Update pkg/machinery/scaffold.go

Co-authored-by: Copilot <175728472+Copilot@users.noreply.github.com>

Author: aman4433

pkg/machinery/scaffold.go

@@ -238,12 +238,20 @@ func (s Scaffold) updateFileModel(i Inserter, models map[string]*File) error {
 	m, err := s.loadPreviousModel(i, models)
 	if err != nil {
 		if os.IsNotExist(err) {
-			if withOptionalBehavior, ok := i.(HasIfNotExistsAction); ok &&
-				withOptionalBehavior.GetIfNotExistsAction() == IgnoreFile {
-				log.Warnf("Skipping missing file: %s", i.GetPath())
-				log.Warn("The code fragments will not be inserted.")
-				return nil
+			if withOptionalBehavior, ok := i.(HasIfNotExistsAction); ok {
+				switch withOptionalBehavior.GetIfNotExistsAction() {
+				case IgnoreFile:
+					log.Warnf("Skipping missing file: %s", i.GetPath())
+					log.Warn("The code fragments will not be inserted.")
+					return nil
+				case ErrorIfNotExist:
+					return err
+				default:
+					return err
+				}
 			}
+			// If HasIfNotExistsAction is not implemented, return the original error
+			return err
 		}
 		return fmt.Errorf("failed to load previous model for %s: %w", i.GetPath(), err)
 	}