fix: warm parsed blocks for large notes

src/hooks/editorParsedBlockPreload.test.tsx

@@ -0,0 +1,143 @@
+import { renderHook, act } from '@testing-library/react'
+import { afterEach, beforeEach, describe, expect, it, vi } from 'vitest'
+import type { MutableRefObject } from 'react'
+import type { VaultEntry } from '../types'
+import { cacheNoteContent, clearPrefetchCache } from './useTabManagement'
+import {
+  PARSED_BLOCK_PRELOAD_DELAY_MS,
+  PARSED_BLOCK_PRELOAD_MIN_BYTES,
+  useParsedBlockPreload,
+} from './editorParsedBlockPreload'
+
+type RefSet = {
+  activeTabPathRef: MutableRefObject<string | null>
+  editorMountedRef: MutableRefObject<boolean>
+  foregroundWorkAtRef: MutableRefObject<number>
+  rawModeRef: MutableRefObject<boolean>
+}
+
+function makeEntry(overrides: Partial<VaultEntry> = {}): VaultEntry {
+  return {
+    path: '/vault/large.md',
+    filename: 'large.md',
+    title: 'Large',
+    isA: 'Note',
+    aliases: [],
+    belongsTo: [],
+    relatedTo: [],
+    status: 'Active',
+    archived: false,
+    modifiedAt: 1_700_000_000,
+    createdAt: 1_700_000_000,
+    fileSize: PARSED_BLOCK_PRELOAD_MIN_BYTES + 1,
+    snippet: '',
+    wordCount: 0,
+    relationships: {},
+    icon: null,
+    color: null,
+    order: null,
+    sidebarLabel: null,
+    template: null,
+    sort: null,
+    view: null,
+    visible: null,
+    organized: false,
+    favorite: false,
+    favoriteIndex: null,
+    listPropertiesDisplay: [],
+    outgoingLinks: [],
+    properties: {},
+    hasH1: true,
+    fileKind: 'markdown',
+    ...overrides,
+  }
+}
+
+function makeRefs(overrides: Partial<{
+  activeTabPath: string | null
+  editorMounted: boolean
+  foregroundWorkAt: number
+  rawMode: boolean
+}> = {}): RefSet {
+  return {
+    activeTabPathRef: { current: overrides.activeTabPath ?? '/vault/open.md' },
+    editorMountedRef: { current: overrides.editorMounted ?? true },
+    foregroundWorkAtRef: { current: overrides.foregroundWorkAt ?? 0 },
+    rawModeRef: { current: overrides.rawMode ?? false },
+  }
+}
+
+function renderParsedPreload(refs: RefSet, prepareParsedBlocks: (event: {
+  entry: VaultEntry | null
+  path: string
+  content: string
+}) => Promise<void>) {
+  return renderHook(() => useParsedBlockPreload({
+    ...refs,
+    prepareParsedBlocks,
+  }))
+}
+
+async function emitResolvedContent(entry: VaultEntry, content = '# Large\n\nBody'): Promise<void> {
+  await act(async () => {
+    cacheNoteContent(entry.path, content, entry)
+    await vi.advanceTimersByTimeAsync(PARSED_BLOCK_PRELOAD_DELAY_MS)
+  })
+}
+
+describe('useParsedBlockPreload', () => {
+  beforeEach(() => {
+    vi.useFakeTimers()
+    vi.setSystemTime(new Date('2026-05-14T12:00:00Z'))
+    clearPrefetchCache()
+  })
+
+  afterEach(() => {
+    clearPrefetchCache()
+    vi.useRealTimers()
+    vi.restoreAllMocks()
+  })
+
+  it('prepares parsed blocks for a warmed large markdown note after foreground work is idle', async () => {
+    const refs = makeRefs()
+    const prepareParsedBlocks = vi.fn(async () => {})
+    const entry = makeEntry()
+
+    renderParsedPreload(refs, prepareParsedBlocks)
+    await emitResolvedContent(entry, '# Large\n\nPrepared body.')
+
+    expect(prepareParsedBlocks).toHaveBeenCalledWith({
+      entry,
+      path: entry.path,
+      content: '# Large\n\nPrepared body.',
+    })
+  })
+
+  it('skips entries that should not compete with the foreground editor', async () => {
+    const activeEntry = makeEntry({ path: '/vault/active.md' })
+    const refs = makeRefs({ activeTabPath: activeEntry.path })
+    const prepareParsedBlocks = vi.fn(async () => {})
+    renderParsedPreload(refs, prepareParsedBlocks)
+
+    await emitResolvedContent(activeEntry)
+    await emitResolvedContent(makeEntry({ path: '/vault/small.md', fileSize: PARSED_BLOCK_PRELOAD_MIN_BYTES - 1 }))
+    await emitResolvedContent(makeEntry({ path: '/vault/file.bin', fileKind: 'binary' }))
+
+    expect(prepareParsedBlocks).not.toHaveBeenCalled()
+  })
+
+  it('drops a candidate that becomes active before the idle preparse starts', async () => {
+    const entry = makeEntry({ path: '/vault/soon-active.md' })
+    const refs = makeRefs()
+    const prepareParsedBlocks = vi.fn(async () => {})
+
+    renderParsedPreload(refs, prepareParsedBlocks)
+    cacheNoteContent(entry.path, '# Soon Active\n\nBody', entry)
+    refs.activeTabPathRef.current = entry.path
+    await act(async () => {
+      await vi.advanceTimersByTimeAsync(PARSED_BLOCK_PRELOAD_DELAY_MS)
+    })
+
+    expect(prepareParsedBlocks).not.toHaveBeenCalled()
+  })
+})

src/hooks/editorParsedBlockPreload.ts

@@ -5,7 +5,7 @@ import { subscribeNoteContentResolved } from './noteContentCache'
 export const PARSED_BLOCK_PRELOAD_MIN_BYTES = 32 * 1024
 export const PARSED_BLOCK_PRELOAD_DELAY_MS = 1800
 export const PARSED_BLOCK_PRELOAD_FOREGROUND_IDLE_MS = 1500
-export const PARSED_BLOCK_PRELOAD_ENABLED = false
+export const PARSED_BLOCK_PRELOAD_ENABLED = true
 
 type PrepareParsedBlocks = (event: NoteContentResolvedEvent) => Promise<void>
 

src/hooks/editorTabContent.test.ts

@@ -1,5 +1,215 @@
 import { describe, expect, it } from 'vitest'
-import { slugifyPathStem } from './editorTabContent'
+import {
+  extractEditorBody,
+  getH1TextFromBlocks,
+  normalizeParsedImageBlocks,
+  replaceTitleInFrontmatter,
+  slugifyPathStem,
+} from './editorTabContent'
+
+function makeHeadingBlocks(
+  content: Array<Record<string, unknown>>,
+  level = 1,
+) {
+  return [{
+    type: 'heading',
+    props: { level },
+    content,
+  }]
+}
+
+describe('extractEditorBody', () => {
+  it('strips frontmatter and preserves H1 heading for new note content', () => {
+    const content = '---\ntitle: Untitled note\ntype: Note\nstatus: Active\n---\n\n# Untitled note\n\n'
+    expect(extractEditorBody(content)).toBe('# Untitled note\n\n')
+  })
+
+  it('strips frontmatter and preserves H1 with body content', () => {
+    const content = '---\ntitle: Test\n---\n# Test\n\nBody text here.'
+    expect(extractEditorBody(content)).toBe('# Test\n\nBody text here.')
+  })
+
+  it('preserves H1 and body content after frontmatter', () => {
+    const content = '---\ntitle: My Note\ntype: Note\n---\n\n# My Note\n\nFirst paragraph.\n\nSecond paragraph.'
+    expect(extractEditorBody(content)).toBe('# My Note\n\nFirst paragraph.\n\nSecond paragraph.')
+  })
+
+  it('handles content without frontmatter', () => {
+    const content = '# Just a Heading\n\nSome body text.'
+    expect(extractEditorBody(content)).toBe('# Just a Heading\n\nSome body text.')
+  })
+
+  it('handles content without frontmatter or heading', () => {
+    const content = 'Just plain text.'
+    expect(extractEditorBody(content)).toBe('Just plain text.')
+  })
+
+  it('handles completely empty content', () => {
+    expect(extractEditorBody('')).toBe('')
+  })
+
+  it('handles frontmatter-only content', () => {
+    const content = '---\ntitle: Empty\n---\n'
+    expect(extractEditorBody(content)).toBe('')
+  })
+
+  it('preserves wikilinks in body', () => {
+    const content = '---\ntitle: Test\n---\n\n# Test\n\nSee [[Other Note]] for details.'
+    expect(extractEditorBody(content)).toBe('# Test\n\nSee [[Other Note]] for details.')
+  })
+
+  it('preserves non-leading headings', () => {
+    const content = '---\ntitle: Test\n---\n\nSome intro text.\n\n# A Heading\n\nMore text.'
+    expect(extractEditorBody(content)).toBe('Some intro text.\n\n# A Heading\n\nMore text.')
+  })
+
+  it('preserves H1 for buildNoteContent output', () => {
+    const content = '---\ntitle: My Project\ntype: Project\nstatus: Active\n---\n\n# My Project\n\n'
+    expect(extractEditorBody(content)).toBe('# My Project\n\n')
+  })
+
+  it('preserves an empty H1 for untitled-note content', () => {
+    const content = '---\ntype: Note\nstatus: Active\n---\n\n# \n\n'
+    expect(extractEditorBody(content)).toBe('# \n\n')
+  })
+})
+
+describe('getH1TextFromBlocks', () => {
+  it('returns text from H1 heading block', () => {
+    const blocks = makeHeadingBlocks([{ type: 'text', text: 'My Title', styles: {} }])
+    expect(getH1TextFromBlocks(blocks)).toBe('My Title')
+  })
+
+  it('returns null for empty blocks', () => {
+    expect(getH1TextFromBlocks([])).toBeNull()
+  })
+
+  it('returns null for non-heading first block', () => {
+    const blocks = [{
+      type: 'paragraph',
+      content: [{ type: 'text', text: 'Just text' }],
+    }]
+    expect(getH1TextFromBlocks(blocks)).toBeNull()
+  })
+
+  it('returns null for H2 heading', () => {
+    const blocks = makeHeadingBlocks([{ type: 'text', text: 'Subtitle' }], 2)
+    expect(getH1TextFromBlocks(blocks)).toBeNull()
+  })
+
+  it('concatenates multiple text spans', () => {
+    const blocks = makeHeadingBlocks([
+      { type: 'text', text: 'Hello ' },
+      { type: 'text', text: 'World' },
+    ])
+    expect(getH1TextFromBlocks(blocks)).toBe('Hello World')
+  })
+
+  it('returns null for empty H1 content', () => {
+    const blocks = makeHeadingBlocks([])
+    expect(getH1TextFromBlocks(blocks)).toBeNull()
+  })
+
+  it('returns null for whitespace-only H1', () => {
+    const blocks = makeHeadingBlocks([{ type: 'text', text: '   ' }])
+    expect(getH1TextFromBlocks(blocks)).toBeNull()
+  })
+
+  it('returns null when blocks is null/undefined', () => {
+    expect(getH1TextFromBlocks(null as unknown as unknown[])).toBeNull()
+    expect(getH1TextFromBlocks(undefined as unknown as unknown[])).toBeNull()
+  })
+
+  it('filters non-text inline content', () => {
+    const blocks = makeHeadingBlocks([
+      { type: 'text', text: 'Title' },
+      { type: 'wikilink', props: { target: 'linked' } },
+    ])
+    expect(getH1TextFromBlocks(blocks)).toBe('Title')
+  })
+})
+
+describe('replaceTitleInFrontmatter', () => {
+  it('replaces title value in frontmatter', () => {
+    const fm = '---\ntitle: Old Title\ntype: Note\n---\n\n'
+    expect(replaceTitleInFrontmatter(fm, 'New Title')).toBe('---\ntitle: New Title\ntype: Note\n---\n\n')
+  })
+
+  it('handles title with extra spaces after colon', () => {
+    const fm = '---\ntitle:   Old Title\n---\n'
+    expect(replaceTitleInFrontmatter(fm, 'New Title')).toBe('---\ntitle:   New Title\n---\n')
+  })
+
+  it('returns unchanged frontmatter when no title line exists', () => {
+    const fm = '---\ntype: Note\n---\n'
+    expect(replaceTitleInFrontmatter(fm, 'New Title')).toBe('---\ntype: Note\n---\n')
+  })
+
+  it('replaces only the title line, not other fields', () => {
+    const fm = '---\ntitle: Old\ntype: Note\nstatus: Active\n---\n\n'
+    expect(replaceTitleInFrontmatter(fm, 'Updated')).toBe('---\ntitle: Updated\ntype: Note\nstatus: Active\n---\n\n')
+  })
+
+  it('handles empty string as frontmatter', () => {
+    expect(replaceTitleInFrontmatter('', 'Title')).toBe('')
+  })
+})
+
+describe('normalizeParsedImageBlocks', () => {
+  it('clears broken-image fallback widths from local asset image blocks', () => {
+    const blocks = normalizeParsedImageBlocks([{
+      type: 'image',
+      props: {
+        url: 'asset://localhost/%2Fvault%2Fattachments%2Fshot.png',
+        previewWidth: 16,
+      },
+    }])
+
+    expect(blocks).toEqual([{
+      type: 'image',
+      props: {
+        url: 'asset://localhost/%2Fvault%2Fattachments%2Fshot.png',
+        previewWidth: undefined,
+      },
+    }])
+  })
+
+  it('preserves explicit image widths and non-local image URLs', () => {
+    const blocks = normalizeParsedImageBlocks([
+      {
+        type: 'image',
+        props: {
+          url: 'asset://localhost/%2Fvault%2Fattachments%2Fresized.png',
+          previewWidth: 240,
+        },
+      },
+      {
+        type: 'image',
+        props: {
+          url: 'https://example.test/preview.png',
+          previewWidth: 16,
+        },
+      },
+    ])
+
+    expect(blocks).toEqual([
+      {
+        type: 'image',
+        props: {
+          url: 'asset://localhost/%2Fvault%2Fattachments%2Fresized.png',
+          previewWidth: 240,
+        },
+      },
+      {
+        type: 'image',
+        props: {
+          url: 'https://example.test/preview.png',
+          previewWidth: 16,
+        },
+      },
+    ])
+  })
+})
 
 describe('slugifyPathStem', () => {
   it('preserves Unicode title stems for untitled rename detection', () => {

src/hooks/useEditorTabSwap.test.ts

@@ -1,203 +1,8 @@
 import { describe, it, expect, vi, afterEach } from 'vitest'
 import { renderHook, act } from '@testing-library/react'
-import { extractEditorBody, getH1TextFromBlocks, replaceTitleInFrontmatter, RICH_EDITOR_CHANGE_DEBOUNCE_MS, useEditorTabSwap } from './useEditorTabSwap'
-import { normalizeParsedImageBlocks } from './editorTabContent'
-import { cacheNoteContent, clearPrefetchCache } from './useTabManagement'
+import { RICH_EDITOR_CHANGE_DEBOUNCE_MS, useEditorTabSwap } from './useEditorTabSwap'
 import { cacheParsedNoteBlocks, clearParsedNoteBlockCache } from './editorParsedBlockCache'
 
-describe('extractEditorBody', () => {
-  it('strips frontmatter and preserves H1 heading for new note content', () => {
-    const content = '---\ntitle: Untitled note\ntype: Note\nstatus: Active\n---\n\n# Untitled note\n\n'
-    expect(extractEditorBody(content)).toBe('# Untitled note\n\n')
-  })
-
-  it('strips frontmatter and preserves H1 with body content', () => {
-    const content = '---\ntitle: Test\n---\n# Test\n\nBody text here.'
-    expect(extractEditorBody(content)).toBe('# Test\n\nBody text here.')
-  })
-
-  it('preserves H1 and body content after frontmatter', () => {
-    const content = '---\ntitle: My Note\ntype: Note\n---\n\n# My Note\n\nFirst paragraph.\n\nSecond paragraph.'
-    expect(extractEditorBody(content)).toBe('# My Note\n\nFirst paragraph.\n\nSecond paragraph.')
-  })
-
-  it('handles content without frontmatter', () => {
-    const content = '# Just a Heading\n\nSome body text.'
-    expect(extractEditorBody(content)).toBe('# Just a Heading\n\nSome body text.')
-  })
-
-  it('handles content without frontmatter or heading', () => {
-    const content = 'Just plain text.'
-    expect(extractEditorBody(content)).toBe('Just plain text.')
-  })
-
-  it('handles completely empty content', () => {
-    expect(extractEditorBody('')).toBe('')
-  })
-
-  it('handles frontmatter-only content', () => {
-    const content = '---\ntitle: Empty\n---\n'
-    expect(extractEditorBody(content)).toBe('')
-  })
-
-  it('preserves wikilinks in body', () => {
-    const content = '---\ntitle: Test\n---\n\n# Test\n\nSee [[Other Note]] for details.'
-    expect(extractEditorBody(content)).toBe('# Test\n\nSee [[Other Note]] for details.')
-  })
-
-  it('preserves non-leading headings', () => {
-    const content = '---\ntitle: Test\n---\n\nSome intro text.\n\n# A Heading\n\nMore text.'
-    expect(extractEditorBody(content)).toBe('Some intro text.\n\n# A Heading\n\nMore text.')
-  })
-
-  it('preserves H1 for buildNoteContent output', () => {
-    const content = '---\ntitle: My Project\ntype: Project\nstatus: Active\n---\n\n# My Project\n\n'
-    expect(extractEditorBody(content)).toBe('# My Project\n\n')
-  })
-
-  it('preserves an empty H1 for untitled-note content', () => {
-    const content = '---\ntype: Note\nstatus: Active\n---\n\n# \n\n'
-    expect(extractEditorBody(content)).toBe('# \n\n')
-  })
-})
-
-describe('getH1TextFromBlocks', () => {
-  it('returns text from H1 heading block', () => {
-    const blocks = makeHeadingBlocks([{ type: 'text', text: 'My Title', styles: {} }])
-    expect(getH1TextFromBlocks(blocks)).toBe('My Title')
-  })
-
-  it('returns null for empty blocks', () => {
-    expect(getH1TextFromBlocks([])).toBeNull()
-  })
-
-  it('returns null for non-heading first block', () => {
-    const blocks = [{
-      type: 'paragraph',
-      content: [{ type: 'text', text: 'Just text' }],
-    }]
-    expect(getH1TextFromBlocks(blocks)).toBeNull()
-  })
-
-  it('returns null for H2 heading', () => {
-    const blocks = makeHeadingBlocks([{ type: 'text', text: 'Subtitle' }], 2)
-    expect(getH1TextFromBlocks(blocks)).toBeNull()
-  })
-
-  it('concatenates multiple text spans', () => {
-    const blocks = makeHeadingBlocks([
-      { type: 'text', text: 'Hello ' },
-      { type: 'text', text: 'World' },
-    ])
-    expect(getH1TextFromBlocks(blocks)).toBe('Hello World')
-  })
-
-  it('returns null for empty H1 content', () => {
-    const blocks = makeHeadingBlocks([])
-    expect(getH1TextFromBlocks(blocks)).toBeNull()
-  })
-
-  it('returns null for whitespace-only H1', () => {
-    const blocks = makeHeadingBlocks([{ type: 'text', text: '   ' }])
-    expect(getH1TextFromBlocks(blocks)).toBeNull()
-  })
-
-  it('returns null when blocks is null/undefined', () => {
-    expect(getH1TextFromBlocks(null as unknown as unknown[])).toBeNull()
-    expect(getH1TextFromBlocks(undefined as unknown as unknown[])).toBeNull()
-  })
-
-  it('filters non-text inline content', () => {
-    const blocks = makeHeadingBlocks([
-      { type: 'text', text: 'Title' },
-      { type: 'wikilink', props: { target: 'linked' } },
-    ])
-    expect(getH1TextFromBlocks(blocks)).toBe('Title')
-  })
-})
-
-describe('replaceTitleInFrontmatter', () => {
-  it('replaces title value in frontmatter', () => {
-    const fm = '---\ntitle: Old Title\ntype: Note\n---\n\n'
-    expect(replaceTitleInFrontmatter(fm, 'New Title')).toBe('---\ntitle: New Title\ntype: Note\n---\n\n')
-  })
-
-  it('handles title with extra spaces after colon', () => {
-    const fm = '---\ntitle:   Old Title\n---\n'
-    expect(replaceTitleInFrontmatter(fm, 'New Title')).toBe('---\ntitle:   New Title\n---\n')
-  })
-
-  it('returns unchanged frontmatter when no title line exists', () => {
-    const fm = '---\ntype: Note\n---\n'
-    expect(replaceTitleInFrontmatter(fm, 'New Title')).toBe('---\ntype: Note\n---\n')
-  })
-
-  it('replaces only the title line, not other fields', () => {
-    const fm = '---\ntitle: Old\ntype: Note\nstatus: Active\n---\n\n'
-    expect(replaceTitleInFrontmatter(fm, 'Updated')).toBe('---\ntitle: Updated\ntype: Note\nstatus: Active\n---\n\n')
-  })
-
-  it('handles empty string as frontmatter', () => {
-    expect(replaceTitleInFrontmatter('', 'Title')).toBe('')
-  })
-})
-
-describe('normalizeParsedImageBlocks', () => {
-  it('clears broken-image fallback widths from local asset image blocks', () => {
-    const blocks = normalizeParsedImageBlocks([{
-      type: 'image',
-      props: {
-        url: 'asset://localhost/%2Fvault%2Fattachments%2Fshot.png',
-        previewWidth: 16,
-      },
-    }])
-
-    expect(blocks).toEqual([{
-      type: 'image',
-      props: {
-        url: 'asset://localhost/%2Fvault%2Fattachments%2Fshot.png',
-        previewWidth: undefined,
-      },
-    }])
-  })
-
-  it('preserves explicit image widths and non-local image URLs', () => {
-    const blocks = normalizeParsedImageBlocks([
-      {
-        type: 'image',
-        props: {
-          url: 'asset://localhost/%2Fvault%2Fattachments%2Fresized.png',
-          previewWidth: 240,
-        },
-      },
-      {
-        type: 'image',
-        props: {
-          url: 'https://example.test/preview.png',
-          previewWidth: 16,
-        },
-      },
-    ])
-
-    expect(blocks).toEqual([
-      {
-        type: 'image',
-        props: {
-          url: 'asset://localhost/%2Fvault%2Fattachments%2Fresized.png',
-          previewWidth: 240,
-        },
-      },
-      {
-        type: 'image',
-        props: {
-          url: 'https://example.test/preview.png',
-          previewWidth: 16,
-        },
-      },
-    ])
-  })
-})
-
 const blocksA = [{ type: 'paragraph', content: [{ type: 'text', text: 'A' }] }]
 
 function makeTextParagraphBlock(text: string) {
@@ -248,17 +53,6 @@ function makeMockEditor(docRef: { current: unknown[] }) {
   return editor
 }
 
-function makeHeadingBlocks(
-  content: Array<Record<string, unknown>>,
-  level = 1,
-) {
-  return [{
-    type: 'heading',
-    props: { level },
-    content,
-  }]
-}
-
 function makeLongNoteBlocks(wordCount: number) {
   const words = Array.from({ length: wordCount }, (_, index) => `word${index}`)
   const paragraphs: unknown[] = []
@@ -512,32 +306,6 @@ describe('useEditorTabSwap raw mode sync', () => {
     ])
   })
 
-  it('does not preparse prefetched note blocks in the background', async () => {
-    clearPrefetchCache()
-    const tabA = makeTab('a.md', 'Note A')
-    const tabB = {
-      ...makeTab('b.md', 'Likely Next'),
-      content: '---\ntitle: Likely Next\n---\n\n# Likely Next\n\nPrepared body.',
-    }
-
-    const { mockEditor, rerenderWith } = await createSwapHarness({
-      initialProps: { tabs: [tabA], activeTabPath: 'a.md', rawMode: false },
-    })
-    mockEditor.tryParseMarkdownToBlocks.mockClear()
-
-    cacheNoteContent('b.md', tabB.content)
-    await flushEditorTick()
-
-    expect(mockEditor.tryParseMarkdownToBlocks).not.toHaveBeenCalled()
-
-    await rerenderWith({ tabs: [tabB], activeTabPath: 'b.md' })
-
-    expect(mockEditor.tryParseMarkdownToBlocks).toHaveBeenCalledWith(
-      expect.stringContaining('Prepared body.'),
-    )
-    clearPrefetchCache()
-  })
-
   it('clears stale editor DOM selection before switching notes', async () => {
     const tabA = makeTab('a.md', 'Note A')
     const tabB = makeTab('b.md', 'Note B')