diff --git a/src/testdir/test_lua.vim b/src/testdir/test_lua.vim
index 1a5c74f..7fcdad5 100644
--- a/src/testdir/test_lua.vim
+++ b/src/testdir/test_lua.vim
@@ -4,6 +4,11 @@
   finish
 endif
 
+func TearDown()
+  " Run garbage collection after each test to exercise luaV_setref().
+  call test_garbagecollect_now()
+endfunc
+
 " Check that switching to another buffer does not trigger ml_get error.
 func Test_command_new_no_ml_get_error()
   new