diff --git a/dumper_test.go b/dumper_test.go
index eec3f13..12b9270 100644
--- a/dumper_test.go
+++ b/dumper_test.go
@@ -784,7 +784,7 @@ func TestDumperPrint_Sprint_And_Fprint(t *testing.T) {
 
 type X int
 
-func (X) Write(p []byte) (n int, err error) {
+func (X) Write(_ []byte) (n int, err error) {
 	return 0, fmt.Errorf("foobar")
 }