diff --git a/cfg/lock_test.go b/cfg/lock_test.go
index 7f9ac95..63c035b 100644
--- a/cfg/lock_test.go
+++ b/cfg/lock_test.go
@@ -107,6 +107,6 @@
 	}
 
 	if !strings.Contains(string(out), expectSubpkgYaml) {
-		t.Errorf("Expected %q\nto contain\n%q")
+		t.Errorf("Expected %q\nto contain\n%q", string(out), expectSubpkgYaml)
 	}
 }