From e9bf509c85e2d4d612741d566910f06e4a397bf8 Mon Sep 17 00:00:00 2001
From: teknomunk <teknomunk@protonmail.com>
Date: Sat, 31 Aug 2024 23:41:06 +0200
Subject: [PATCH] Add crash guards against unknown items (#4623)

This adds defensive checks to guard against crashing when digging with an unknown item in hand.

Reviewed-on: https://git.minetest.land/VoxeLibre/VoxeLibre/pulls/4623
Reviewed-by: the-real-herowl <the-real-herowl@noreply.git.minetest.land>
Co-authored-by: teknomunk <teknomunk@protonmail.com>
Co-committed-by: teknomunk <teknomunk@protonmail.com>
---
 mods/HELP/mcl_tt/snippets_base.lua | 6 ++++++
 mods/HELP/mcl_tt/snippets_mcl.lua  | 8 ++++++++
 2 files changed, 14 insertions(+)

diff --git a/mods/HELP/mcl_tt/snippets_base.lua b/mods/HELP/mcl_tt/snippets_base.lua
index f20f3dfe2..0468c50ac 100644
--- a/mods/HELP/mcl_tt/snippets_base.lua
+++ b/mods/HELP/mcl_tt/snippets_base.lua
@@ -37,6 +37,8 @@ end
 -- Digging capabilities of tool
 tt.register_snippet(function(itemstring, toolcaps, itemstack)
 	local def = minetest.registered_items[itemstring]
+	if not def then return end
+
 	if not toolcaps then
 		return
 	end
@@ -165,6 +167,8 @@ end)]]
 -- Food
 tt.register_snippet(function(itemstring)
 	local def = minetest.registered_items[itemstring]
+	if not def then return end
+
 	local desc
 	if def._tt_food then
 		desc = S("Food item")
@@ -179,6 +183,8 @@ end)
 -- Node info
 tt.register_snippet(function(itemstring)
 	local def = minetest.registered_items[itemstring]
+	if not def then return end
+
 	local desc = ""
 
 	-- Health-related node facts
diff --git a/mods/HELP/mcl_tt/snippets_mcl.lua b/mods/HELP/mcl_tt/snippets_mcl.lua
index 639422295..a964b96a3 100644
--- a/mods/HELP/mcl_tt/snippets_mcl.lua
+++ b/mods/HELP/mcl_tt/snippets_mcl.lua
@@ -64,6 +64,8 @@ end)
 
 tt.register_snippet(function(itemstring)
 	local def = minetest.registered_items[itemstring]
+	if not def then return end
+
 	local s = ""
 	if def.groups.eatable and def.groups.eatable > 0 then
 		s = s .. S("Hunger points: +@1", def.groups.eatable)
@@ -89,6 +91,8 @@ end)
 
 tt.register_snippet(function(itemstring)
 	local def = minetest.registered_items[itemstring]
+	if not def then return end
+
 	if def.groups.place_flowerlike == 1 then
 		return S("Grows on grass blocks or dirt")
 	elseif def.groups.place_flowerlike == 2 then
@@ -98,6 +102,8 @@ end)
 
 tt.register_snippet(function(itemstring)
 	local def = minetest.registered_items[itemstring]
+	if not def then return end
+
 	if def.groups.flammable then
 		return S("Flammable")
 	end
@@ -127,6 +133,8 @@ end)
 tt.register_snippet(function(itemstring, _, itemstack)
 	if not itemstack then return end
 	local def = itemstack:get_definition()
+	if not def then return end
+
 	if def.groups._mcl_potion ~= 1 then return end
 
 	local s = ""