Function resolve

packages/vite/src/node/plugins/css.ts:1553–1587

(id, basedir, _importOptions, atRule)

    postcssPlugins.unshift(
      (await importPostcssImport()).default({
        async resolve(id, basedir, _importOptions, atRule) {
          const publicFile = checkPublicFile(
            id,
            environment.getTopLevelConfig(),
          )
          if (publicFile) {
            return publicFile
          }

          const resolved = await atImportResolvers.css(
            environment,
            id,
            class="cm">// The `source` is only absent for an `@import` injected by another plugin
            class="cm">// (a node with no source), in which case the resolver falls back to
            class="cm">// the project root.
            atRule.source?.input.file,
          )

          if (resolved) {
            return path.resolve(resolved)
          }

          class="cm">// postcss-import falls back to `resolve` dep if this is unresolved,
          class="cm">// but we've shimmed to remove the `resolve` dep to cut on bundle size.
          class="cm">// warn here to provide a better error message.
          if (!path.isAbsolute(id)) {
            environment.logger.error(
              colors.red(
                `Unable to resolve \`@import class="st">"${id}"\` from ${basedir}`,
              ),
            )
          }

          return id
        },
        async load(id) {
          const code = await fs.promises.readFile(id, class="st">'utf-8')
          const lang = CSS_LANGS_RE.exec(id)?.[1] as CssLang | undefined