Refactor editor header file rename to a breadcrumb morph UI

- Display full breadcrumb (repo name + parent dirs) during rename for context
- Separate basename field from extension suffix to clarify what users edit
- Replace blur-to-commit with explicit confirm/cancel buttons
- Auto-attach extension to basename; respect explicitly typed extensions
- Add comprehensive tests for rename scenarios and edge cases

src/renderer/src/components/editor/EditorPanelHeaderPath.test.tsx

@@ -0,0 +1,221 @@
+// @vitest-environment happy-dom
+
+import { cleanup, fireEvent, render, screen } from '@testing-library/react'
+import { afterEach, beforeEach, describe, expect, it, vi } from 'vitest'
+import type { OpenFile } from '@/store/slices/editor'
+import { EditorPanelHeaderPath } from './EditorPanelHeaderPath'
+
+const renameFileOnDiskMock = vi.hoisted(() => vi.fn())
+
+vi.mock('@/store/selectors', () => ({
+  useWorktreeById: () => ({ path: '/repo', repoId: 'repo-1' })
+}))
+
+vi.mock('@/lib/rename-file', () => ({
+  renameFileOnDisk: renameFileOnDiskMock
+}))
+
+vi.mock('@/hooks/useShortcutLabel', () => ({
+  useShortcutLabel: () => ''
+}))
+
+vi.mock('@/i18n/i18n', async (importOriginal) => {
+  const actual = await importOriginal<typeof import('@/i18n/i18n')>() // eslint-disable-line @typescript-eslint/consistent-type-imports -- vi.mock requires an inline import
+  return {
+    ...actual,
+    translate: (_key: string, fallback: string, options?: { value0?: string }) =>
+      fallback.replace('{{value0}}', options?.value0 ?? '')
+  }
+})
+
+afterEach(cleanup)
+
+function baseFile(overrides: Partial<OpenFile> = {}): OpenFile {
+  return {
+    id: '/repo/notes.md',
+    filePath: '/repo/notes.md',
+    relativePath: 'notes.md',
+    worktreeId: 'wt-1',
+    language: 'markdown',
+    isDirty: false,
+    mode: 'edit',
+    ...overrides
+  }
+}
+
+function renderPath(file: OpenFile): void {
+  render(
+    <EditorPanelHeaderPath
+      activeFile={file}
+      copiedPathVisible={false}
+      canShowMarkdownPreview={false}
+      onCopyPath={vi.fn()}
+      onOpenMarkdownPreview={vi.fn()}
+      onOpenContainingFolder={vi.fn()}
+    />
+  )
+}
+
+function getRenameInput(label: string): HTMLInputElement {
+  const input = screen.getByLabelText(label)
+  if (!(input instanceof HTMLInputElement)) {
+    throw new Error(`Missing rename input: ${label}`)
+  }
+  return input
+}
+
+function openRenameInput(): void {
+  const pathRow = document.querySelector('.editor-header-path-row')
+  if (!pathRow) {
+    throw new Error('Missing editor header path row')
+  }
+  fireEvent.contextMenu(pathRow)
+  fireEvent.click(screen.getByRole('menuitem', { name: 'Rename' }))
+}
+
+describe('EditorPanelHeaderPath breadcrumb morph rename', () => {
+  beforeEach(() => {
+    renameFileOnDiskMock.mockReset()
+    Object.assign(window, { api: { ui: { writeClipboardText: vi.fn() } } })
+    vi.stubGlobal('requestAnimationFrame', (callback: FrameRequestCallback) => {
+      callback(0)
+      return 1
+    })
+    vi.stubGlobal('cancelAnimationFrame', vi.fn())
+  })
+
+  it('morphs into a breadcrumb strip with the basename editable', () => {
+    renderPath(baseFile())
+    openRenameInput()
+
+    const input = getRenameInput('Rename file notes.md')
+    expect(input.value).toBe('notes')
+    expect(screen.getByText('.md')).toBeDefined()
+    expect(screen.getByText('repo /')).toBeDefined()
+  })
+
+  it('shows the full crumb chain without ellipsis cuts', () => {
+    renderPath(
+      baseFile({
+        id: '/repo/docs/marketing/notes.md',
+        filePath: '/repo/docs/marketing/notes.md',
+        relativePath: 'docs/marketing/notes.md'
+      })
+    )
+    openRenameInput()
+
+    expect(screen.getByText('repo / docs / marketing /')).toBeDefined()
+  })
+
+  it('lets the strip claim the full header width instead of capping at 520px', () => {
+    renderPath(baseFile())
+    openRenameInput()
+
+    const input = getRenameInput('Rename file notes.md')
+    const strip = input.parentElement
+    if (!strip) {
+      throw new Error('Missing rename strip')
+    }
+    expect(strip.className).toContain('max-w-full')
+    expect(strip.className).not.toContain('520px')
+  })
+
+  it('selects the basename so typing replaces just the name', () => {
+    renderPath(baseFile())
+    openRenameInput()
+
+    const input = getRenameInput('Rename file notes.md')
+    expect(document.activeElement).toBe(input)
+    expect(input.selectionStart).toBe(0)
+    expect(input.selectionEnd).toBe('notes'.length)
+  })
+
+  it('re-attaches the pinned extension to a bare basename', () => {
+    renderPath(baseFile())
+    openRenameInput()
+
+    const input = getRenameInput('Rename file notes.md')
+    fireEvent.change(input, { target: { value: 'renamed' } })
+    fireEvent.keyDown(input, { key: 'Enter' })
+
+    expect(renameFileOnDiskMock).toHaveBeenCalledWith({
+      oldPath: '/repo/notes.md',
+      newName: 'renamed.md',
+      worktreeId: 'wt-1',
+      worktreePath: '/repo'
+    })
+  })
+
+  it('respects an explicitly typed extension without duplicating it', () => {
+    renderPath(baseFile())
+    openRenameInput()
+
+    const input = getRenameInput('Rename file notes.md')
+    fireEvent.change(input, { target: { value: 'renamed.mdx' } })
+    fireEvent.keyDown(input, { key: 'Enter' })
+
+    expect(renameFileOnDiskMock).toHaveBeenCalledWith(
+      expect.objectContaining({ newName: 'renamed.mdx' })
+    )
+  })
+
+  it('commits via the confirm button', () => {
+    renderPath(baseFile())
+    openRenameInput()
+
+    fireEvent.change(getRenameInput('Rename file notes.md'), {
+      target: { value: 'renamed.md' }
+    })
+    fireEvent.mouseDown(screen.getByRole('button', { name: 'Confirm rename' }))
+    fireEvent.click(screen.getByRole('button', { name: 'Confirm rename' }))
+
+    expect(renameFileOnDiskMock).toHaveBeenCalledTimes(1)
+    expect(renameFileOnDiskMock).toHaveBeenCalledWith(
+      expect.objectContaining({ newName: 'renamed.md' })
+    )
+  })
+
+  it('cancels via the cancel button without renaming', () => {
+    renderPath(baseFile())
+    openRenameInput()
+
+    fireEvent.change(getRenameInput('Rename file notes.md'), {
+      target: { value: 'renamed.md' }
+    })
+    fireEvent.mouseDown(screen.getByRole('button', { name: 'Cancel rename' }))
+    fireEvent.click(screen.getByRole('button', { name: 'Cancel rename' }))
+
+    expect(renameFileOnDiskMock).not.toHaveBeenCalled()
+    expect(screen.queryByLabelText('Rename file notes.md')).toBeNull()
+  })
+
+  it('cancels on Escape and ignores empty renames', () => {
+    renderPath(baseFile())
+    openRenameInput()
+
+    const input = getRenameInput('Rename file notes.md')
+    fireEvent.change(input, { target: { value: 'renamed.md' } })
+    fireEvent.keyDown(input, { key: 'Escape' })
+    expect(renameFileOnDiskMock).not.toHaveBeenCalled()
+    expect(screen.queryByLabelText('Rename file notes.md')).toBeNull()
+
+    openRenameInput()
+    fireEvent.change(getRenameInput('Rename file notes.md'), { target: { value: '   ' } })
+    fireEvent.keyDown(getRenameInput('Rename file notes.md'), { key: 'Enter' })
+    expect(renameFileOnDiskMock).not.toHaveBeenCalled()
+  })
+
+  it('selects the whole name when there is no extension', () => {
+    const file = baseFile({
+      id: '/repo/Makefile',
+      filePath: '/repo/Makefile',
+      relativePath: 'Makefile'
+    })
+    renderPath(file)
+    openRenameInput()
+
+    const input = getRenameInput('Rename file Makefile')
+    expect(input.selectionStart).toBe(0)
+    expect(input.selectionEnd).toBe('Makefile'.length)
+  })
+})

src/renderer/src/components/editor/EditorPanelHeaderPath.tsx

@@ -1,5 +1,5 @@
 import { useEffect, useRef, useState } from 'react'
-import { Copy, ExternalLink, Eye, Pencil } from 'lucide-react'
+import { Check, Copy, ExternalLink, Eye, Pencil, X } from 'lucide-react'
 import {
   DropdownMenu,
   DropdownMenuContent,
@@ -8,7 +8,6 @@ import {
   DropdownMenuShortcut,
   DropdownMenuTrigger
 } from '@/components/ui/dropdown-menu'
-import { Input } from '@/components/ui/input'
 import { useShortcutLabel } from '@/hooks/useShortcutLabel'
 import { translate } from '@/i18n/i18n'
 import type { OpenFile } from '@/store/slices/editor'
@@ -63,6 +62,9 @@ export function EditorPanelHeaderPath({
   const {
     canRename,
     currentFileName,
+    currentBaseName,
+    currentExtension,
+    breadcrumbSegments,
     isRenaming,
     renameInputRef,
     openRenameInput,
@@ -88,36 +90,96 @@ export function EditorPanelHeaderPath({
         }}
       >
         {isRenaming ? (
-          <Input
-            ref={renameInputRef}
-            data-editor-header-rename-input="true"
-            aria-label={translate(
-              'auto.components.editor.EditorPanelHeader.1bb1e226ec',
-              'Rename file {{value0}}',
-              { value0: currentFileName }
-            )}
-            defaultValue={currentFileName}
-            // Why: the header is narrow in floating mode; this keeps the
-            // edit field aligned with the path label without growing chrome.
-            className="h-6 w-[16ch] min-w-[104px] max-w-full rounded-sm bg-input/40 px-1.5 py-0 font-mono text-xs text-foreground md:text-xs focus-visible:ring-[1px]"
-            spellCheck={false}
-            onPointerDown={(event) => event.stopPropagation()}
-            onMouseDown={(event) => event.stopPropagation()}
-            onClick={(event) => event.stopPropagation()}
-            onDoubleClick={(event) => event.stopPropagation()}
-            onKeyDown={(event) => {
-              if (event.key === 'Enter') {
-                event.preventDefault()
-                event.stopPropagation()
-                commitRename()
-              } else if (event.key === 'Escape') {
-                event.preventDefault()
-                event.stopPropagation()
-                cancelRename()
-              }
-            }}
-            onBlur={commitRename}
-          />
+          <div className="flex h-6 w-full min-w-0 max-w-full items-center gap-1 rounded-md border border-accent/40 bg-input/40 py-0.5 pl-1.5 pr-1 focus-within:border-accent focus-within:ring-1 focus-within:ring-ring">
+            {breadcrumbSegments.length > 0 ? (
+              <span className="min-w-0 shrink truncate font-mono text-xs text-muted-foreground">
+                {breadcrumbSegments.join(' / ')} /
+              </span>
+            ) : null}
+            <input
+              ref={renameInputRef}
+              data-editor-header-rename-input="true"
+              aria-label={translate(
+                'auto.components.editor.EditorPanelHeader.1bb1e226ec',
+                'Rename file {{value0}}',
+                { value0: currentFileName }
+              )}
+              defaultValue={currentBaseName}
+              className="h-full min-w-0 flex-1 bg-transparent font-mono text-xs font-semibold text-foreground outline-none"
+              spellCheck={false}
+              onPointerDown={(event) => event.stopPropagation()}
+              onMouseDown={(event) => event.stopPropagation()}
+              onClick={(event) => event.stopPropagation()}
+              onDoubleClick={(event) => event.stopPropagation()}
+              onKeyDown={(event) => {
+                if (event.key === 'Enter') {
+                  event.preventDefault()
+                  event.stopPropagation()
+                  commitRename()
+                } else if (event.key === 'Escape') {
+                  event.preventDefault()
+                  event.stopPropagation()
+                  cancelRename()
+                }
+              }}
+              onBlur={commitRename}
+            />
+            {currentExtension ? (
+              <span className="shrink-0 font-mono text-xs text-muted-foreground">
+                {currentExtension}
+              </span>
+            ) : null}
+            <div className="flex shrink-0 items-center">
+              <button
+                type="button"
+                aria-label={translate(
+                  'auto.components.editor.EditorPanelHeader.confirmRename',
+                  'Confirm rename'
+                )}
+                title={translate(
+                  'auto.components.editor.EditorPanelHeader.confirmRename',
+                  'Confirm rename'
+                )}
+                className="flex size-5 items-center justify-center rounded text-status-success hover:bg-status-success-background"
+                onMouseDown={(event) => {
+                  // Why: preventDefault keeps focus in the input so clicking
+                  // confirm does not blur-commit first and double-rename.
+                  event.preventDefault()
+                  event.stopPropagation()
+                }}
+                onClick={(event) => {
+                  event.stopPropagation()
+                  commitRename()
+                }}
+              >
+                <Check className="size-3" strokeWidth={3} aria-hidden="true" />
+              </button>
+              <button
+                type="button"
+                aria-label={translate(
+                  'auto.components.editor.EditorPanelHeader.cancelRename',
+                  'Cancel rename'
+                )}
+                title={translate(
+                  'auto.components.editor.EditorPanelHeader.cancelRename',
+                  'Cancel rename'
+                )}
+                className="flex size-5 items-center justify-center rounded text-muted-foreground hover:bg-accent hover:text-foreground"
+                onMouseDown={(event) => {
+                  // Why: same as confirm — cancel must win over the input's
+                  // blur-commit when the pointer leaves the field.
+                  event.preventDefault()
+                  event.stopPropagation()
+                }}
+                onClick={(event) => {
+                  event.stopPropagation()
+                  cancelRename()
+                }}
+              >
+                <X className="size-3" strokeWidth={3} aria-hidden="true" />
+              </button>
+            </div>
+          </div>
         ) : (
           <button
             type="button"

src/renderer/src/components/editor/editor-header-file-rename.ts

@@ -2,13 +2,16 @@ import { useCallback, useRef, useState } from 'react'
 import type { RefCallback } from 'react'
 import type { OpenFile } from '@/store/slices/editor'
 import { useWorktreeById } from '@/store/selectors'
-import { basename } from '@/lib/path'
+import { basename, dirname } from '@/lib/path'
 import { renameFileOnDisk } from '@/lib/rename-file'
 import { getUntitledFileRoot } from './untitled-file-rename-path'
 
 type EditorHeaderFileRenameState = {
   canRename: boolean
   currentFileName: string
+  currentBaseName: string
+  currentExtension: string
+  breadcrumbSegments: string[]
   isRenaming: boolean
   renameInputRef: RefCallback<HTMLInputElement>
   openRenameInput: () => void
@@ -16,6 +19,40 @@ type EditorHeaderFileRenameState = {
   cancelRename: () => void
 }
 
+// Breadcrumb for the morph strip: worktree name plus parent dirs, so the
+// rename field keeps its location context without shifting header layout.
+function getBreadcrumbSegments(relativePath: string, worktreePath: string | null): string[] {
+  const segments: string[] = []
+  if (worktreePath) {
+    segments.push(basename(worktreePath))
+  }
+  if (relativePath) {
+    for (const part of dirname(relativePath).split('/')) {
+      if (part && part !== '.') {
+        segments.push(part)
+      }
+    }
+  }
+  return segments
+}
+
+// The morph input edits the basename while the extension stays pinned as a
+// suffix, so a bare name gets the extension re-attached. An explicitly typed
+// extension (same or different) is respected verbatim; null means no-op.
+export function resolveRenameTarget(
+  rawValue: string,
+  currentFileName: string,
+  currentExtension: string
+): string | null {
+  if (!rawValue || rawValue === currentFileName) {
+    return null
+  }
+  if (!currentExtension || rawValue.endsWith(currentExtension) || rawValue.includes('.')) {
+    return rawValue
+  }
+  return `${rawValue}${currentExtension}`
+}
+
 export function useEditorHeaderFileRename(activeFile: OpenFile): EditorHeaderFileRenameState {
   const worktree = useWorktreeById(activeFile.worktreeId)
   const [isRenaming, setIsRenaming] = useState(false)
@@ -23,6 +60,11 @@ export function useEditorHeaderFileRename(activeFile: OpenFile): EditorHeaderFil
   const renameCancelledRef = useRef(false)
   const renameFocusFrameRef = useRef<number | null>(null)
   const currentFileName = basename(activeFile.filePath)
+  const lastDotIndex = currentFileName.lastIndexOf('.')
+  const hasExtension = lastDotIndex > 0
+  const currentBaseName = hasExtension ? currentFileName.slice(0, lastDotIndex) : currentFileName
+  const currentExtension = hasExtension ? currentFileName.slice(lastDotIndex) : ''
+  const breadcrumbSegments = getBreadcrumbSegments(activeFile.relativePath, worktree?.path ?? null)
   // Why: read-only tabs (AI Vault View Log) are never renameable — rename would
   // rewrite the agent-owned artifact's backing path.
   const canRename =
@@ -50,12 +92,13 @@ export function useEditorHeaderFileRename(activeFile: OpenFile): EditorHeaderFil
       setIsRenaming(false)
       return
     }
-    const newName = input.value.trim()
+    const rawVal = input.value.trim()
     // onBlur follows Enter when the input unmounts; consume that trailing event
     // so one user action cannot start a second rename against the old path.
     renameCancelledRef.current = true
     setIsRenaming(false)
-    if (!newName || newName === currentFileName) {
+    const newName = resolveRenameTarget(rawVal, currentFileName, currentExtension)
+    if (!newName) {
       return
     }
     const worktreePath = getUntitledFileRoot(activeFile, worktree?.path ?? null)
@@ -89,27 +132,27 @@ export function useEditorHeaderFileRename(activeFile: OpenFile): EditorHeaderFil
       }
 
       // Why: focus belongs to the rename input mount; the frame preserves the
-      // previous timing so header layout settles before selecting text.
+      // previous timing so header layout settles before selecting text. The
+      // input holds the basename with the extension pinned alongside, so
+      // selecting all replaces the name without touching the suffix.
       renameFocusFrameRef.current = requestAnimationFrame(() => {
         renameFocusFrameRef.current = null
         if (renameInputElementRef.current !== el) {
           return
         }
         el.focus()
-        const dotIndex = currentFileName.lastIndexOf('.')
-        if (dotIndex > 0) {
-          el.setSelectionRange(0, dotIndex)
-        } else {
-          el.select()
-        }
+        el.select()
       })
     },
-    [clearRenameFocusFrame, currentFileName, isRenaming]
+    [clearRenameFocusFrame, isRenaming]
   )
 
   return {
     canRename,
     currentFileName,
+    currentBaseName,
+    currentExtension,
+    breadcrumbSegments,
     isRenaming,
     renameInputRef,
     openRenameInput,

src/renderer/src/components/tab-bar/EditorFileTab.tsx

@@ -298,8 +298,8 @@ export default function EditorFileTab({
             )}
             defaultValue={basename(file.filePath)}
             // Why: keep the inline field compact enough for the titlebar while
-            // giving filenames a little more room than the static tab label.
-            className="mr-1 h-5 w-[12ch] min-w-[72px] max-w-[132px] rounded-sm bg-input/40 px-1 py-0 text-xs text-foreground md:text-xs focus-visible:ring-[1px]"
+            // giving filenames more room to edit without premature truncation.
+            className="mr-1 h-5 w-[18ch] min-w-[96px] max-w-[200px] rounded-sm bg-input/40 px-1 py-0 text-xs text-foreground md:text-xs focus-visible:ring-[1px]"
             spellCheck={false}
             onPointerDown={(e) => e.stopPropagation()}
             onMouseDown={(e) => e.stopPropagation()}