chore: change order of ops on nullifier validation

world-chain-builder/src/pool/validator.rs

@@ -131,19 +131,16 @@ where
         transaction: &Tx,
         payload: &PbhPayload,
     ) -> Result<(), TransactionValidationError> {
-        // Validate the root first to prevent invalidating a valid transaction with a root that has
-        // not landed on chain yet
         self.validate_root(payload)?;
+        let date = chrono::Utc::now();
+        self.validate_external_nullifier(date, payload)?;
 
         // Create db transaction and insert the nullifier hash
         // We do this first to prevent repeatedly validating the same transaction
         let db_tx = self.pbh_db.tx_mut()?;
         let mut cursor = db_tx.cursor_write::<ValidatedPbhTransactionTable>()?;
         cursor.insert(payload.nullifier_hash.to_be_bytes().into(), EmptyValue)?;
 
-        let date = chrono::Utc::now();
-        self.validate_external_nullifier(date, payload)?;
-
         let res = verify_proof(
             payload.root,
             payload.nullifier_hash,