From 5c14b3bfbe1a594ae84870f7ea376533e286a8ba Mon Sep 17 00:00:00 2001
From: Joachim Stolberg <joe.stolberg@gmx.de>
Date: Sat, 7 Nov 2020 19:53:21 +0100
Subject: [PATCH] ta4_doser: Fix a bug that caused a server crash

---
 chemistry/ta4_doser.lua | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/chemistry/ta4_doser.lua b/chemistry/ta4_doser.lua
index 0888542..09fb175 100644
--- a/chemistry/ta4_doser.lua
+++ b/chemistry/ta4_doser.lua
@@ -157,7 +157,9 @@ local function untake(recipe, pos, liquids)
 	for _,item in pairs(recipe.input) do
 		if item.name ~= "" then
 			local outdir = liquids[item.name] or reload_liquids(pos)[item.name]
-			liquid.untake(pos, outdir, item.name, item.num)
+			if outdir then
+				liquid.untake(pos, outdir, item.name, item.num)
+			end
 		end
 	end
 end