It is really weird:

PlayerInteractEvent#hasItem returns false for stone shovel while Material#STONE_SHOVEL#isItem returns true. See my code for clearer understanding.

if (!e.getAction().equals(Action.RIGHT_CLICK_BLOCK) || !e.hasBlock() || !e.hasItem())

{ new DebugMessage("Event cancelled because of no right-click/block/item"); #fired if (e.hasBlock()) new DebugMessage("Event got block!"); #fired if (e.hasItem()) new DebugMessage("Event got item!"); #did not fire if (Material.STONE_SHOVEL.isItem()) new DebugMessage("Stone_Shovel is item!"); #fired }

 

I added comments on which fired and which not (new DebugMessage is just a console message)

 

Please note that this bug persists for all other shovel types.