round outputs up on diffs

rainlanguage · Aug 11, 2024 · f14536c · f14536c
1 parent 5d81d70
commit f14536c
Showing 1 changed file with 5 additions and 1 deletion.
diff --git a/src/concrete/ob/OrderBook.sol b/src/concrete/ob/OrderBook.sol
@@ -872,7 +872,11 @@ contract OrderBook is IOrderBookV4, IMetaV1_2, ReentrancyGuard, Multicall, Order
             LibFixedPointDecimalScale.scale18(
                 output,
                 orderIOCalculation.context[CONTEXT_VAULT_OUTPUTS_COLUMN][CONTEXT_VAULT_IO_TOKEN_DECIMALS] / 1e18,
-                0
+                // Round outputs diff up if the scaling causes a rounding error.
+                // This only happens if the token has more than 18 decimals.
+                // Generally it's safer to overestimate output than
+                // underestimate.
+                FLAG_ROUND_UP
             );
         }