AI: address issue #436

frontend/src/components/DraggableDroppableTagRow.test.tsx

@@ -1,25 +1,9 @@
-import { screen } from '@testing-library/react'
 import { beforeEach, describe, expect, it, vi } from 'vitest'
 
 import DraggableDroppableTagRow from '@/components/DraggableDroppableTagRow'
 import { buildTag } from '@/test/factories'
 import { renderWithProviders } from '@/test/render'
 
-import type { CSSProperties, ReactNode } from 'react'
-
-vi.mock ('framer-motion', async importOriginal => {
-  const original = await importOriginal<typeof import ('framer-motion')> ()
-  return {
-      ...original,
-      motion: {
-	  ...original.motion,
-	  div: ({ children, style, layoutId }: {
-	      children?: ReactNode
-	      style?: CSSProperties
-	      layoutId?: string }) => (
-	      <div style={style} data-layout-id={layoutId}>{children}</div>) } }
-})
-
 const dndKit = vi.hoisted (() => ({
   useDraggable: vi.fn (),
   useDroppable: vi.fn (),
@@ -113,32 +97,4 @@ describe ('DraggableDroppableTagRow', () => {
 	}),
     )
   })
-
-  it.each ([false, true]) (
-      'separates same-id internal and external animation identities (sp=%s)',
-      sp => {
-	const internal = buildTag ({ id: 7, name: 'internal_collision' })
-	const external = buildTag ({
-	    id: 7, name: 'nico:external_collision', category: 'nico' })
-
-	renderWithProviders (
-	    <>
-	      {[internal, external].map (item => (
-		  <DraggableDroppableTagRow
-		      key={item.category}
-		      tag={item}
-		      nestLevel={0}
-		      pathKey={`cat-${ item.category }-7`}
-		      suppressClickRef={{ current: false }}
-		      sp={sp}/>))}
-	    </>)
-
-	const prefix = sp ? 'tag-sp-' : 'tag-'
-	for (const item of [internal, external])
-	{
-	  expect (screen.getByRole ('link', { name: item.name })
-	      .closest ('[data-layout-id]')).toHaveAttribute (
-		  'data-layout-id', `${ prefix }${ item.category }-7`)
-	}
-      })
 })

frontend/src/components/DraggableDroppableTagRow.tsx

@@ -137,7 +137,7 @@ const DraggableDroppableTagRow: FC<Props> = ({
 		transition={{ layout: layoutTransition }}
 		layoutId={animationMode === 'off'
 		    ? undefined
-		    : `tag-${ sp ? 'sp-' : '' }${ tag.category }-${ tag.id }`}>
+		    : `tag-${ sp ? 'sp-' : '' }${ tag.id }`}>
 	      <TagLink tag={tag} nestLevel={nestLevel}/>
 	    </motion.div>)}
       </div>)

frontend/src/components/TagSidebar.test.tsx

@@ -1,47 +0,0 @@
-import { screen } from '@testing-library/react'
-import { describe, expect, it, vi } from 'vitest'
-
-import TagSidebar from '@/components/TagSidebar'
-import { buildPost, buildTag } from '@/test/factories'
-import { renderWithProviders } from '@/test/render'
-
-import type { ReactNode } from 'react'
-
-vi.mock ('@/components/TagSearch', () => ({ default: () => null }))
-vi.mock ('@/components/layout/SidebarComponent', () => ({
-    default: ({ children }: { children: ReactNode }) => <>{children}</> }))
-
-vi.mock ('framer-motion', async importOriginal => {
-  const original = await importOriginal<typeof import ('framer-motion')> ()
-  return {
-      ...original,
-      motion: {
-	  ...original.motion,
-	  div: ({ children, layoutId }: {
-	      children?: ReactNode
-	      layoutId?: string }) => (
-	      <div data-layout-id={layoutId}>{children}</div>) } }
-})
-
-describe ('TagSidebar', () => {
-  it ('keeps same-id internal and external tags with distinct identities', () => {
-    const errors = vi.spyOn (console, 'error').mockImplementation (() => {})
-    const internal = buildTag ({ id: 7, name: 'internal_collision' })
-    const external = buildTag ({
-	id: 7, name: 'nico:external_collision', category: 'nico' })
-
-    renderWithProviders (
-	<TagSidebar posts={[buildPost ({ tags: [internal, external] })]}/>)
-
-    for (const item of [internal, external])
-    {
-      const link = screen.getByRole ('link', { name: item.name })
-      expect (link).toBeInTheDocument ()
-      expect (link.closest ('[data-layout-id]')).toHaveAttribute (
-	  'data-layout-id', `tag-${ item.category }-7`)
-    }
-
-    expect (errors.mock.calls.filter (args =>
-	args.some (value => String (value).includes ('same key')))).toEqual ([])
-  })
-})

frontend/src/components/TagSidebar.tsx

@@ -84,8 +84,7 @@ const TagSidebar: FC<Props> = ({ posts, onClick }) => {
 	<ul>
 	  {CATEGORIES.flatMap (cat => cat in tags ? (
 	      tags[cat].map (tag => (
-		  <li key={`${ cat }-${ tag.id }`}
-		      className="mb-1 min-w-0 max-w-full overflow-hidden">
+		  <li key={tag.id} className="mb-1 min-w-0 max-w-full overflow-hidden">
 		    {animationsOff
 		     ? (
 			 <div className="flex min-w-0 max-w-full items-baseline overflow-hidden">
@@ -95,7 +94,7 @@ const TagSidebar: FC<Props> = ({ posts, onClick }) => {
 			 <motion.div
 			     className="flex min-w-0 max-w-full items-baseline overflow-hidden"
 			     transition={{ layout: layoutTransition }}
-			     layoutId={`tag-${ cat }-${ tag.id }`}>
+			     layoutId={`tag-${ tag.id }`}>
 			   <TagLink tag={tag} onClick={onClick}/>
 			 </motion.div>)}
 		  </li>))) : [])}

frontend/src/entry-server.tsx

@@ -1,6 +1,6 @@
 import { QueryClient, QueryClientProvider, dehydrate, skipToken } from '@tanstack/react-query'
 import { PassThrough } from 'node:stream'
-import { renderToPipeableStream } from 'react-dom/server'
+import { renderToPipeableStream, renderToStaticMarkup } from 'react-dom/server'
 import { HelmetProvider } from 'react-helmet-async'
 import { I18nextProvider } from 'react-i18next'
 import { createStaticHandler, createStaticRouter,
@@ -9,7 +9,7 @@ import { createStaticHandler, createStaticRouter,
 import { AppFrame, appRoutes, resolvePageRoute } from '@/App'
 import { apiGet, isApiError } from '@/lib/api'
 import { createUII18n } from '@/lib/i18n'
-import { fetchLocales, isLocaleCode, legacyLocalePath } from '@/lib/locales'
+import { fetchLocales, isLocaleCode, legacyLocalePath, switchLocalePath } from '@/lib/locales'
 import { localesKeys, sessionKeys } from '@/lib/queryKeys'
 import { withRenderContext } from '@/lib/renderContext.server'
 
@@ -171,8 +171,26 @@ export const render = async (
 	}))
       }
       const helmet = helmetContext.helmet!
+      const alternates = status === 200 && known != null
+	  ? await Promise.all (locales.locales.map (entry => entry.code)
+	      .filter (isLocaleCode)
+	      .filter (code => known.route.handle?.locale == null
+		  || known.route.handle.locale === code)
+	      .map (async targetLocale => {
+		const location = { pathname: url.pathname, search: url.search, hash: '' }
+		const path = targetLocale === locale
+		    ? url.pathname + url.search
+		    : (known.route.handle?.switchLocale != null
+		       ? await known.route.handle.switchLocale ({
+			   location, params: known.params, locale, targetLocale })
+		       : switchLocalePath (location, targetLocale))
+		return <link key={targetLocale} rel="alternate" hrefLang={targetLocale}
+		    href={new URL (path, origin).href}/>
+	      }))
+	  : []
       const head = [helmet.title, helmet.meta, helmet.link, helmet.style]
 	  .map (entry => entry.toString ()).join ('')
+	  + renderToStaticMarkup (<>{alternates}</>)
       const dehydrated = dehydrate (client, { shouldDehydrateQuery: query =>
 	  query.state.status !== 'pending'
 	  && query.meta?.clientOnly !== true