Function doTransform

packages/vite/src/node/server/transformRequest.ts:150–207

(
  environment: DevEnvironment,
  url: string,
  options: TransformOptionsInternal,
  timestamp: number,
)

}

async function doTransform(
  environment: DevEnvironment,
  url: string,
  options: TransformOptionsInternal,
  timestamp: number,
) {
  const { pluginContainer } = environment

  let module = await environment.moduleGraph.getModuleByUrl(url)
  if (module) {
    // try use cache from url
    const cached = await getCachedTransformResult(
      environment,
      url,
      module,
      timestamp,
    )
    if (cached) return cached
  }

  const resolved = module
    ? undefined
    : ((await pluginContainer.resolveId(url, undefined)) ?? undefined)

  // resolve
  const id = module?.id ?? resolved?.id ?? url

  module ??= environment.moduleGraph.getModuleById(id)
  if (module) {
    // if a different url maps to an existing loaded id,  make sure we relate this url to the id
    await environment.moduleGraph._ensureEntryFromUrl(url, undefined, resolved)
    // try use cache from id
    const cached = await getCachedTransformResult(
      environment,
      url,
      module,
      timestamp,
    )
    if (cached) return cached
  }

  const result = loadAndTransform(
    environment,
    id,
    url,
    options,
    timestamp,
    module,
    resolved,
  )

  const { depsOptimizer } = environment
  if (!depsOptimizer?.isOptimizedDepFile(id)) {
    environment._registerRequestProcessing(id, () => result)
  }

  return result
}