code: function augmentConfigBasic(
    stylelint /*: stylelint$internalApi*/,
    config /*: stylelint$config*/,
    configDir /*: string*/,
    allowOverrides /*:: ?: boolean*/
  ) /*: Promise<stylelint$config>*/ {
    return Promise.resolve()
      .then(() => {
        if (!allowOverrides) return config;
  
        return _.merge(config, stylelint._options.configOverrides);
      })
      .then(augmentedConfig => {
        return extendConfig(stylelint, augmentedConfig, configDir);
      })
      .then(augmentedConfig => {
        return absolutizePaths(augmentedConfig, configDir);
      });
  }
docs: - Merges config and configOverrides - Makes all paths absolute - Merges extends