core/err: optionally unjoin errMult

Author: ignoramous

intra/core/err.go

@@ -43,6 +43,18 @@ func joinErr(uniq bool, errs ...error) error {
 	var all []error
 	var m map[error]struct{}
 
+	if false { // unjoin?
+		for _, err := range errs {
+			if err == nil {
+				continue
+			}
+			var merr *errMult
+			if errors.As(err, &merr) {
+				all = append(all, merr.Unwrap()...)
+			}
+		}
+	}
+
 	if uniq {
 		m = make(map[error]struct{}, len(errs))
 	}