Innacurate viper.SetConfigFile documentation or behaviour?

[Ozoniuss]

I'm a bit confused by the documentation of the viper.SetConfigFile function. It says that

// SetConfigFile explicitly defines the path, name and extension of the config file.
// Viper will use this and not check any of the config paths.
func SetConfigFile(in string) { v.SetConfigFile(in) }

At first glance, after reading "Viper will use this and not check any of the config paths", I would assume that if viper.SetConfigFile is used, then viper will ignore all the paths that were added via viper.AddConfigPath(). This seems to be true in the following example:

func main() {
	viper.SetConfigName("config")
	viper.SetConfigType("yml")
	viper.AddConfigPath(".")
        viper.SetConfigFile("config2.json")
	err := viper.ReadInConfig()
	if err != nil {
		panic(fmt.Errorf("fatal error config file: %w", err))
	}

	fmt.Println(viper.Get("number"))
}

The output I got for the value of number that I set in my config2.json file, as expected. However, it seems that when I call viper.SetConfigName() after viper.SetConfigFile(), it doesn't use the file set via viper.SetConfigFile(). So in the example:

func main() {
        viper.SetConfigFile("config2.json")
	viper.SetConfigName("config")
	viper.SetConfigType("yml")
	viper.AddConfigPath(".")
	err := viper.ReadInConfig()
	if err != nil {
		panic(fmt.Errorf("fatal error config file: %w", err))
	}

	fmt.Println(viper.Get("number"))
}

the output I get for the value of number is the one from config.yml, which is located in the current directory that is supposedly ignored.

The culprit seems to be viper.SetConfigName(), which removes the value of v.configFile. The other function viper.SetConfigFile() also writes that value.

Is this expected? From the documentation, I would've expected viper to read config2.json in both cases. Am I misinterpreting the documentation?