Function processWithPostCSS

packages/css/src/plugin.ts:449–501

(
  code: string,
  id: string,
  cleanId: string,
  deps: string[],
  config: CssPluginConfig,
  isModule: boolean,
)

}

async function processWithPostCSS(
  code: string,
  id: string,
  cleanId: string,
  deps: string[],
  config: CssPluginConfig,
  isModule: boolean,
): Promise<ProcessResult> {
  const lang = getPreprocessorLangFromId(id)

  if (lang) {
    const preResult = await compilePreprocessor(
      lang,
      code,
      cleanId,
      config.css.preprocessorOptions,
    )
    code = preResult.code
    deps.push(...preResult.deps)
  }

  const modulesConfig =
    typeof config.css.modules === 'object' ? config.css.modules : undefined

  const needInlineImport = code.includes('@import')
  const postcssResult = await runPostCSS(
    code,
    cleanId,
    config.css.postcss,
    config.cwd,
    needInlineImport,
    isModule ? { isModule: true, config: modulesConfig } : undefined,
    config.sourceMap,
  )
  code = postcssResult.code
  deps.push(...postcssResult.deps)

  const transformResult = await transformWithLightningCSS(code, cleanId, {
    target: config.css.target,
    lightningcss: config.css.lightningcss,
    minify: config.css.minify,
    sourceMap: config.sourceMap,
    inputSourceMap: postcssResult.map,
  })

  // When LightningCSS skips its transform (no targets/minify), it returns no
  // map; fall back to the PostCSS map so the chain still has one.
  return {
    code: transformResult.code,
    map: transformResult.map ?? postcssResult.map,
    modules: postcssResult.modules,
  }
}

function isEmptyChunkCode(code: string): boolean {
  return !code