Tab opening ranking (#23435)

* Add literal-basename file matching for tab opening

- Distinguish literal filename matches from fuzzy matches
- Prioritize search for short tokens (1-2 Latin characters)
- Sort literal matches naturally instead of by fuzzy score
- Reserve search option even when literal matches fill results

* Keep literal-basename file matches in tab entry options

Ensure literal-basename file matches appear in tab creation suggestions
as fallback options when exact-basename matches exist, improving file
discovery for users.

src/renderer/src/components/tab-bar/TabBarCreateEntry.search.test.tsx

@@ -99,6 +99,66 @@ afterEach(() => {
 })
 
 describe('TabBarCreateEntry search behavior', () => {
+  it.each([false, true])('searches weak file matches on Enter (delayed listing: %s)', (delayed) => {
+    const readyListing = {
+      files: [
+        'tests/e2e/terminal-split-activation-latency-main-probe.ts',
+        'src/main/linear/issue-context-inline-media.test.ts',
+        'src/renderer/src/components/editor/combined-diff/resolve-changes/combined-diff-section-cache-match.ts'
+      ],
+      loading: false,
+      loadError: null
+    }
+    fileListMock.current = delayed ? { files: [], loading: true, loadError: null } : readyListing
+    const onOpenEntry = vi.fn().mockResolvedValue(undefined)
+    renderEntry({ onOpenEntry })
+    setQuery('asciinema')
+
+    if (delayed) {
+      expect(container.querySelector('[aria-selected="true"]')).toBeNull()
+      submit()
+      expect(onOpenEntry).not.toHaveBeenCalled()
+      fileListMock.current = readyListing
+      renderEntry({ onOpenEntry })
+    }
+
+    expect(container.querySelector('[role="option"]')?.textContent).toContain('Search Google')
+    expect(container.querySelector('[aria-selected="true"]')?.textContent).toContain(
+      'Search Google'
+    )
+    submit()
+    expect(onOpenEntry).toHaveBeenCalledWith(
+      expect.objectContaining({
+        classification: { kind: 'search', engine: 'google', query: 'asciinema' }
+      })
+    )
+  })
+
+  it.each(['a', 'ab', 'asciinema'])('waits for an exact filename before arming %s', (query) => {
+    fileListMock.current = { files: [], loading: true, loadError: null }
+    const onOpenEntry = vi.fn().mockResolvedValue(undefined)
+    renderEntry({ onOpenEntry })
+    setQuery(query)
+
+    expect(container.querySelector('[aria-selected="true"]')).toBeNull()
+    submit()
+    expect(onOpenEntry).not.toHaveBeenCalled()
+
+    fileListMock.current = { files: [`docs/${query}`], loading: false, loadError: null }
+    renderEntry({ onOpenEntry })
+    expect(container.querySelector('[aria-selected="true"]')?.textContent).toContain('Open file')
+    submit()
+    expect(onOpenEntry).toHaveBeenCalledWith(
+      expect.objectContaining({
+        classification: {
+          kind: 'existing-file',
+          matchKind: 'exact-basename',
+          relativePath: `docs/${query}`
+        }
+      })
+    )
+  })
+
   it('tracks the configured provider and submits its exact classification', () => {
     const onOpenEntry = vi.fn().mockResolvedValue(undefined)
     renderEntry({ onOpenEntry })

src/renderer/src/components/tab-bar/tab-create-entry-classifier.test.ts

@@ -194,9 +194,9 @@ describe('tab create entry classification', () => {
       relativePath: 'src/components/Button.tsx'
     })
     expect(classifyTabEntryQuery('btn', files)).toEqual({
-      kind: 'existing-file',
-      matchKind: 'fuzzy',
-      relativePath: 'src/components/Button.tsx'
+      kind: 'search',
+      engine: 'google',
+      query: 'btn'
     })
   })
 
@@ -212,6 +212,18 @@ describe('tab create entry classification', () => {
     ])
   })
 
+  it('keeps literal filename matches after an exact basename match', () => {
+    expect(
+      getTabEntryOptions('Makefile', readyFiles(['build/Makefile', 'build/Makefile.am'])).map(
+        (option) => option.classification
+      )
+    ).toEqual([
+      { kind: 'existing-file', matchKind: 'exact-basename', relativePath: 'build/Makefile' },
+      { kind: 'search', engine: 'google', query: 'Makefile' },
+      { kind: 'existing-file', matchKind: 'literal-basename', relativePath: 'build/Makefile.am' }
+    ])
+  })
+
   it('prefers creating typed file paths over fuzzy matches', () => {
     expect(
       getTabEntryOptions('read.md', readyFiles(['README.md'])).map(
@@ -224,7 +236,7 @@ describe('tab create entry classification', () => {
     ])
   })
 
-  it('keeps single-token quick-open matches ahead of search, but not phrases', () => {
+  it('keeps literal filename matches ahead of search, but not phrases', () => {
     expect(
       getTabEntryOptions('typescript', readyFiles(['docs/typescript-guide.md'])).map(
         (option) => option.classification
@@ -232,7 +244,7 @@ describe('tab create entry classification', () => {
     ).toEqual([
       {
         kind: 'existing-file',
-        matchKind: 'fuzzy',
+        matchKind: 'literal-basename',
         relativePath: 'docs/typescript-guide.md'
       },
       { kind: 'search', engine: 'google', query: 'typescript' },
@@ -260,7 +272,7 @@ describe('tab create entry classification', () => {
   })
 
   // Fuzzy matching is a subsequence scan, so a short token matches broadly.
-  it('keeps a search slot when fuzzy matches would fill the whole list', () => {
+  it('puts search ahead of fuzzy filename and path matches', () => {
     const files = [
       'src/components/Button.tsx',
       'src/lib/bootstrap-nav.ts',
@@ -269,15 +281,14 @@ describe('tab create entry classification', () => {
       'src/bin/tune.ts'
     ]
     expect(getTabEntryOptions('btn', readyFiles(files)).map((o) => o.classification.kind)).toEqual([
+      'search',
       'existing-file',
       'existing-file',
-      'existing-file',
-      'search'
+      'existing-file'
     ])
-    // A one-slot list still answers with the file, so Enter keeps quick-open.
     expect(
       getTabEntryOptions('btn', readyFiles(files), 1).map((o) => o.classification.kind)
-    ).toEqual(['existing-file'])
+    ).toEqual(['search'])
   })
 
   it('ranks search before ordinary create-file actions', () => {

src/renderer/src/components/tab-bar/tab-create-entry-classifier.ts

@@ -3,7 +3,11 @@ import type { RuntimeFileListState } from '../quick-open-file-list'
 import { translate } from '@/i18n/i18n'
 import { getTabEntryOmniboxPlaceholder } from './tab-create-entry-copy'
 import { DEFAULT_SEARCH_ENGINE, type SearchEngine } from '../../../../shared/browser-url'
-import { findExistingFileMatches, isLikelyNewFileIntent } from './tab-create-entry-file-matches'
+import {
+  findExistingFileMatches,
+  isLikelyNewFileIntent,
+  type ExistingFileMatch
+} from './tab-create-entry-file-matches'
 import { parseForcedSearchQuery } from './tab-create-entry-forced-search'
 import {
   isTabEntryAbsolutePathLike,
@@ -31,11 +35,7 @@ export const TAB_ENTRY_ABSOLUTE_PATH_REMOTE_BLOCKED_MESSAGE =
 export type TabEntryClassification =
   | { kind: 'empty'; message: string }
   | { kind: 'explicit-url'; url: string }
-  | {
-      kind: 'existing-file'
-      matchKind: 'exact-path' | 'exact-basename' | 'fuzzy'
-      relativePath: string
-    }
+  | ExistingFileMatch
   | { kind: 'host-url'; url: string }
   | { kind: 'search'; engine: SearchEngine; query: string }
   | { kind: 'new-file'; relativePath: string }
@@ -223,8 +223,9 @@ export function getTabEntryOptions(
     getPreparedQuickOpenFiles(fileList.files),
     Math.max(actionLimit, 1)
   )
-  const exactExistingFiles = existingFiles.filter((file) => file.matchKind !== 'fuzzy')
-  const fuzzyExistingFiles = existingFiles.filter((file) => file.matchKind === 'fuzzy')
+  const exactExistingFiles = existingFiles.filter(
+    (file) => file.matchKind === 'exact-path' || file.matchKind === 'exact-basename'
+  )
 
   if (exactExistingFiles.length > 0) {
     const options: TabEntryActionClassification[] = [...exactExistingFiles]
@@ -233,37 +234,41 @@ export function getTabEntryOptions(
     } else if (!hostUrl && newFile) {
       options.push(search)
     }
+    options.push(...existingFiles.filter((file) => file.matchKind === 'literal-basename'))
     return toOptions(options, actionLimit)
   }
   if (hostUrl?.kind === 'blocked') {
     return [blockedOption('invalid-url', hostUrl.message)]
   }
   if (hostUrl?.kind === 'host-url') {
-    return toOptions([hostUrl, ...fuzzyExistingFiles], actionLimit)
+    return toOptions([hostUrl, ...existingFiles], actionLimit)
   }
   if (pathError || !newFile) {
     // Why: an unusable path is still a live quick-open prefix — "src/" cannot be
     // created, but it matches real files, and dropping them turns every typed
     // separator into an error row mid-keystroke.
-    return fuzzyExistingFiles.length > 0
-      ? toOptions(fuzzyExistingFiles, actionLimit)
+    return existingFiles.length > 0
+      ? toOptions(existingFiles, actionLimit)
       : [invalidPathOption(pathError)]
   }
   if (isLikelyNewFileIntent(trimmed)) {
-    return toOptions([newFile, search, ...fuzzyExistingFiles], actionLimit)
+    return toOptions([newFile, search, ...existingFiles], actionLimit)
   }
   // Why no create row: a spaced, extension-less phrase is a web query, and a
   // stray arrow/click on "Create file" leaves an empty `release notes` on disk
   // that then outranks search as an exact match forever after.
   if (/\s/.test(trimmed)) {
-    return toOptions([search, ...fuzzyExistingFiles], actionLimit)
+    return toOptions([search, ...existingFiles], actionLimit)
   }
-  // Why: a single token is still a quick-open attempt ("btn" → Button.tsx), so
-  // only phrases promote web search over fuzzy matches. Fuzzy matching is a
-  // subsequence scan that fills every slot in a real repo, so hold one back —
-  // otherwise search silently disappears from the list it should always offer.
+  // Short Latin tokens match too many filenames to imply file intent; CJK words can be short.
+  if (/^[\p{Script=Latin}\p{Nd}]{1,2}$/u.test(trimmed.normalize('NFC'))) {
+    return toOptions([search, ...existingFiles, newFile], actionLimit)
+  }
+  const literalFiles = existingFiles.filter((file) => file.matchKind === 'literal-basename')
+  const fuzzyFiles = existingFiles.filter((file) => file.matchKind === 'fuzzy')
+  // Reserve a search slot even when literal filename matches fill the list.
   return toOptions(
-    [...fuzzyExistingFiles.slice(0, Math.max(actionLimit - 1, 1)), search, newFile],
+    [...literalFiles.slice(0, Math.max(actionLimit - 1, 1)), search, ...fuzzyFiles, newFile],
     actionLimit
   )
 }

src/renderer/src/components/tab-bar/tab-create-entry-file-matches.test.ts

@@ -2,6 +2,7 @@ import { expect, it, vi } from 'vitest'
 import { prepareQuickOpenFiles, rankQuickOpenFiles } from '../quick-open-search'
 import { findExistingFileMatches } from './tab-create-entry-file-matches'
 import type * as QuickOpenSearch from '../quick-open-search'
+import { compareFileNames } from '../../../../shared/file-name-sort'
 
 const ranking = vi.hoisted(() => ({ calls: 0 }))
 vi.mock('../quick-open-search', async (importOriginal) => {
@@ -28,6 +29,20 @@ it('skips fuzzy ranking when exact matches fill the requested window', () => {
   expect(ranking.calls).toBe(0)
 })
 
+it('selects literal filenames from a large inventory without running fuzzy ranking', () => {
+  const files = prepareQuickOpenFiles([
+    ...Array.from({ length: 100_000 }, (_, index) => `a/s/c/i/i/n/e/m/a/file-${index}.ts`),
+    'docs/asciinema-10.md',
+    'docs/asciinema-2.md'
+  ])
+  ranking.calls = 0
+  expect(findExistingFileMatches('asciinema', files, 2).map((file) => file.relativePath)).toEqual([
+    'docs/asciinema-2.md',
+    'docs/asciinema-10.md'
+  ])
+  expect(ranking.calls).toBe(0)
+})
+
 it('deduplicates exact paths and still fills remaining slots with fuzzy matches', () => {
   const files = prepareQuickOpenFiles(['a.md', 'a.md', 'other/a.md', 'abc.md'])
   expect(findExistingFileMatches('a.md', files, 4)).toEqual([
@@ -37,14 +52,12 @@ it('deduplicates exact paths and still fills remaining slots with fuzzy matches'
   ])
 })
 
-// Why: skipping the ranker is only sound because a fuzzy hit can never outrank an
-// exact one — exact results are concatenated first and dedupe is first-wins, so the
-// exact prefix is exactly what a full ranked-then-sliced list would have returned.
-// This re-runs the pre-skip pipeline and holds the shipped one to it.
+// Sort every literal candidate to check the bounded selection against a full reference.
 function rankThenSlice(
   query: string,
   files: readonly QuickOpenSearch.QuickOpenIndexedFile[],
-  limit: number
+  limit: number,
+  preferLiteralFilenames = false
 ): { kind: string; matchKind: string; relativePath: string }[] {
   const normalized = query.trim().replace(/\\/g, '/')
   if (!normalized || limit <= 0) {
@@ -56,6 +69,12 @@ function rankThenSlice(
     ...files
       .filter((f) => f.lowerFilename === lower)
       .map((f) => ['exact-basename', f.path] as const),
+    ...(preferLiteralFilenames
+      ? files
+          .filter((file) => file.lowerFilename.includes(lower))
+          .sort((a, b) => compareFileNames(a.path, b.path))
+          .map((file) => ['literal-basename', file.path] as const)
+      : []),
     ...rankQuickOpenFiles(normalized, files, limit).map((f) => ['fuzzy', f.path] as const)
   ]
   const seen = new Set<string>()
@@ -65,7 +84,7 @@ function rankThenSlice(
     .slice(0, limit)
 }
 
-it('returns what rank-then-slice would have returned, including at limit 1', () => {
+it('preserves quick-open ordering for explicit file and path queries, including at limit 1', () => {
   const corpus = [
     ['a.md', 'ab.md', 'abc.md', 'deep/nested/a.md'],
     ['ab.md', 'abc.md', 'deep/nested/a.md'],
@@ -74,7 +93,7 @@ it('returns what rank-then-slice would have returned, including at limit 1', ()
     ['README.md', 'docs/readme.md', 'readme.mdx'],
     ['only-fuzzy.md']
   ]
-  const queries = ['a.md', 'index.ts', 'readme.md', 'src/index.ts', 'a', 'nope.md']
+  const queries = ['a.md', 'index.ts', 'readme.md', 'src/index.ts', 'nope.md']
   for (const paths of corpus) {
     const files = prepareQuickOpenFiles(paths)
     for (const query of queries) {
@@ -90,6 +109,46 @@ it('returns what rank-then-slice would have returned, including at limit 1', ()
   }
 })
 
+it('matches the full literal-first reference for bare tokens across limits and input orders', () => {
+  const queries = ['a', 'ab', 'abc', 'BTN', 'button', 'asciinema', '工具', 'é']
+  for (const query of queries) {
+    const paths = [
+      ...Array.from({ length: 12 }, (_, index) => `${[...query].join('/')}/file-${index}.ts`),
+      `docs/${query}-10.md`,
+      `docs/${query}-2.md`,
+      `docs/${query}-2.md`,
+      `docs\\${query.toLowerCase()}-guide.md`,
+      `docs/a${'x'.repeat(120)}-${query.toUpperCase()}.md`,
+      'unrelated.txt'
+    ]
+    for (const corpus of [paths, [...paths, query, `docs/${query}`, query]]) {
+      for (const orderedPaths of [corpus, corpus.toReversed()]) {
+        const files = prepareQuickOpenFiles(orderedPaths)
+        for (const limit of [0, 1, 2, 3, 5, 20]) {
+          expect({
+            query,
+            limit,
+            matches: findExistingFileMatches(` ${query} `, files, limit)
+          }).toEqual({ query, limit, matches: rankThenSlice(query, files, limit, true) })
+        }
+      }
+    }
+  }
+})
+
+it('does not let duplicate literal candidates consume the result limit', () => {
+  const files = prepareQuickOpenFiles([
+    ...Array.from({ length: 10 }, () => 'docs/button-1.md'),
+    'docs/button-2.md'
+  ])
+  ranking.calls = 0
+  expect(findExistingFileMatches('button', files, 2)).toEqual([
+    { kind: 'existing-file', matchKind: 'literal-basename', relativePath: 'docs/button-1.md' },
+    { kind: 'existing-file', matchKind: 'literal-basename', relativePath: 'docs/button-2.md' }
+  ])
+  expect(ranking.calls).toBe(0)
+})
+
 it('takes the exact match at limit 1 without consulting the ranker at all', () => {
   const files = prepareQuickOpenFiles(['a.md', 'ab.md', 'abc.md', 'deep/nested/a.md'])
   ranking.calls = 0

src/renderer/src/components/tab-bar/tab-create-entry-file-matches.ts

@@ -1,8 +1,12 @@
-import { rankQuickOpenFiles, type QuickOpenIndexedFile } from '../quick-open-search'
+import {
+  QuickOpenPathRanker,
+  rankQuickOpenFiles,
+  type QuickOpenIndexedFile
+} from '../quick-open-search'
 
 export type ExistingFileMatch = {
   kind: 'existing-file'
-  matchKind: 'exact-path' | 'exact-basename' | 'fuzzy'
+  matchKind: 'exact-path' | 'exact-basename' | 'literal-basename' | 'fuzzy'
   relativePath: string
 }
 
@@ -36,6 +40,27 @@ export function isLikelyNewFileIntent(query: string): boolean {
   return hasFilenameExtension(trimmed) || /^\.[^.].*$/.test(trimmed)
 }
 
+function findLiteralFilenameMatches(
+  query: string,
+  files: readonly QuickOpenIndexedFile[],
+  limit: number
+): ExistingFileMatch[] {
+  // Natural ordering avoids arbitrary fuzzy scores among literal filename matches.
+  const ranker = new QuickOpenPathRanker('', limit)
+  const seen = new Set<string>()
+  for (const file of files) {
+    if (file.lowerFilename.includes(query) && !seen.has(file.path)) {
+      seen.add(file.path)
+      ranker.consider(file.path)
+    }
+  }
+  return ranker.result().paths.map((relativePath) => ({
+    kind: 'existing-file',
+    matchKind: 'literal-basename',
+    relativePath
+  }))
+}
+
 function dedupeMatches(matches: ExistingFileMatch[]): ExistingFileMatch[] {
   const seen = new Set<string>()
   return matches.filter((match) => {
@@ -75,11 +100,21 @@ export function findExistingFileMatches(
   if (exactMatches.length >= limit) {
     return exactMatches.slice(0, limit)
   }
+  const preferFilenames = !isLikelyNewFileIntent(normalizedQuery) && !/\s/.test(normalizedQuery)
+  const preferredMatches = preferFilenames
+    ? dedupeMatches([
+        ...exactMatches,
+        ...findLiteralFilenameMatches(lowerQuery, indexedFiles, limit)
+      ])
+    : exactMatches
+  if (preferredMatches.length >= limit) {
+    return preferredMatches.slice(0, limit)
+  }
   const fuzzyMatches = rankQuickOpenFiles(normalizedQuery, indexedFiles, limit).map((file) => ({
     kind: 'existing-file' as const,
     matchKind: 'fuzzy' as const,
     relativePath: file.path
   }))
 
-  return dedupeMatches([...exactMatches, ...fuzzyMatches]).slice(0, limit)
+  return dedupeMatches([...preferredMatches, ...fuzzyMatches]).slice(0, limit)
 }

src/renderer/src/components/tab-bar/tab-create-entry-history-placement.test.ts

@@ -2,10 +2,11 @@ import { describe, expect, it } from 'vitest'
 import { insertHistoryRowsBelowFileMatches } from './tab-create-entry-history-placement'
 import type { BrowserHistoryOmniboxRow } from './tab-create-entry-active-option'
 import type { TabEntryOption } from './tab-create-entry-action'
+import type { ExistingFileMatch } from './tab-create-entry-file-matches'
 
 function fileOption(
   relativePath: string,
-  matchKind: 'exact-path' | 'exact-basename' | 'fuzzy'
+  matchKind: ExistingFileMatch['matchKind']
 ): TabEntryOption {
   return {
     id: `existing-file:${relativePath}`,
@@ -40,7 +41,7 @@ describe('tab create entry history placement', () => {
     const placed = insertHistoryRowsBelowFileMatches(
       [
         fileOption('README.md', 'exact-basename'),
-        fileOption('docs/readme-notes.md', 'fuzzy'),
+        fileOption('docs/readme-notes.md', 'literal-basename'),
         newFileOption,
         searchOption
       ],
@@ -53,9 +54,9 @@ describe('tab create entry history placement', () => {
     expect(placed[3]).toMatchObject({ option: { id: 'new-file:readme' } })
   })
 
-  it('stays below a fuzzy match that is the only file row', () => {
+  it.each(['literal-basename', 'fuzzy'] as const)('stays below a lone %s file row', (matchKind) => {
     const placed = insertHistoryRowsBelowFileMatches(
-      [fileOption('docs/readme-notes.md', 'fuzzy'), searchOption],
+      [fileOption('docs/readme-notes.md', matchKind), searchOption],
       rows
     )
 

src/renderer/src/components/tab-bar/tab-create-entry-search-ranking.test.ts

@@ -0,0 +1,139 @@
+import { describe, expect, it } from 'vitest'
+import { classifyTabEntryQuery, getTabEntryOptions } from './tab-create-entry-classifier'
+import { prepareQuickOpenFiles } from '../quick-open-search'
+import { findExistingFileMatches } from './tab-create-entry-file-matches'
+
+const unrelatedFiles = [
+  'tests/e2e/terminal-split-activation-latency-main-probe.ts',
+  'src/main/linear/issue-context-inline-media.test.ts',
+  'src/renderer/src/components/editor/combined-diff/resolve-changes/combined-diff-section-cache-match.ts'
+]
+const readyFiles = (files: string[]) => ({ files, loading: false, loadError: null })
+
+describe('new-tab file matches versus web search', () => {
+  it('puts search ahead of scattered path matches for asciinema', () => {
+    const options = getTabEntryOptions('asciinema', readyFiles(unrelatedFiles))
+    expect(options.map((option) => option.classification.kind)).toEqual([
+      'search',
+      'existing-file',
+      'existing-file',
+      'existing-file'
+    ])
+    expect(classifyTabEntryQuery('asciinema', readyFiles(unrelatedFiles))).toEqual({
+      kind: 'search',
+      engine: 'google',
+      query: 'asciinema'
+    })
+  })
+
+  it('keeps an actual filename match ahead of search and weak matches below it', () => {
+    const options = getTabEntryOptions(
+      'asciinema',
+      readyFiles([...unrelatedFiles, 'docs/asciinema-guide.md'])
+    )
+    expect(options[0].classification).toMatchObject({
+      kind: 'existing-file',
+      relativePath: 'docs/asciinema-guide.md'
+    })
+    expect(options[1].classification.kind).toBe('search')
+    expect(options.slice(2).every((option) => option.classification.kind === 'existing-file')).toBe(
+      true
+    )
+  })
+
+  it.each([1, 2, 4, 8])('finds a literal filename before limiting to %i actions', (limit) => {
+    const files = readyFiles([
+      ...Array.from({ length: 10 }, (_, index) => `b/u/t/t/o/n/file-${index}.ts`),
+      'src/components/Button.tsx'
+    ])
+    expect(getTabEntryOptions('button', files, limit)[0].classification).toMatchObject({
+      kind: 'existing-file',
+      relativePath: 'src/components/Button.tsx'
+    })
+  })
+
+  it('offers fuzzy filename abbreviations below search', () => {
+    expect(
+      getTabEntryOptions('btn', readyFiles(['src/components/Button.tsx'])).map(
+        (option) => option.classification
+      )
+    ).toEqual([
+      { kind: 'search', engine: 'google', query: 'btn' },
+      { kind: 'existing-file', matchKind: 'fuzzy', relativePath: 'src/components/Button.tsx' },
+      { kind: 'new-file', relativePath: 'btn' }
+    ])
+  })
+
+  it('finds literal filenames even when their old fuzzy score falls outside the result limit', () => {
+    const target = `docs/a${'x'.repeat(120)}-asciinema.md`
+    const files = readyFiles([
+      ...Array.from({ length: 10 }, (_, index) => `a/s/c/i/i/n/e/m/a/file-${index}.ts`),
+      target
+    ])
+    expect(getTabEntryOptions('asciinema', files)[0].classification).toMatchObject({
+      kind: 'existing-file',
+      relativePath: target
+    })
+  })
+
+  it.each([
+    ['btn', 'src/components/Button.tsx', false],
+    ['button', 'src/components/Button.tsx', true],
+    ['asciinema', 'docs/ASCIINEMA-guide.md', true],
+    ['asciinema', 'docs\\ASCIINEMA-guide.md', true],
+    ['asciinema', `docs/a${'x'.repeat(120)}-asciinema.md`, true],
+    ['asciinema', unrelatedFiles[0], false],
+    ['asciinema', unrelatedFiles[1], false],
+    ['asciinema', unrelatedFiles[2], false],
+    ['abc', 'alphabet-biology-chemistry.md', false],
+    ['abc', 'a----b----c.md', false],
+    ['btn', 'src/base/tone.ts', false]
+  ])('reports literal filename matching for %s in %s', (query, path, matches) => {
+    const results = findExistingFileMatches(query, prepareQuickOpenFiles([path]), 1)
+    expect(results.some((result) => result.matchKind === 'literal-basename')).toBe(matches)
+  })
+
+  it.each(['a', 'AB', 'é', 'e\u0301', '12'])('puts search first for short token %s', (query) => {
+    const files = readyFiles(
+      Array.from({ length: 10 }, (_, index) => `docs/${query}-guide-${index}.md`)
+    )
+    for (const limit of [1, 2, 4, 8]) {
+      const options = getTabEntryOptions(query, files, limit)
+      expect(options[0].classification).toEqual({ kind: 'search', engine: 'google', query })
+      expect(options.slice(1).map((option) => option.classification)).toEqual(
+        Array.from({ length: limit - 1 }, (_, index) => ({
+          kind: 'existing-file',
+          matchKind: 'literal-basename',
+          relativePath: `docs/${query}-guide-${index}.md`
+        }))
+      )
+    }
+  })
+
+  it.each(['a', 'ab'])('keeps exact short filename %s ahead of search', (query) => {
+    for (const relativePath of [query, `docs/${query}`]) {
+      const files = readyFiles([`${query}-guide.md`, relativePath])
+      expect(classifyTabEntryQuery(query, files)).toEqual({
+        kind: 'existing-file',
+        matchKind: relativePath === query ? 'exact-path' : 'exact-basename',
+        relativePath
+      })
+    }
+  })
+
+  it.each(['文', '工具'])('keeps short CJK filename matches ahead of search for %s', (query) => {
+    expect(classifyTabEntryQuery(query, readyFiles([`docs/${query}指南.md`]))).toEqual({
+      kind: 'existing-file',
+      matchKind: 'literal-basename',
+      relativePath: `docs/${query}指南.md`
+    })
+  })
+
+  it('reserves search when literal filenames fill the list', () => {
+    const files = readyFiles(['button.tsx', 'button.css', 'button.test.ts', 'button.md'])
+    expect(getTabEntryOptions('button', files).map((option) => option.classification.kind)).toEqual(
+      ['existing-file', 'existing-file', 'existing-file', 'search']
+    )
+    expect(classifyTabEntryQuery('button', files).kind).toBe('existing-file')
+  })
+})