minetest.get_item_group - Uberi/MineTest-API GitHub Wiki
Get rating of a group of an item. (0 = not in group)
[integer](../type/integer.html) get_item_group([string](../type/string.html) name, [string](../type/string.html) group)
if minetest.get_item_group("bags:small", "bag_slots") > 3 then
print("small bag has more than 3 bag slots")
end