Function buildEnvironment

packages/vite/src/node/build.ts:813–922

* Build an App environment, or a App library (if libraryOptions is provided)

(
  environment: BuildEnvironment,
)

 * Build an App environment, or a App library (if libraryOptions is provided)
 **/
async function buildEnvironment(
  environment: BuildEnvironment,
): Promise<RolldownOutput | RolldownOutput[] | RolldownWatcher> {
  const { logger, config } = environment
  const { root, build: options } = config

  logger.info(
    colors.cyan(
      `vite v${VERSION} ${colors.green(
        `building ${environment.name} environment for ${environment.config.mode}...`,
      )}`,
    ),
  )

  let bundle: RolldownBuild | undefined
  let startTime: number | undefined
  try {
    const chunkMetadataMap = new ChunkMetadataMap()
    const rolldownOptions = resolveRolldownOptions(
      environment,
      chunkMetadataMap,
    )

    // watch file changes with rollup
    if (options.watch) {
      logger.info(colors.cyan(`\nwatching for file changes...`))

      const resolvedOutDirs = getResolvedOutDirs(
        root,
        options.outDir,
        options.rolldownOptions.output,
      )
      const emptyOutDir = resolveEmptyOutDir(
        options.emptyOutDir,
        root,
        resolvedOutDirs,
        logger,
      )
      const resolvedChokidarOptions = resolveChokidarOptions(
        {
          // @ts-expect-error chokidar option does not exist in rolldown but used for backward compat
          ...(rolldownOptions.watch || {}).chokidar,
          // @ts-expect-error chokidar option does not exist in rolldown but used for backward compat
          ...options.watch.chokidar,
        },
        resolvedOutDirs,
        emptyOutDir,
        environment.config.cacheDir,
      )

      const { watch } = await import('rolldown')
      const watcher = watch({
        ...rolldownOptions,
        watch: {
          ...rolldownOptions.watch,
          ...options.watch,
          watcher: convertToWatcherOptions(resolvedChokidarOptions),
        },