Merge pull request #12677 from Ghommie/Ghommie-cit830

Fixes items' skills list keys missing associated traits and improves modulability a little.

code/game/objects/items.dm

@@ -180,6 +180,11 @@ GLOBAL_VAR_INIT(embedpocalypse, FALSE) // if true, all items will be able to emb
 		if(damtype == "brute")
 			hitsound = "swing_hit"
 
+	if(used_skills)
+		for(var/path in used_skills)
+			var/datum/skill/S = GLOB.skill_datums[path]
+			LAZYADD(used_skills[path], S.skill_traits)
+
 /obj/item/Destroy()
 	item_flags &= ~DROPDEL	//prevent reqdels
 	if(ismob(loc))
@@ -848,7 +853,7 @@ GLOBAL_VAR_INIT(embedpocalypse, FALSE) // if true, all items will be able to emb
 
 // Called when a mob tries to use the item as a tool.
 // Handles most checks.
-/obj/item/proc/use_tool(atom/target, mob/living/user, delay, amount=0, volume=0, datum/callback/extra_checks, skill_gain_mult = 1, max_level = INFINITY)
+/obj/item/proc/use_tool(atom/target, mob/living/user, delay, amount=0, volume=0, datum/callback/extra_checks, skill_gain_mult = STD_USE_TOOL_MULT)
 	// No delay means there is no start message, and no reason to call tool_start_check before use_tool.
 	// Run the start check here so we wouldn't have to call it manually.
 	if(!delay && !tool_start_check(user, amount))
@@ -893,7 +898,8 @@ GLOBAL_VAR_INIT(embedpocalypse, FALSE) // if true, all items will be able to emb
 		for(var/skill in used_skills)
 			if(!(SKILL_TRAINING_TOOL in used_skills[skill]))
 				continue
-			user.mind.auto_gain_experience(skill, gain*skill_gain_mult, GET_STANDARD_LVL(max_level))
+			var/datum/skill/S = GLOB.skill_datums[skill]
+			user.mind.auto_gain_experience(skill, gain*skill_gain_mult*S.item_skill_gain_multi)
 
 	return TRUE