frontend/src/components/layout/SidebarComponent.test.tsx

@@ -0,0 +1,99 @@
+import { fireEvent, render, screen, waitFor } from '@testing-library/react'
+import { HelmetProvider } from 'react-helmet-async'
+import { beforeEach, describe, expect, it, vi } from 'vitest'
+
+import SidebarComponent from '@/components/layout/SidebarComponent'
+
+
+const sidebarWidth = (element: Element | null): string =>
+    (element as HTMLElement).style.getPropertyValue ('--sidebar-width')
+
+
+const sidebarRoot = (container: HTMLElement): Element =>
+    container.querySelector ('[style*="--sidebar-width"]')!
+
+
+const renderSidebar = (
+    props: Partial<Parameters<typeof SidebarComponent>[0]> = {},
+    containerWidth = 800,
+) => {
+  Object.defineProperty (HTMLElement.prototype, 'clientWidth', {
+      configurable: true,
+      get () {
+	return this.hasAttribute ('data-sidebar-container') ? containerWidth : 0
+      },
+  })
+
+  const rendered = render (
+      <HelmetProvider>
+	<div data-sidebar-container>
+	  <SidebarComponent sidebarKey="test-sidebar" {...props}>
+	    Sidebar body
+	  </SidebarComponent>
+	</div>
+      </HelmetProvider>)
+
+  return rendered
+}
+
+
+describe ('SidebarComponent', () => {
+  beforeEach (() => {
+    Object.defineProperty (window, 'innerWidth', {
+	configurable: true,
+	value:        1_000,
+    })
+
+    Object.defineProperty (HTMLElement.prototype, 'setPointerCapture', {
+	configurable: true,
+	value:        vi.fn (),
+    })
+    Object.defineProperty (HTMLElement.prototype, 'releasePointerCapture', {
+	configurable: true,
+	value:        vi.fn (),
+    })
+    Object.defineProperty (HTMLElement.prototype, 'hasPointerCapture', {
+	configurable: true,
+	value:        vi.fn (() => true),
+    })
+
+    vi.spyOn (HTMLElement.prototype, 'setPointerCapture').mockImplementation (() => {
+      ;
+    })
+    vi.spyOn (HTMLElement.prototype, 'releasePointerCapture').mockImplementation (() => {
+      ;
+    })
+    vi.spyOn (HTMLElement.prototype, 'hasPointerCapture').mockReturnValue (true)
+  })
+
+  it ('uses maxWidth without applying the container main-width reserve twice', async () => {
+    localStorage.setItem ('sidebar:test-sidebar:left:width', '700')
+    const onWidthChange = vi.fn ()
+
+    const { container } = renderSidebar ({ maxWidth: 700, onWidthChange }, 800)
+
+    await waitFor (() => {
+      expect (sidebarWidth (sidebarRoot (container))).toBe ('700px')
+    })
+    expect (onWidthChange).toHaveBeenLastCalledWith (700)
+  })
+
+  it ('resets width and removes only its storage key on double click', async () => {
+    localStorage.setItem ('sidebar:test-sidebar:right:width', '420')
+    localStorage.setItem ('sidebar:other-sidebar:right:width', '480')
+
+    const { container } = renderSidebar ({ side: 'right' }, 900)
+
+    await waitFor (() => {
+      expect (sidebarWidth (sidebarRoot (container))).toBe ('420px')
+    })
+
+    fireEvent.doubleClick (screen.getByRole ('separator', { name: 'サイドバー幅' }))
+
+    await waitFor (() => {
+      expect (sidebarWidth (sidebarRoot (container))).toBe ('256px')
+    })
+    expect (localStorage.getItem ('sidebar:test-sidebar:right:width')).toBeNull ()
+    expect (localStorage.getItem ('sidebar:other-sidebar:right:width')).toBe ('480')
+  })
+})

frontend/src/components/layout/SidebarComponent.tsx

@@ -47,23 +47,16 @@ const getSidebarMaxWidth = (containerWidth: number): number => {
 }
 
 
-const clampSidebarWidth = (width: number, containerWidth: number): number =>
-    Math.min (getSidebarMaxWidth (containerWidth), Math.max (MIN_SIDEBAR_WIDTH, width))
-
-
 const readStoredSidebarWidth = (
     sidebarKey: string,
-    side: SidebarSide,
-    containerWidth: number): number => {
+    side: SidebarSide): number => {
   if (typeof window === 'undefined')
     return DEFAULT_SIDEBAR_WIDTH
 
   const value = window.localStorage.getItem (storageKeyForSidebar (sidebarKey, side))
   const width = value == null ? Number.NaN : Number (value)
 
-  return Number.isFinite (width)
-	 ? clampSidebarWidth (width, containerWidth)
-	 : clampSidebarWidth (DEFAULT_SIDEBAR_WIDTH, containerWidth)
+  return Number.isFinite (width) ? width : DEFAULT_SIDEBAR_WIDTH
 }
 
 
@@ -101,7 +94,7 @@ const SidebarComponent: FC<Props> = ({
       typeof window === 'undefined'
       ? DEFAULT_SIDEBAR_WIDTH
       : getClampedWidth (
-	  readStoredSidebarWidth (sidebarKey, side, window.innerWidth),
+	  readStoredSidebarWidth (sidebarKey, side),
 	  window.innerWidth)))
   const [resizing, setResizing] = useState (false)
   const widthRef = useRef (width)
@@ -256,7 +249,7 @@ const SidebarComponent: FC<Props> = ({
   useEffect (() => {
     const containerWidth = getContainerWidth ()
     const nextWidth = getClampedWidth (
-	readStoredSidebarWidth (sidebarKey, side, containerWidth),
+	readStoredSidebarWidth (sidebarKey, side),
 	containerWidth)
     widthRef.current = nextWidth
     setWidth (nextWidth)

frontend/src/pages/theatres/TheatreDetailPage.test.tsx

@@ -105,6 +105,20 @@ const tagSection = (): HTMLElement =>
   screen.getAllByRole ('heading', { name: 'タグ' })[0].closest ('section')!
 
 const mockDefaultApi = () => {
+  let commentsFetched = false
+  let currentTheatreInfo = buildTheatreInfo ({
+    postId:        currentPost.id,
+    postStartedAt: '2026-01-02T03:04:05.000Z',
+    postElapsedMs: 1_000,
+    watchingUsers,
+    skipVote:      {
+      votesCount:         0,
+      requiredCount:      2,
+      watchingUsersCount: watchingUsers.length,
+      voted:              false,
+    },
+  })
+
   api.apiGet.mockImplementation ((path: string) => {
     switch (path)
     {
@@ -112,13 +126,17 @@ const mockDefaultApi = () => {
       return Promise.resolve (theatre)
 
     case '/theatres/7/comments':
+      if (commentsFetched)
+	return Promise.resolve ([])
+
+      commentsFetched = true
       return Promise.resolve ([
-        buildTheatreComment ({
-          theatreId: 7,
-          no:        2,
-          user:      { id: 1, name: 'tester' },
-          content:   '視聴コメント',
-        }),
+	  buildTheatreComment ({
+	    theatreId: 7,
+	    no:        2,
+	    user:      { id: 1, name: 'tester' },
+	    content:   '視聴コメント',
+	  }),
       ])
 
     case '/theatres/7/programmes':
@@ -136,32 +154,22 @@ const mockDefaultApi = () => {
     switch (path)
     {
     case '/theatres/7/watching':
-      return Promise.resolve (buildTheatreInfo ({
-        postId:        currentPost.id,
-        postStartedAt: '2026-01-02T03:04:05.000Z',
-        postElapsedMs: 1_000,
-        watchingUsers,
-        skipVote:      {
-          votesCount:         0,
-          requiredCount:      2,
-          watchingUsersCount: watchingUsers.length,
-          voted:              false,
-        },
-      }))
+      return Promise.resolve (currentTheatreInfo)
 
     case '/theatres/7/skip_vote':
-      return Promise.resolve (buildTheatreInfo ({
-        postId:        currentPost.id,
-        postStartedAt: '2026-01-02T03:04:05.000Z',
-        postElapsedMs: 2_000,
-        watchingUsers,
-        skipVote:      {
-          votesCount:         1,
-          requiredCount:      2,
-          watchingUsersCount: watchingUsers.length,
-          voted:              true,
-        },
-      }))
+      currentTheatreInfo = buildTheatreInfo ({
+	postId:        currentPost.id,
+	postStartedAt: '2026-01-02T03:04:05.000Z',
+	postElapsedMs: 2_000,
+	watchingUsers,
+	skipVote:      {
+	  votesCount:         1,
+	  requiredCount:      2,
+	  watchingUsersCount: watchingUsers.length,
+	  voted:              true,
+	},
+      })
+      return Promise.resolve (currentTheatreInfo)
 
     default:
       return Promise.reject (new Error (`Unexpected PUT ${ path }`))

frontend/src/pages/theatres/TheatreDetailPage.tsx

@@ -266,6 +266,7 @@ const TheatreDetailPage: FC<Props> = ({ user }: Props) => {
 
   const applyTheatreInfo = useCallback ((nextInfo: TheatreInfo) => {
     theatreInfoReceivedAtRef.current = performance.now ()
+    theatreInfoRef.current = nextInfo
     setTheatreInfo (nextInfo)
   }, [])
 
@@ -406,6 +407,9 @@ const TheatreDetailPage: FC<Props> = ({ user }: Props) => {
 	    setComments (prev => [...newComments, ...prev])
 	  }
 
+	if (loadingRef.current)
+	  return
+
 	const currentInfo = theatreInfoRef.current
 	const ended =
 	    currentInfo.hostFlg
@@ -427,8 +431,9 @@ const TheatreDetailPage: FC<Props> = ({ user }: Props) => {
 	    return
 	  }
 
+	const watchingRequestedAt = performance.now ()
 	const nextInfo = await apiPut<TheatreInfo> (`/theatres/${ id }/watching`)
-	if (!(cancelled))
+	if (!(cancelled) && watchingRequestedAt >= theatreInfoReceivedAtRef.current)
 	  applyTheatreInfo (nextInfo)
       }
       catch (error)
@@ -557,6 +562,7 @@ const TheatreDetailPage: FC<Props> = ({ user }: Props) => {
     if (!(id) || !(post))
       return
 
+    loadingRef.current = true
     setLoading (true)
     try
     {
@@ -585,6 +591,7 @@ const TheatreDetailPage: FC<Props> = ({ user }: Props) => {
     }
     finally
     {
+      loadingRef.current = false
       setLoading (false)
     }
   }