Fix vendoring of package using go mod vendor

lua/dummy.go

@@ -0,0 +1,18 @@
+// +build dummy
+
+// This file is part of a workaround for `go mod vendor` which won't
+// vendor C files if there are no Go files in the same directory.
+// This prevents the C header files in lua/ from being vendored.
+//
+// This Go file imports the lua package where there is another
+// dummy.go file which is the second part of this workaround.
+//
+// These two files combined make it so `go mod vendor` behaves correctly.
+//
+// See this issue for reference: https://github.com/golang/go/issues/26366
+
+package lua
+
+import (
+	_ "github.com/aarzilli/golua/lua/lua"
+)

lua/lua/dummy.go

@@ -0,0 +1,7 @@
+// +build dummy
+
+// Package lua contains only a C header files.
+//
+// This Go file is part of a workaround for `go mod vendor`.
+// Please see the file dummy.go in the parent directory for more information.
+package lua