diff --git a/helpers_test.go b/helpers_test.go
new file mode 100644
index 0000000..a10a46c
--- /dev/null
+++ b/helpers_test.go
@@ -0,0 +1,12 @@
+package easyjson
+
+import "testing"
+
+func BenchmarkNilCheck(b *testing.B) {
+	var a *int
+	for i := 0; i < b.N; i++ {
+		if !isNilInterface(a) {
+			b.Fatal("expected it to be nil")
+		}
+	}
+}