packages/desktop/test/unit/specs/toc-keys.spec.ts - develop - githubmirror/marktext

packages/desktop/test/unit/specs/toc-keys.spec.ts

58 строк2 KB

Ran Luo

fix(desktop): keep TOC collapse state when switching between files (#3791) (#4860)

05 июл 2026, 08:09

05 июл 2026, 08:09e367777

import { describe, it, expect } from 'vitest'
import { deriveKeyedToc } from '@/util/tocKeys'

// #3791: the TOC's collapse state is remembered by these keys. They must be
// derived from the content-based `githubSlug` so they survive a tab switch
// (which rebuilds every heading block with a fresh object-identity `slug`),
// not only same-tab edits (#3028).

const flatKeys = (nodes: ReturnType<typeof deriveKeyedToc>): string[] =>
  nodes.flatMap((n) => [n.key, ...flatKeys(n.children)])

describe('deriveKeyedToc', () => {
  it('keys nodes by githubSlug, deduplicated in document order', () => {
    const keyed = deriveKeyedToc([
      { label: 'Intro', slug: 'uid-1', githubSlug: 'intro', children: [] },
      { label: 'Intro', slug: 'uid-2', githubSlug: 'intro', children: [] }
    ])
    expect(keyed.map((n) => n.key)).toEqual(['intro', 'intro-1'])
  })

  it('produces identical keys when the same document is rebuilt with fresh slugs (tab switch)', () => {
    // Same headings/content, different per-render object-identity slugs — this
    // is exactly what Editor.setContent does when you switch back to a tab.
    const doc = (p: string) => [
      {
        label: 'A',
        slug: `${p}-1`,
        githubSlug: 'a',
        children: [{ label: 'B', slug: `${p}-2`, githubSlug: 'b', children: [] }]
      },
      { label: 'C', slug: `${p}-3`, githubSlug: 'c', children: [] }
    ]

    const before = deriveKeyedToc(doc('old'))
    const after = deriveKeyedToc(doc('new'))

    // Keys are stable across the rebuild, so collapse state keyed by them
    // survives the switch (they would differ if keyed by `slug`).
    expect(flatKeys(after)).toEqual(flatKeys(before))
    expect(flatKeys(after)).toEqual(['a', 'b', 'c'])
  })

  it('falls back to a stable placeholder for unsluggable headings', () => {
    const keyed = deriveKeyedToc([
      { label: '🎉', slug: 'uid-1', githubSlug: '', children: [] },
      { label: '🎊', slug: 'uid-2', githubSlug: '', children: [] }
    ])
    expect(keyed.map((n) => n.key)).toEqual(['heading', 'heading-1'])
  })

  it('preserves slug (for the scroll-to-heading payload) while keying by githubSlug', () => {
    const keyed = deriveKeyedToc([
      { label: 'A', slug: 'uid-42', githubSlug: 'a', children: [] }
    ])
    expect(keyed[0].slug).toBe('uid-42')
    expect(keyed[0].key).toBe('a')
  })
})