diff --git a/Makefile b/Makefile
index 881d06b0e..52534e123 100644
--- a/Makefile
+++ b/Makefile
@@ -9,9 +9,8 @@ all: parser.go
 test: parser.go
 	mv go.mod1 go.mod
 	mv go.sum1 go.sum
+	trap 'mv go.mod go.mod1;mv go.sum go.sum1' EXIT
 	GO111MODULE=on go test ./...
-	mv go.mod go.mod1
-	mv go.sum go.sum1
 
 parser.go: parser.y
 	make parser