Fixes #579 "Server Crash on startup"

CHANGELOG.md

@@ -5,6 +5,7 @@
 - Added support for JEI R and U keys in Grids (raoulvdberge)
 - Fixed crafting upgrade having weird behavior (raoulvdberge)
 - Fixed external storage not updating when loading chunk (raoulvdberge)
+- Fixed external storage crash (raoulvdberge)
 - Fixed weird autocrafting behavior (way2muchnoise)
 - Removed controller explosions when multiple controllers are connected to the same network (raoulvdberge)
 - You can now decompose storage disks if the item count is below zero by any chance (raoulvdberge)

src/main/java/com/raoulvdberge/refinedstorage/tile/externalstorage/ItemStorageExternal.java

@@ -58,10 +58,12 @@ public abstract class ItemStorageExternal implements IItemStorage {
             // In that case, we remove the items that have been removed due to the shrinkage
             if (cache.size() > newStacks.size()) {
                 for (int i = newStacks.size(); i < cache.size(); ++i) {
-                    ItemStack change = ItemHandlerHelper.copyStackWithSize(cache.get(i), -cache.get(i).stackSize);
+                    if (cache.get(i) != null) {
+                        ItemStack change = ItemHandlerHelper.copyStackWithSize(cache.get(i), -cache.get(i).stackSize);
 
-                    if (change != null) {
-                        changes.add(change);
+                        if (change != null) {
+                            changes.add(change);
+                        }
                     }
                 }
             }