perf(browser): do wdio context switching only once per file

packages/browser/src/client/tester/context.ts

@@ -1,5 +1,4 @@
 import type { Options as TestingLibraryOptions, UserEvent as TestingLibraryUserEvent } from '@testing-library/user-event'
-import type { BrowserRPC } from '@vitest/browser/client'
 import type { RunnerTask } from 'vitest'
 import type {
   BrowserPage,
@@ -19,15 +18,11 @@ import { convertElementToCssSelector, ensureAwaited, getBrowserState, getWorkerS
 const state = () => getWorkerState()
 // @ts-expect-error not typed global
 const provider = __vitest_browser_runner__.provider
-function filepath() {
-  return getWorkerState().filepath || getWorkerState().current?.file?.filepath || undefined
-}
-const rpc = () => getWorkerState().rpc as any as BrowserRPC
 const sessionId = getBrowserState().sessionId
 const channel = new BroadcastChannel(`vitest:${sessionId}`)
 
 function triggerCommand<T>(command: string, ...args: any[]) {
-  return rpc().triggerCommand<T>(sessionId, command, filepath(), args)
+  return getBrowserState().commands.triggerCommand<T>(command, args)
 }
 
 export function createUserEvent(__tl_user_event_base__?: TestingLibraryUserEvent, options?: TestingLibraryOptions): UserEvent {
@@ -52,6 +47,10 @@ export function createUserEvent(__tl_user_event_base__?: TestingLibraryUserEvent
       return createUserEvent()
     },
     async cleanup() {
+      // avoid cleanup rpc call if there is nothing to cleanup
+      if (!keyboard.unreleased.length) {
+        return
+      }
       return ensureAwaited(async () => {
         await triggerCommand('__vitest_cleanup', keyboard)
         keyboard.unreleased = []
@@ -106,9 +105,7 @@ export function createUserEvent(__tl_user_event_base__?: TestingLibraryUserEvent
       })
     },
     tab(options: UserEventTabOptions = {}) {
-      return ensureAwaited(() => {
-        return triggerCommand('__vitest_tab', options)
-      })
+      return ensureAwaited(() => triggerCommand('__vitest_tab', options))
     },
     async keyboard(text: string) {
       return ensureAwaited(async () => {

packages/browser/src/client/tester/locators/index.ts

@@ -1,4 +1,3 @@
-import type { BrowserRPC } from '@vitest/browser/client'
 import type {
   LocatorByRoleOptions,
   LocatorOptions,
@@ -8,8 +7,6 @@ import type {
   UserEventFillOptions,
   UserEventHoverOptions,
 } from '@vitest/browser/context'
-import type { WorkerGlobalState } from 'vitest'
-import type { BrowserRunnerState } from '../../utils'
 import { page, server } from '@vitest/browser/context'
 import {
   getByAltTextSelector,
@@ -22,7 +19,7 @@ import {
   Ivya,
   type ParsedSelector,
 } from 'ivya'
-import { ensureAwaited, getBrowserState, getWorkerState } from '../../utils'
+import { ensureAwaited, getBrowserState } from '../../utils'
 import { getElementError } from '../public-utils'
 
 // we prefer using playwright locators because they are more powerful and support Shadow DOM
@@ -205,27 +202,10 @@ export abstract class Locator {
     return this.selector
   }
 
-  private get state(): BrowserRunnerState {
-    return getBrowserState()
-  }
-
-  private get worker(): WorkerGlobalState {
-    return getWorkerState()
-  }
-
-  private get rpc(): BrowserRPC {
-    return this.worker.rpc as any as BrowserRPC
-  }
-
   protected triggerCommand<T>(command: string, ...args: any[]): Promise<T> {
-    const filepath = this.worker.filepath
-      || this.worker.current?.file?.filepath
-      || undefined
-
-    return ensureAwaited(() => this.rpc.triggerCommand<T>(
-      this.state.sessionId,
+    const commands = getBrowserState().commands
+    return ensureAwaited(() => commands.triggerCommand<T>(
       command,
-      filepath,
       args,
     ))
   }

packages/browser/src/client/tester/tester.ts

@@ -1,7 +1,7 @@
 import { channel, client, onCancel } from '@vitest/browser/client'
-import { page, userEvent } from '@vitest/browser/context'
+import { page, server, userEvent } from '@vitest/browser/context'
 import { collectTests, setupCommonEnv, SpyModule, startCoverageInsideWorker, startTests, stopCoverageInsideWorker } from 'vitest/browser'
-import { executor, getBrowserState, getConfig, getWorkerState } from '../utils'
+import { CommandsManager, executor, getBrowserState, getConfig, getWorkerState } from '../utils'
 import { setupDialogsSpy } from './dialog'
 import { setupExpectDom } from './expect-element'
 import { setupConsoleLogSpy } from './logger'
@@ -34,6 +34,8 @@ async function prepareTestEnvironment(files: string[]) {
   state.onCancel = onCancel
   state.rpc = rpc as any
 
+  getBrowserState().commands = new CommandsManager()
+
   // TODO: expose `worker`
   const interceptor = createModuleMockerInterceptor()
   const mocker = new VitestBrowserClientMocker(
@@ -69,6 +71,8 @@ async function prepareTestEnvironment(files: string[]) {
     runner,
     config,
     state,
+    rpc,
+    commands: getBrowserState().commands,
   }
 }
 
@@ -113,12 +117,34 @@ async function executeTests(method: 'run' | 'collect', files: string[]) {
 
   debug('runner resolved successfully')
 
-  const { config, runner, state } = preparedData
+  const { config, runner, state, commands, rpc } = preparedData
 
   state.durations.prepare = performance.now() - state.durations.prepare
 
   debug('prepare time', state.durations.prepare, 'ms')
 
+  let contextSwitched = false
+
+  // webdiverio context depends on the iframe state, so we need to switch the context,
+  // we delay this in case the user doesn't use any userEvent commands to avoid the overhead
+  if (server.provider === 'webdriverio') {
+    let switchPromise: Promise<void> | null = null
+
+    commands.onCommand(async () => {
+      if (switchPromise) {
+        await switchPromise
+      }
+      // if this is the first command, make sure we switched the command context to an iframe
+      if (!contextSwitched) {
+        switchPromise = rpc.wdioSwitchContext('iframe').finally(() => {
+          switchPromise = null
+          contextSwitched = true
+        })
+        await switchPromise
+      }
+    })
+  }
+
   try {
     await Promise.all([
       setupCommonEnv(config),
@@ -151,6 +177,9 @@ async function executeTests(method: 'run' | 'collect', files: string[]) {
       // need to cleanup for each tester
       // since playwright keyboard API is stateful on page instance level
       await userEvent.cleanup()
+      if (contextSwitched) {
+        await rpc.wdioSwitchContext('parent')
+      }
     }
     catch (error: any) {
       await client.rpc.onUnhandledError({

packages/browser/src/client/utils.ts

@@ -1,4 +1,5 @@
 import type { SerializedConfig, WorkerGlobalState } from 'vitest'
+import type { BrowserRPC } from './client'
 
 export async function importId(id: string): Promise<any> {
   const name = `/@id/${id}`.replace(/\\/g, '/')
@@ -77,6 +78,7 @@ export interface BrowserRunnerState {
   method: 'run' | 'collect'
   runTests?: (tests: string[]) => Promise<void>
   createTesters?: (files: string[]) => Promise<void>
+  commands: CommandsManager
   cdp?: {
     on: (event: string, listener: (payload: any) => void) => void
     once: (event: string, listener: (payload: any) => void) => void
@@ -194,3 +196,22 @@ function getParent(el: Element) {
   }
   return parent
 }
+
+export class CommandsManager {
+  private _listeners: ((command: string, args: any[]) => void)[] = []
+
+  public onCommand(listener: (command: string, args: any[]) => void): void {
+    this._listeners.push(listener)
+  }
+
+  public async triggerCommand<T>(command: string, args: any[]): Promise<T> {
+    const state = getWorkerState()
+    const rpc = state.rpc as any as BrowserRPC
+    const { sessionId } = getBrowserState()
+    const filepath = state.filepath || state.current?.file?.filepath
+    if (this._listeners.length) {
+      await Promise.all(this._listeners.map(listener => listener(command, args)))
+    }
+    return rpc.triggerCommand<T>(sessionId, command, filepath, args)
+  }
+}

packages/browser/src/node/commands/keyboard.ts

@@ -54,6 +54,9 @@ export const keyboardCleanup: UserEventCommand<(state: KeyboardState) => Promise
   state,
 ) => {
   const { provider, sessionId } = context
+  if (!state.unreleased) {
+    return
+  }
   if (provider instanceof PlaywrightBrowserProvider) {
     const page = provider.getPage(sessionId)
     for (const key of state.unreleased) {

packages/browser/src/node/plugins/pluginContext.ts

@@ -32,15 +32,13 @@ async function generateContextFile(
   globalServer: ParentBrowserProject,
 ) {
   const commands = Object.keys(globalServer.commands)
-  const filepathCode
-    = '__vitest_worker__.filepath || __vitest_worker__.current?.file?.filepath || undefined'
   const provider = [...globalServer.children][0].provider || { name: 'preview' }
   const providerName = provider.name
 
   const commandsCode = commands
     .filter(command => !command.startsWith('__vitest'))
     .map((command) => {
-      return `    ["${command}"]: (...args) => rpc().triggerCommand(sessionId, "${command}", filepath(), args),`
+      return `    ["${command}"]: (...args) => __vitest_browser_runner__.commands.triggerCommand("${command}", args),`
     })
     .join('\n')
 
@@ -53,9 +51,6 @@ async function generateContextFile(
   return `
 import { page, createUserEvent, cdp } from '${distContextPath}'
 ${userEventNonProviderImport}
-const filepath = () => ${filepathCode}
-const rpc = () => __vitest_worker__.rpc
-const sessionId = __vitest_browser_runner__.sessionId
 
 export const server = {
   platform: ${JSON.stringify(process.platform)},

packages/browser/src/node/providers/webdriver.ts

@@ -37,7 +37,7 @@ export class WebdriverBrowserProvider implements BrowserProvider {
     this.options = options as RemoteOptions
   }
 
-  async beforeCommand(): Promise<void> {
+  async switchToTestFrame(): Promise<void> {
     const page = this.browser!
     const iframe = await page.findElement(
       'css selector',
@@ -46,7 +46,7 @@ export class WebdriverBrowserProvider implements BrowserProvider {
     await page.switchToFrame(iframe)
   }
 
-  async afterCommand(): Promise<void> {
+  async switchToMainFrame(): Promise<void> {
     await this.browser!.switchToParentFrame()
   }
 

packages/browser/src/node/rpc.ts

@@ -3,6 +3,7 @@ import type { ErrorWithDiff } from 'vitest'
 import type { BrowserCommandContext, ResolveSnapshotPathHandlerContext, TestProject } from 'vitest/node'
 import type { WebSocket } from 'ws'
 import type { ParentBrowserProject } from './projectParent'
+import type { WebdriverBrowserProvider } from './providers/webdriver'
 import type { BrowserServerState } from './state'
 import type { WebSocketBrowserEvents, WebSocketBrowserHandlers } from './types'
 import { existsSync, promises as fs } from 'node:fs'
@@ -203,6 +204,21 @@ export function setupBrowserRpc(globalServer: ParentBrowserProject): void {
         getCountOfFailedTests() {
           return vitest.state.getCountOfFailedTests()
         },
+        async wdioSwitchContext(direction) {
+          const provider = project.browser!.provider as WebdriverBrowserProvider
+          if (!provider) {
+            throw new Error('Commands are only available for browser tests.')
+          }
+          if (provider.name !== 'webdriverio') {
+            throw new Error('Switch context is only available for WebDriverIO provider.')
+          }
+          if (direction === 'iframe') {
+            await provider.switchToTestFrame()
+          }
+          else {
+            await provider.switchToMainFrame()
+          }
+        },
         async triggerCommand(sessionId, command, testPath, payload) {
           debug?.('[%s] Triggering command "%s"', sessionId, command)
           const provider = project.browser!.provider
@@ -213,7 +229,6 @@ export function setupBrowserRpc(globalServer: ParentBrowserProject): void {
           if (!commands || !commands[command]) {
             throw new Error(`Unknown command "${command}".`)
           }
-          await provider.beforeCommand?.(command, payload)
           const context = Object.assign(
             {
               testPath,
@@ -224,14 +239,7 @@ export function setupBrowserRpc(globalServer: ParentBrowserProject): void {
             },
             provider.getCommandsContext(sessionId),
           ) as any as BrowserCommandContext
-          let result
-          try {
-            result = await commands[command](context, ...payload)
-          }
-          finally {
-            await provider.afterCommand?.(command, payload)
-          }
-          return result
+          return await commands[command](context, ...payload)
         },
         finishBrowserTests(sessionId: string) {
           debug?.('[%s] Finishing browser tests for session', sessionId)

packages/browser/src/node/types.ts

@@ -39,6 +39,7 @@ export interface WebSocketBrowserHandlers {
   getBrowserFileSourceMap: (
     id: string
   ) => SourceMap | null | { mappings: '' } | undefined
+  wdioSwitchContext: (direction: 'iframe' | 'parent') => void
 
   // cdp
   sendCdpEvent: (sessionId: string, event: string, payload?: Record<string, unknown>) => unknown

packages/vitest/src/node/types/browser.ts

@@ -24,8 +24,6 @@ export interface BrowserProvider {
    */
   supportsParallelism: boolean
   getSupportedBrowsers: () => readonly string[]
-  beforeCommand?: (command: string, args: unknown[]) => Awaitable<void>
-  afterCommand?: (command: string, args: unknown[]) => Awaitable<void>
   getCommandsContext: (sessionId: string) => Record<string, unknown>
   openPage: (sessionId: string, url: string, beforeNavigate?: () => Promise<void>) => Promise<void>
   getCDPSession?: (sessionId: string) => Promise<CDPSession>