⚡ perf(vscode): 预览切走标签页时页面留着，切回来不再重新生成、重发文档和整份重画

vscode/src/codeReader/editor/previewEditor.test.ts

@@ -6,16 +6,17 @@ import type { SymbolNode } from '../symbolLinks'
 import type { CodeColors } from '../theme/codeColors'
 import type { ExtensionToWebview, WebviewToExtension } from './messages'
 import { describe, expect, it, vi } from 'vitest'
-import { window, workspace } from 'vscode'
+import { commands, window, workspace } from 'vscode'
 import { documentMessage } from './documentMessage'
 import { documentSymbolNodes } from './documentSymbols'
-import { PreviewEditorProvider } from './previewEditor'
+import { OCCURRENCES_CONTEXT } from './occurrenceNavigation'
+import { PREVIEW_VIEW_TYPE, PreviewEditorProvider } from './previewEditor'
 
 vi.mock('vscode', () => ({
   commands: { executeCommand: vi.fn() },
-  window: { showErrorMessage: vi.fn() },
+  window: { showErrorMessage: vi.fn(), registerCustomEditorProvider: vi.fn() },
   workspace: {
-    onDidChangeTextDocument: () => ({ dispose: () => {} }),
+    onDidChangeTextDocument: vi.fn(() => ({ dispose: () => {} })),
     onDidChangeConfiguration: () => ({ dispose: () => {} }),
     getConfiguration: () => ({ get: (_key: string, fallback: unknown) => fallback }),
     openTextDocument: vi.fn(),
@@ -214,10 +215,10 @@ function opening(profiles = { ask: profileSet(''), rewrite: profileSet('') }, co
   return { provider, document, diffBase }
 }
 
-/** 一个标签页：收发消息、切走（页面被销毁，切回来重新加载、再发 ready） */
+/** 一个标签页：收发消息；切走、切回来时页面留着，VS Code 只报一声可见性变了 */
 function tab() {
   let receive: ((message: WebviewToExtension) => Promise<void>) | undefined
-  let viewStateChanged: (() => void) | undefined
+  const viewStateListeners: (() => void)[] = []
   const post = vi.fn<(message: ExtensionToWebview) => void>()
   const panel = {
     active: true,
@@ -231,20 +232,22 @@ function tab() {
         return { dispose: () => {} }
       },
     },
-    onDidChangeViewState: (listener: typeof viewStateChanged) => {
-      viewStateChanged = listener
+    onDidChangeViewState: (listener: () => void) => {
+      viewStateListeners.push(listener)
       return { dispose: () => {} }
     },
     onDidDispose: () => ({ dispose: () => {} }),
   }
+  const setVisible = (visible: boolean): void => {
+    panel.visible = visible
+    panel.active = visible
+    viewStateListeners.forEach(listener => listener())
+  }
   return {
     panel: panel as unknown as Parameters<PreviewEditorProvider['resolveCustomTextEditor']>[1],
     send: (message: WebviewToExtension) => receive!(message),
-    hide: () => {
-      panel.visible = false
-      viewStateChanged!()
-      panel.visible = true
-    },
+    hide: () => setVisible(false),
+    show: () => setVisible(true),
     posted: () => post.mock.calls.map(([message]) => message),
     clear: () => post.mockClear(),
   }
@@ -284,7 +287,7 @@ describe('预览对比什么看这个标签页是从哪儿打开的', () => {
     expect(diffBase).not.toHaveBeenCalledWith(document.uri, 'uncommitted')
   })
 
-  it('开着的预览再从主栏点开就不比，再从「未提交的更改」点开又比；只切标签页不变', async () => {
+  it('开着的预览再从主栏点开就不比，再从「未提交的更改」点开又比；页面重新加载后按它记着的照旧比', async () => {
     const { provider, document } = opening()
     const page = tab()
     await provider.open(document.uri as never, { from: 'uncommitted' }, async () => provider.resolveCustomTextEditor(document as never, page.panel))
@@ -301,7 +304,6 @@ describe('预览对比什么看这个标签页是从哪儿打开的', () => {
     expect(page.posted()).toContainEqual({ type: 'openedFrom', from: 'uncommitted' })
     await vi.waitFor(() => expect(page.posted()).toContainEqual(comparedWithHead))
 
-    page.hide()
     page.clear()
     await page.send({ type: 'ready', openedFrom: 'uncommitted' })
     expect(page.posted()).toContainEqual({ type: 'openedFrom', from: 'uncommitted' })
@@ -336,6 +338,67 @@ describe('预览对比什么看这个标签页是从哪儿打开的', () => {
   })
 })
 
+describe('标签页切走时页面留着', () => {
+  it('注册时就让页面在标签页切走后留着', () => {
+    const { provider } = opening()
+    provider.register()
+    expect(window.registerCustomEditorProvider).toHaveBeenCalledWith(PREVIEW_VIEW_TYPE, provider, { webviewOptions: { retainContextWhenHidden: true } })
+  })
+
+  it('切走再切回来：不重新生成文档、什么都不重发，高亮照旧能用键盘跳', async () => {
+    const { provider, document } = opening()
+    const page = tab()
+    await provider.open(document.uri as never, { from: 'uncommitted' }, async () => provider.resolveCustomTextEditor(document as never, page.panel))
+    await page.send({ type: 'ready' })
+    await vi.waitFor(() => expect(page.posted()).toContainEqual(comparedWithHead))
+    await page.send({ type: 'occurrenceNavigation', available: true })
+
+    page.clear()
+    vi.mocked(documentMessage).mockClear()
+    vi.mocked(commands.executeCommand).mockClear()
+    page.hide()
+    page.show()
+    // 比连续输入合并重新解析的那一下（150ms）等得久
+    await new Promise(resolve => setTimeout(resolve, 200))
+    expect(documentMessage).not.toHaveBeenCalled()
+    expect(page.posted()).toEqual([])
+    expect(commands.executeCommand).not.toHaveBeenCalledWith('setContext', OCCURRENCES_CONTEXT, false)
+  })
+
+  it('切走期间文件在别处改了：照常把新的文档发给留着的页面', async () => {
+    const { provider, document } = opening()
+    const page = tab()
+    provider.resolveCustomTextEditor(document as never, page.panel)
+    await page.send({ type: 'ready' })
+
+    page.hide()
+    page.clear()
+    document.version = 2
+    const edited = vi.mocked(workspace.onDidChangeTextDocument).mock.calls.at(-1)![0]
+    edited({ document, contentChanges: [{ rangeOffset: 0, rangeLength: 0, text: '// ' }] } as never)
+    await vi.waitFor(() => expect(page.posted()).toContainEqual(expect.objectContaining({ type: 'document', version: 2 })))
+  })
+
+  it('页面真的重新加载了（webview 进程崩了重建、开发者重载）：再发 ready 时照旧整份发一遍', async () => {
+    const { provider, document } = opening()
+    const page = tab()
+    await provider.open(document.uri as never, { from: 'uncommitted' }, async () => provider.resolveCustomTextEditor(document as never, page.panel))
+    await page.send({ type: 'ready' })
+    await vi.waitFor(() => expect(page.posted()).toContainEqual(comparedWithHead))
+
+    page.clear()
+    vi.mocked(documentMessage).mockClear()
+    await page.send({ type: 'ready', openedFrom: 'uncommitted' })
+    expect(documentMessage).toHaveBeenCalled()
+    expect(page.posted().map(message => message.type)).toEqual(expect.arrayContaining(['openedFrom', 'filter', 'qa', 'codeColors', 'document']))
+    await vi.waitFor(() => {
+      expect(page.posted()).toContainEqual(comparedWithHead)
+      expect(page.posted()).toContainEqual(expect.objectContaining({ type: 'profiles', kind: 'ask' }))
+      expect(page.posted()).toContainEqual(expect.objectContaining({ type: 'profiles', kind: 'rewrite' }))
+    })
+  })
+})
+
 describe('代码配色跟着当前颜色主题', () => {
   it('ready 后先于第一份文档发；换了主题发给 ready 了的预览，还没 ready 的等 ready 时发眼下的', async () => {
     const colors = themeColors(COLORS)