Fixed an autocrafting crash, fixes #1567

CHANGELOG.md

@@ -12,6 +12,7 @@
 - Fixed orientations of the Portable Grid (TeamSpen210)
 - Fixed crafting event in Crafting Grid being fired twice (raoulvdberge)
 - Fixed a crash when the Constructor tries to place a block when a multipart is attached to it (raoulvdberge)
+- Fixed an autocrafting crash (raoulvdberge)
 - Attempted to fix FPS drop on Grid sorting (raoulvdberge)
 - Disk Manipulator in fluid mode will now extract a bucket at a time instead of 1 mB (or 64 buckets at a time with a Stack Upgrade instead of 64 mB) (raoulvdberge)
 

src/main/java/com/raoulvdberge/refinedstorage/apiimpl/autocrafting/task/CraftingTask.java

@@ -249,16 +249,20 @@ public class CraftingTask implements ICraftingTask {
                         toCraft.add(inputCrafted);
                         actualInputs.add(inputCrafted);
 
-                        previousSteps.add(calculate(networkItems, networkFluids, inputPattern, toInsert));
+                        ICraftingStep step = calculate(networkItems, networkFluids, inputPattern, toInsert);
 
                         input.shrink(craftQuantity);
 
+                        if (step != null) {
+                            previousSteps.add(step);
+
                             if (recursedPattern == null) {
                                 // Calculate added all the crafted outputs toInsert
                                 // So we remove the ones we use from toInsert
                                 ItemStack inserted = toInsert.get(inputCrafted, compare);
                                 toInsert.remove(inserted, craftQuantity);
                             }
+                        }
                     } else {
                         // Fluid checks are with a stack size of one
                         ItemStack fluidCheck = ItemHandlerHelper.copyStackWithSize(input, 1);