code: function setConfig (argv) {
      var configLookup = {}
  
      // expand defaults/aliases, in-case any happen to reference
      // the config.json file.
      applyDefaultsAndAliases(configLookup, flags.aliases, defaults)
  
      Object.keys(flags.configs).forEach(function (configKey) {
        var configPath = argv[configKey] || configLookup[configKey]
        if (configPath) {
          try {
            var config = null
            var resolvedConfigPath = path.resolve(process.cwd(), configPath)
  
            if (typeof flags.configs[configKey] === 'function') {
              try {
                config = flags.configs[configKey](resolvedConfigPath)
              } catch (e) {
                config = e
              }
              if (config instanceof Error) {
                error = config
                return
              }
            } else {
              config = require(resolvedConfigPath)
            }
  
            setConfigObject(config)
          } catch (ex) {
            if (argv[configKey]) error = Error(__('Invalid JSON config file: %s', configPath))
          }
        }
      })
    }
docs: set args from config.json file, this should be applied last so that defaults can be applied.