code: function getUserRules(cosmiconfig) {
    const userConfig = cosmiconfig.config;
    const configPath = cosmiconfig.filepath;
  
    return (
      Promise.resolve()
        // Handle `extends`
        .then(() => {
          // If `extends` is defined, use stylelint's extends resolver
          if (!_.isEmpty(userConfig.extends)) {
            // We need this to fetch and merge all `extends` from the provided config
            // This will also merge the `rules` on top of the `extends` rules
            const linter = stylelint.createLinter();
  
            // stylelint used cosmiconfig v4 at version 9, bumped to v5 somewhere 9.x
            // So we pass both arguments to `load`, works in both versions
            return linter._extendExplorer.load(configPath, configPath);
          }
        })
        .then(extendedConfig => {
          const finalConfig = extendedConfig ? extendedConfig.config : userConfig;
  
          rules.userRulesNames = _.sortedUniq(_.keys(finalConfig.rules));
        })
    );
  }
docs: Get user rules
  Gather rules from `extends` as well