test: prevent environment variables from overriding config file values in tests

Added a loadEnvVars parameter to InitConfig to control whether environment
variables should be loaded via viper.AutomaticEnv(). In tests, environment
variables (like ND_MUSICFOLDER) were overriding values from config test files,
causing tests to fail when these variables were set in the developer's
environment. Now tests can pass loadEnvVars=false to isolate from the
environment while production code continues to use loadEnvVars=true.

Signed-off-by: Deluan <deluan@navidrome.org>

conf/configuration.go

@@ -617,7 +617,7 @@ func init() {
 	setViperDefaults()
 }
 
-func InitConfig(cfgFile string) {
+func InitConfig(cfgFile string, loadEnvVars bool) {
 	codecRegistry := viper.NewCodecRegistry()
 	_ = codecRegistry.RegisterCodec("ini", ini.Codec{
 		LoadOptions: ini.LoadOptions{
@@ -638,10 +638,12 @@ func InitConfig(cfgFile string) {
 	}
 
 	_ = viper.BindEnv("port")
-	viper.SetEnvPrefix("ND")
-	replacer := strings.NewReplacer(".", "_")
-	viper.SetEnvKeyReplacer(replacer)
-	viper.AutomaticEnv()
+	if loadEnvVars {
+		viper.SetEnvPrefix("ND")
+		replacer := strings.NewReplacer(".", "_")
+		viper.SetEnvKeyReplacer(replacer)
+		viper.AutomaticEnv()
+	}
 
 	err := viper.ReadInConfig()
 	if viper.ConfigFileUsed() != "" && err != nil {