Tweek config and cache dir initialization

Check if enviroment variables are set instead if they are empty strings.
Don't care if the dir exists just take the path at face value.
Error if $HOME and the respective $XDG.. variables are not set.

main.go

@@ -10,29 +10,27 @@ import (
 	alpm "github.com/jguer/go-alpm"
 )
 
-func initPaths() {
-	if configHome = os.Getenv("XDG_CONFIG_HOME"); configHome != "" {
-		if info, err := os.Stat(configHome); err == nil && info.IsDir() {
-			configHome = filepath.Join(configHome, "yay")
-		} else {
-			configHome = filepath.Join(os.Getenv("HOME"), ".config/yay")
-		}
+func setPaths() error {
+	if _configHome, set := os.LookupEnv("XDG_CONFIG_HOME"); set {
+		cacheHome = filepath.Join(_configHome, "yay")
+	} else if _configHome, set := os.LookupEnv("HOME"); set {
+		cacheHome = filepath.Join(_configHome, ".config/yay")
 	} else {
-		configHome = filepath.Join(os.Getenv("HOME"), ".config/yay")
+		fmt.Errorf("XDG_CONFIG_HOME and HOME unset")
 	}
 
-	if cacheHome = os.Getenv("XDG_CACHE_HOME"); cacheHome != "" {
-		if info, err := os.Stat(cacheHome); err == nil && info.IsDir() {
-			cacheHome = filepath.Join(cacheHome, "yay")
-		} else {
-			cacheHome = filepath.Join(os.Getenv("HOME"), ".cache/yay")
-		}
+	if _cacheHome, set := os.LookupEnv("XDG_CACHE_HOME"); set {
+		cacheHome = filepath.Join(_cacheHome, "yay")
+	} else if _cacheHome, set := os.LookupEnv("HOME"); set {
+		cacheHome = filepath.Join(_cacheHome, ".cache/yay")
 	} else {
-		cacheHome = filepath.Join(os.Getenv("HOME"), ".cache/yay")
+		fmt.Errorf("XDG_CACHE_HOME and HOME unset")
 	}
 
 	configFile = filepath.Join(configHome, configFileName)
 	vcsFile = filepath.Join(cacheHome, vcsFileName)
+
+	return nil
 }
 
 func initConfig() (err error) {
@@ -184,7 +182,12 @@ func main() {
 		goto cleanup
 	}
 
-	initPaths()
+	err = setPaths()
+	if err != nil {
+		fmt.Println(err)
+		status = 1
+		goto cleanup
+	}
 
 	err = initConfig()
 	if err != nil {