add options

cmd/node-prune/main.go

@@ -22,15 +22,13 @@ func main() {
 
 	start := time.Now()
 
-	if dir == "" {
-		dir = "node_modules"
-	}
-
 	if *debug {
 		log.SetLevel(log.DebugLevel)
 	}
 
-	stats, err := prune.Prune(dir)
+	p := prune.New(prune.WithDir(dir))
+
+	stats, err := p.Prune()
 	if err != nil {
 		log.Fatalf("error: %s", err)
 	}

prune.go

@@ -22,9 +22,23 @@ type Pruner struct {
 	Log log.Interface
 }
 
-// Prune dir of unnecessary files.
-func Prune(dir string) (*Stats, error) {
-	return Pruner{dir, log.Log}.Prune()
+// Option function.
+type Option func(*Pruner)
+
+// New with the given options.
+func New(options ...Option) *Pruner {
+	v := &Pruner{Dir: "node_modules", Log: log.Log}
+	for _, o := range options {
+		o(v)
+	}
+	return v
+}
+
+// WithDir option.
+func WithDir(s string) Option {
+	return func(v *Pruner) {
+		v.Dir = s
+	}
 }
 
 // Prune performs the pruning.