transform() — vite Function Reference

Source Code

packages/vite/src/node/server/pluginContainer.ts lines 529–620

  async transform(
    code: string,
    id: string,
    options?: {
      inMap?: SourceDescription['map']
      moduleType?: string
    },
  ): Promise<{
    code: string
    map: SourceMap | { mappings: '' } | null
    moduleType?: ModuleType
  }> {
    let ssr = this.environment.config.consumer === 'server'
    const topLevelConfig = this.environment.getTopLevelConfig()
    const optionsWithSSR = options
      ? { ...options, ssr, moduleType: options.moduleType ?? 'js' }
      : { ssr, moduleType: 'js' }
    const inMap = options?.inMap

    const ctx = new TransformPluginContext(this, id, code, inMap as SourceMap)
    ctx._addedImports = this._getAddedImports(id)

    for (const plugin of this.getSortedPlugins('transform')) {
      if (this._closed && this.environment.config.dev.recoverable)
        throwClosedServerError()

      const filter = getCachedFilterForPlugin(plugin, 'transform')
      if (filter && !filter(id, code, optionsWithSSR.moduleType)) continue

      if (
        isFutureDeprecationEnabled(
          topLevelConfig,
          'removePluginHookSsrArgument',
        )
      ) {
        Object.defineProperty(optionsWithSSR, 'ssr', {
          get() {
            warnFutureDeprecation(
              topLevelConfig,
              'removePluginHookSsrArgument',
              `Used in plugin "${plugin.name}".`,
            )
            return ssr
          },
          set(v) {
            ssr = v
          },
        })
      }

      ctx._updateActiveInfo(plugin, id, code)
      const start = debugPluginTransform ? performance.now() : 0
      let result: TransformResult | string | undefined
      const handler = getHookHandler(plugin.transform)
      try {
        result = await this.handleHookPromise(
          handler.call(ctx as any, code, id, optionsWithSSR),
        )
      } catch (e) {
        ctx.error(e)
      }
      if (!result) continue
      debugPluginTransform?.(
        timeFrom(start),
        plugin.name,
        prettifyUrl(id, this.environment.config.root),
      )
      if (isObject(result)) {
        if (result.code !== undefined) {
          code = result.code as string
          if (result.map) {
            if (debugSourcemapCombine) {
              // @ts-expect-error inject plugin name for debug purpose
              result.map.name = plugin.name
            }
            ctx.sourcemapChain.push(result.map)
          }
        }
        if (result.moduleType !== undefined) {
          optionsWithSSR.moduleType = result.moduleType
        }