feat: load post cursors infinitely

src/features/posts/use-post-feed.test.ts

@@ -0,0 +1,165 @@
+import { QueryClient, QueryClientProvider } from '@tanstack/react-query'
+import { renderHook } from '@testing-library/react'
+import { createElement, type ReactNode } from 'react'
+import { beforeEach, describe, expect, it, vi } from 'vitest'
+import {
+  createPostFeedOptions,
+  PostLoadError,
+  usePostFeed,
+} from './use-post-feed'
+
+const useServerFn = vi.hoisted(() => vi.fn())
+
+vi.mock('@tanstack/react-start', async (importOriginal) => {
+  const original =
+    await importOriginal<typeof import('@tanstack/react-start')>()
+  return { ...original, useServerFn }
+})
+
+describe('createPostFeedOptions', () => {
+  it('forwards one user cursor in the server function payload', async () => {
+    const loadUser = vi.fn().mockResolvedValue({
+      ok: true,
+      page: { tweets: [], nextCursor: 'next' },
+    })
+    const options = createPostFeedOptions(
+      { kind: 'user', target: '@yuta' },
+      { loadUser, search: vi.fn() },
+    )
+
+    await options.queryFn({ pageParam: 'cursor' } as never)
+
+    expect(loadUser).toHaveBeenCalledOnce()
+    expect(loadUser).toHaveBeenCalledWith({
+      data: { target: '@yuta', cursor: 'cursor' },
+    })
+  })
+
+  it('does not retry requests automatically', () => {
+    const options = createPostFeedOptions(
+      { kind: 'user', target: 'yuta' },
+      { loadUser: vi.fn(), search: vi.fn() },
+    )
+
+    expect(options.retry).toBe(false)
+  })
+
+  it('does not refetch automatically when the window regains focus', () => {
+    const options = createPostFeedOptions(
+      { kind: 'user', target: 'yuta' },
+      { loadUser: vi.fn(), search: vi.fn() },
+    )
+
+    expect(options.refetchOnWindowFocus).toBe(false)
+  })
+
+  it('does not refetch automatically when the connection returns', () => {
+    const options = createPostFeedOptions(
+      { kind: 'user', target: 'yuta' },
+      { loadUser: vi.fn(), search: vi.fn() },
+    )
+
+    expect(options.refetchOnReconnect).toBe(false)
+  })
+
+  it('takes the next cursor only from the resolved page', () => {
+    const options = createPostFeedOptions(
+      { kind: 'user', target: 'yuta' },
+      { loadUser: vi.fn(), search: vi.fn() },
+    )
+
+    expect(
+      options.getNextPageParam({ tweets: [], nextCursor: 'page-next' }),
+    ).toBe('page-next')
+    expect(options.getNextPageParam({ tweets: [] })).toBeUndefined()
+  })
+
+  it('includes every search control in the query key', () => {
+    const options = createPostFeedOptions(
+      {
+        kind: 'search',
+        query: 'AI',
+        product: 'Top',
+        following: true,
+      },
+      { loadUser: vi.fn(), search: vi.fn() },
+    )
+
+    expect(options.queryKey).toEqual([
+      'posts',
+      { kind: 'search', query: 'AI', product: 'Top', following: true },
+    ])
+  })
+
+  it('forwards every search control with the current cursor', async () => {
+    const search = vi.fn().mockResolvedValue({
+      ok: true,
+      page: { tweets: [], nextCursor: 'search-next' },
+    })
+    const options = createPostFeedOptions(
+      {
+        kind: 'search',
+        query: 'AI lang:ja',
+        product: 'Top',
+        following: true,
+      },
+      { loadUser: vi.fn(), search },
+    )
+
+    await options.queryFn({ pageParam: 'search-cursor' } as never)
+
+    expect(search).toHaveBeenCalledOnce()
+    expect(search).toHaveBeenCalledWith({
+      data: {
+        query: 'AI lang:ja',
+        product: 'Top',
+        following: true,
+        cursor: 'search-cursor',
+      },
+    })
+  })
+
+  it('preserves a typed load failure for the feed', async () => {
+    const error = {
+      code: 'upstream' as const,
+      message: '取得できませんでした。',
+      retryable: true,
+    }
+    const options = createPostFeedOptions(
+      { kind: 'user', target: 'yuta' },
+      {
+        loadUser: vi.fn().mockResolvedValue({ ok: false, error }),
+        search: vi.fn(),
+      },
+    )
+
+    const request = options.queryFn({ pageParam: undefined } as never)
+
+    await expect(request).rejects.toBeInstanceOf(PostLoadError)
+    await expect(request).rejects.toMatchObject({
+      detail: error,
+      message: error.message,
+    })
+  })
+})
+
+describe('usePostFeed', () => {
+  beforeEach(() => {
+    useServerFn.mockReset()
+  })
+
+  it('keeps an absent request idle without calling a loader', () => {
+    const loader = vi.fn()
+    useServerFn.mockReturnValue(loader)
+    const queryClient = new QueryClient({
+      defaultOptions: { queries: { retry: false } },
+    })
+    const wrapper = ({ children }: { children: ReactNode }) =>
+      createElement(QueryClientProvider, { client: queryClient }, children)
+
+    const { result } = renderHook(() => usePostFeed(undefined), { wrapper })
+
+    expect(result.current.fetchStatus).toBe('idle')
+    expect(loader).not.toHaveBeenCalled()
+  })
+})