diff --git a/Tupfile.lua b/Tupfile.lua
index 40b36107..6698cce4 100644
--- a/Tupfile.lua
+++ b/Tupfile.lua
@@ -5,22 +5,22 @@ tup.include("util/tup-ext.lua")
 tup.include("util/pokemon.lua")
 
 for file in iglob{"src/models/front/*", "src/models/front-cosmetic/*"} do
-    local output = toPSSpriteID(decodeFS(tup.base(file))) .. "." .. tup.ext(file)
+    local output = toPSSpriteID(decodeBase(file)) .. "." .. tup.ext(file)
     tup.rule(file, "ln -s ../../../%f %o", "build/ps/ani/" .. output)
 end
 
 for file in iglob{"src/models/back/*", "src/models/back-cosmetic/*"} do
-    local output = toPSSpriteID(decodeFS(tup.base(file))) .. "." .. tup.ext(file)
+    local output = toPSSpriteID(decodeBase(file)) .. "." .. tup.ext(file)
     tup.rule(file, "ln -s ../../../%f %o", "build/ps/ani-back/" .. output)
 end
 
 for file in iglob{"src/models/shiny/*", "src/models/shiny-cosmetic/*"} do
-    local output = toPSSpriteID(decodeFS(tup.base(file))) .. "." .. tup.ext(file)
+    local output = toPSSpriteID(decodeBase(file)) .. "." .. tup.ext(file)
     tup.rule(file, "ln -s ../../../%f %o", "build/ps/ani-shiny/" .. output)
 end
 
 for file in iglob{"src/models/back-shiny/*", "src/models/back-shiny-cosmetic/*"} do
-    local output = toPSSpriteID(decodeFS(tup.base(file))) .. "." .. tup.ext(file)
+    local output = toPSSpriteID(decodeBase(file)) .. "." .. tup.ext(file)
     tup.rule(file, "ln -s ../../../%f %o", "build/ps/ani-back-shiny/" .. output)
 end
 
@@ -42,7 +42,7 @@ function twittersprite(input, output)
 end
 
 for file in iglob{"src/models/front/*"} do
-    local base = toSmogonAlias(decodeFS(tup.base(file)))
+    local base = toSmogonAlias(decodeBase(file))
     tup.foreach_rule(file, "ln -s ../../../%f %o", "build/smogon/xy/" .. base .. ".%e")
     fbsprite(file, "build/smogon/fbsprites/xy/" .. base .. ".png")
     twittersprite(file, "build/smogon/twittersprites/xy/" .. base .. ".png")
diff --git a/util/pokemon.lua b/util/pokemon.lua
index 644412c4..815c59f4 100644
--- a/util/pokemon.lua
+++ b/util/pokemon.lua
@@ -6,6 +6,10 @@ function decodeFS(filename)
                    end)
 end
 
+function decodeBase(filename)
+    return decodeFS(tup.base(filename))
+end
+
 function toPSID(name)
     name = name:lower()
     name = name:gsub("[^a-z0-9]+", '')