const [scroll] = useQueryState('scroll', parseAsBoolean.withDefault(false))
+  const [, setState] = useQueryState('test', {
+    scroll
+  })
+
+  useEffect(() => {
+    document.getElementById('scroll-to-me')?.scrollIntoView()
+  }, [])
+
+  return (
+    <button
+      id="scroll-to-me"
+      onClick={() => setState('pass')}
+      style={{ marginInline: 'auto', display: 'block' }}
+    >
+      Test
+    </button>
+  )
+}