Function setIframeViewport

packages/browser/src/client/orchestrator.ts:492–525

(
  iframe: HTMLIFrameElement,
  width: number,
  height: number,
)

}

async function setIframeViewport(
  iframe: HTMLIFrameElement,
  width: number,
  height: number,
) {
  const ui = getUiAPI()
  if (ui) {
    await ui.setIframeViewport(width, height)
  }
  else if (getBrowserState().provider === 'webdriverio') {
    iframe.parentElement?.setAttribute('data-scale', '1')
    await client.rpc.triggerCommand(
      getBrowserState().sessionId,
      '__vitest_viewport',
      undefined,
      [{ width, height }],
    )
  }
  else {
    const scale = Math.min(
      1,
      iframe.parentElement!.parentElement!.clientWidth / width,
      iframe.parentElement!.parentElement!.clientHeight / height,
    )
    iframe.parentElement!.style.cssText = `
      width: ${width}px;
      height: ${height}px;
      transform: scale(${scale});
      transform-origin: left top;
    `
    iframe.parentElement?.setAttribute('data-scale', String(scale))
    await new Promise(r => requestAnimationFrame(r))
  }
}

function debug(...args: unknown[]) {
  const debug = getConfig().env.VITEST_BROWSER_DEBUG