Bad Bunny's giving golf tips to Happy Gilmore ... because the rapper is filming scenes with Adam Sandler for the upcoming sequel -- and it looks like he's a caddy.
Check out these behind-the-scenes photos from the set of Adam's "Happy Gilmore 2" ... Bad Bunny's in full costume and makeup, dressed up like a caddy on the golf course with Happy.
Adam's rocking the trademark 'HG' fit ... a Boston Bruins hockey jersey, baggy pants and some Timberland boots.