Index: binaries/data/mods/public/simulation/components/UnitAI.js
===================================================================
--- binaries/data/mods/public/simulation/components/UnitAI.js
+++ binaries/data/mods/public/simulation/components/UnitAI.js
@@ -533,6 +533,27 @@
 	},
 
 	"Order.Gather": function(msg) {
+
+		let cmpResourceGatherer = Engine.QueryInterface(this.entity, IID_ResourceGatherer);
+		if (msg.data.type.generic !== "treasure" && cmpResourceGatherer && !cmpResourceGatherer.CanCarryMore(msg.data.type.generic))
+		{
+			// If the unit is full go to the nearest dropsite instead of trying to gather.
+			let nearestDropsite = this.FindNearestDropsite(msg.data.type.generic);
+			// Oh no, couldn't find any drop sites. Give up on gathering.
+			if (!nearestDropsite)
+			{
+				this.FinishOrder();
+				return;
+			}
+
+			this.PushOrderFront("ReturnResource", {
+				"target": nearestDropsite,
+				"force": false,
+				"type": msg.data.type
+			});
+			return;
+		}
+
 		// If the target is still alive, we need to kill it first
 		if (this.MustKillGatherTarget(this.order.data.target))
 		{
@@ -2225,7 +2246,7 @@
 					"MovementUpdate": function(msg) {
 						// If it looks like the path is failing, and we are close enough (3 tiles) from wanted range
 						// stop anyways. This avoids pathing for an unreachable goal and reduces lag considerably.
-						if (msg.likelyFailure || 
+						if (msg.likelyFailure ||
 							msg.obstructed && this.RelaxedMaxRangeCheck(this.order.data, this.order.data.max + this.DefaultRelaxedMaxRange) ||
 							!msg.obstructed && this.CheckRange(this.order.data))
 							this.FinishOrder();
@@ -5647,7 +5668,7 @@
 	    this.workOrders.length && this.workOrders[0].type == "Trade")
 	{
 		let cmpTrader = Engine.QueryInterface(this.entity, IID_Trader);
-		if (cmpTrader.HasBothMarkets() && 
+		if (cmpTrader.HasBothMarkets() &&
 		   (cmpTrader.GetFirstMarket() == target && cmpTrader.GetSecondMarket() == source ||
 		    cmpTrader.GetFirstMarket() == source && cmpTrader.GetSecondMarket() == target))
 		{