Fixes #4602: Prevent encoding invalid patterns and handle corrupted patterns a little more gracefully. (#4608) (#4629)

(cherry picked from commit 1f9707e256)
2020-08-21 19:24:47 +02:00
parent ef97381e5f
commit 98733844a6
4 changed files with 30 additions and 2 deletions
@@ -309,14 +309,27 @@ public class EncodedPatternItem extends AEBaseItem {
        final ListNBT tagIn = new ListNBT();
        final ListNBT tagOut = new ListNBT();

+        boolean hasInput = false;
        for (final ItemStack i : in) {
            tagIn.add(createItemTag(i));
+            if (!i.isEmpty()) {
+                hasInput = true;
+            }
        }

+        Preconditions.checkArgument(hasInput, "cannot encode a pattern that has no inputs.");
+
+        boolean hasNonEmptyOutput = false;
        for (final ItemStack i : out) {
            tagOut.add(createItemTag(i));
+            if (!i.isEmpty()) {
+                hasNonEmptyOutput = true;
+            }
        }

+        // Patterns without any outputs are corrupt! Never encode such a pattern.
+        Preconditions.checkArgument(hasNonEmptyOutput, "cannot encode a pattern that has no output.");
+
        encodedValue.put(EncodedPatternItem.NBT_INGREDIENTS, tagIn);
        encodedValue.put(EncodedPatternItem.NBT_PRODUCTS, tagOut);
        return encodedValue;