diff --git a/bind/printer_test.go b/bind/printer_test.go
index c533f39..5c53567 100644
--- a/bind/printer_test.go
+++ b/bind/printer_test.go
@@ -49,7 +49,7 @@ impl 1
 impl 2
 `
 
-	str := string(out.Bytes())
+	str := out.String()
 	if !reflect.DeepEqual(str, want) {
 		t.Fatalf("error:\nwant=%q\ngot =%q\n", want, str)
 	}
diff --git a/main_test.go b/main_test.go
index 5ab6a11..a083b2e 100644
--- a/main_test.go
+++ b/main_test.go
@@ -66,7 +66,7 @@ func TestGovet(t *testing.T) {
 	cmd.Stderr = buf
 	err := cmd.Run()
 	if err != nil {
-		t.Fatalf("error running %s:\n%s\n%v", "go vet", string(buf.Bytes()), err)
+		t.Fatalf("error running %s:\n%s\n%v", "go vet", buf.String(), err)
 	}
 }
 
@@ -91,11 +91,11 @@ func TestGofmt(t *testing.T) {
 
 	err = cmd.Run()
 	if err != nil {
-		t.Fatalf("error running %s:\n%s\n%v", exe, string(buf.Bytes()), err)
+		t.Fatalf("error running %s:\n%s\n%v", exe, buf.String(), err)
 	}
 
 	if len(buf.Bytes()) != 0 {
-		t.Errorf("some files were not gofmt'ed:\n%s\n", string(buf.Bytes()))
+		t.Errorf("some files were not gofmt'ed:\n%s\n", buf.String())
 	}
 }