vitest-dev/vitest · error · Error

Switch context is only available for WebDriverIO provider.

Error message

Switch context is only available for WebDriverIO provider.

What it means

After confirming a provider exists, `wdioSwitchContext` checks `provider.name === 'webdriverio'`. Frame-switching is a WebDriver-specific operation; Playwright and the preview provider manage frames differently and don't expose this RPC.

Source

Thrown at packages/browser/src/node/rpc.ts:332

        cancelCurrentRun(reason) {
          vitest.cancelCurrentRun(reason)
        },
        async resolveId(id, importer) {
          return mockResolver.resolveId(id, importer)
        },
        debug(...args) {
          vitest.logger.console.debug(...args)
        },
        getCountOfFailedTests() {
          return vitest.state.getCountOfFailedTests()
        },
        async wdioSwitchContext(direction) {
          const provider = project.browser!.provider
          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 as any).switchToTestFrame()
          }
          else {
            await (provider as any).switchToMainFrame()
          }
        },
        async triggerCommand(sessionId, command, testPath, payload) {
          debug?.('[%s] Triggering command "%s"', sessionId, command)
          const provider = project.browser!.provider
          if (!provider) {
            throw new Error('Commands are only available for browser tests.')
          }
          const context = Object.assign(
            {
              testPath,
              project,

View on GitHub (pinned to d568f8ce37)

Solutions

Switch the project's provider to `webdriverio` if you need WebDriver-style frame switching.
Replace the call with the Playwright/preview equivalent (e.g. `page.frameLocator(...)` or `page.mainFrame()`).
Gate the call behind a provider check (`server.provider === 'webdriverio'`).

Example fix

// before — under playwright provider
await switchToTestFrame()

// after — use provider-appropriate API
import { page } from 'vitest/browser'
await page.frameLocator('iframe').locator('#in').click()

Defensive patterns

Strategy: validation

Validate before calling

function isWebdriverioProvider(provider: { name?: string }): boolean {
  return provider?.name === 'webdriverio'
}

Type guard

const isWebdriverioProvider = (p: { name?: string }): p is { name: 'webdriverio' } =>
  p?.name === 'webdriverio'

Prevention

Use the WebDriverIO provider if you rely on WebDriver-style frame switching.
Replace with Playwright frame APIs (frameLocator) when on Playwright.
Guard helper code with `server.provider === 'webdriverio'`.

When it happens

Trigger: Calling `switchToTestFrame`/`switchToMainFrame` (via the `wdioSwitchContext` RPC) while running under Playwright or the preview provider.

Common situations: Migrating from WebDriverIO to Playwright without removing frame-switching calls; copy-pasted helpers from a WebDriverIO test suite into a Playwright project.

Related errors

AI-assisted analysis of vitest-dev/vitest@d568f8ce37 (2026-08-03). Data as JSON: /data/errors/9f8c1c017b454016.json. Report an issue: GitHub.