onRollupLog() — vite Function Reference

Source Code

packages/vite/src/node/build.ts lines 1061–1143

export function onRollupLog(
  level: LogLevel,
  log: RollupLog,
  environment: Environment,
): void {
  const debugLogger = createDebugger('vite:build')
  const viteLog: LogOrStringHandler = (logLeveling, rawLogging) => {
    const logging =
      typeof rawLogging === 'object' ? rawLogging : { message: rawLogging }

    if (logging.code === 'UNRESOLVED_IMPORT') {
      const id = logging.id
      const exporter = logging.exporter
      // throw unless it's commonjs external...
      if (!id || !id.endsWith('?commonjs-external')) {
        throw new Error(
          `[vite]: Rolldown failed to resolve import "${exporter}" from "${id}".\n` +
            `This is most likely unintended because it can break your application at runtime.\n` +
            `If you do want to externalize this module explicitly add it to\n` +
            `\`build.rollupOptions.external\``,
        )
      }
    }

    if (logLeveling === 'warn') {
      if (
        logging.plugin === 'rollup-plugin-dynamic-import-variables' &&
        dynamicImportWarningIgnoreList.some((msg) =>
          logging.message.includes(msg),
        )
      ) {
        return
      }

      if (warningIgnoreList.includes(logging.code!)) {
        return
      }
    }

    // append plugin name to align with Rollup's behavior
    let message = logging.message
    if (logging.plugin) {
      message = `[plugin ${logging.plugin}] ${message}`
    }

    switch (logLeveling) {
      case 'info':
        environment.logger.info(message)
        return
      case 'warn':
        environment.logger.warn(colors.yellow(message))
        return
      case 'error':
        environment.logger.error(colors.red(message))
        return
      case 'debug':
        debugLogger?.(message)
        return
      default:
        logLeveling satisfies never
        // fallback to info if a unknown log level is passed
        environment.logger.info(message)
        return
    }
  }

  clearLine()
  const userOnLog = environment.config.build.rollupOptions?.onLog
  const userOnWarn = environment.config.build.rollupOptions?.onwarn
  if (userOnLog) {
    if (userOnWarn) {
      const normalizedUserOnWarn = normalizeUserOnWarn(userOnWarn, viteLog)
      userOnLog(level, log, normalizedUserOnWarn)
    } else {
      userOnLog(level, log, viteLog)
    }
  } else if (userOnWarn) {
    const normalizedUserOnWarn = normalizeUserOnWarn(userOnWarn, viteLog)
    normalizedUserOnWarn(level, log)
  } else {
    viteLog(level, log)