Fixed importing the same directory twice

src/build/scanner/Scanner.go

@@ -11,4 +11,5 @@ type Scanner struct {
 	functions chan *core.Function
 	errors    chan error
 	group     sync.WaitGroup
+	queued    sync.Map
 }

src/build/scanner/queueDirectory.go

@@ -9,6 +9,12 @@ import (
 
 // queueDirectory queues an entire directory to be scanned.
 func (s *Scanner) queueDirectory(directory string, pkg string) {
+	_, loaded := s.queued.LoadOrStore(directory, nil)
+
+	if loaded {
+		return
+	}
+
 	err := fs.Walk(directory, func(name string) {
 		if !strings.HasSuffix(name, ".q") {
 			return