From fba7bd18f05e06a25d3a40d8d8664bd1726d935f Mon Sep 17 00:00:00 2001
From: Alexander Chepurnoy <alex.chepurnoy@iohk.io>
Date: Tue, 20 Sep 2022 14:20:04 +0300
Subject: [PATCH 1/2] removing Traverse.sequence

---
 .../nodeView/state/UtxoState.scala            | 22 +++++++++++++------
 1 file changed, 15 insertions(+), 7 deletions(-)

diff --git a/src/main/scala/org/ergoplatform/nodeView/state/UtxoState.scala b/src/main/scala/org/ergoplatform/nodeView/state/UtxoState.scala
index 7f73ead979..2c8798415d 100644
--- a/src/main/scala/org/ergoplatform/nodeView/state/UtxoState.scala
+++ b/src/main/scala/org/ergoplatform/nodeView/state/UtxoState.scala
@@ -1,7 +1,6 @@
 package org.ergoplatform.nodeView.state
 
 import java.io.File
-import cats.Traverse
 import org.ergoplatform.ErgoBox
 import org.ergoplatform.ErgoLikeContext.Height
 import org.ergoplatform.modifiers.history.header.Header
@@ -76,7 +75,6 @@ class UtxoState(override val persistentProver: PersistentBatchAVLProver[Digest32
                                        headerId: ModifierId,
                                        expectedDigest: ADDigest,
                                        currentStateContext: ErgoStateContext): Try[Unit] = {
-    import cats.implicits._
     val createdOutputs = transactions.flatMap(_.outputs).map(o => (ByteArrayWrapper(o.id), o)).toMap
 
     def checkBoxExistence(id: ErgoBox.BoxId): Try[ErgoBox] = createdOutputs
@@ -87,13 +85,23 @@ class UtxoState(override val persistentProver: PersistentBatchAVLProver[Digest32
     val txProcessing = ErgoState.execTransactions(transactions, currentStateContext)(checkBoxExistence)
     if (txProcessing.isValid) {
       log.debug(s"Cost of block $headerId (${currentStateContext.currentHeight}): ${txProcessing.payload.getOrElse(0)}")
-      val resultTry =
-        ErgoState.stateChanges(transactions).map { stateChanges =>
-          val mods = stateChanges.operations
-          Traverse[List].sequence(mods.map(persistentProver.performOneOperation).toList).map(_ => ())
+      val blockOpsTry = ErgoState.stateChanges(transactions).flatMap { stateChanges =>
+        val operations = stateChanges.operations
+        var opsResult: Try[Unit] = Success(())
+        operations.foreach { op =>
+          if (opsResult.isSuccess) {
+            persistentProver.performOneOperation(op) match {
+              case Success(_) =>
+              case Failure(t) =>
+                log.error(s"Operation $op failed during $headerId transactions validation in")
+                opsResult = Failure(t)
+            }
+          }
         }
+        opsResult
+      }
       ModifierValidator(stateContext.validationSettings)
-        .validateNoFailure(fbOperationFailed, resultTry, Transaction.ModifierTypeId)
+        .validateNoFailure(fbOperationFailed, blockOpsTry, Transaction.ModifierTypeId)
         .validateEquals(fbDigestIncorrect, expectedDigest, persistentProver.digest, headerId, Header.modifierTypeId)
         .result
         .toTry

From 8c862cabfc3c303cb0cc4d0fbb3334cee4de2fbe Mon Sep 17 00:00:00 2001
From: Alexander Chepurnoy <alex.chepurnoy@iohk.io>
Date: Tue, 20 Sep 2022 14:30:14 +0300
Subject: [PATCH 2/2] typo fixed

---
 src/main/scala/org/ergoplatform/nodeView/state/UtxoState.scala | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/main/scala/org/ergoplatform/nodeView/state/UtxoState.scala b/src/main/scala/org/ergoplatform/nodeView/state/UtxoState.scala
index 2c8798415d..b585c0bada 100644
--- a/src/main/scala/org/ergoplatform/nodeView/state/UtxoState.scala
+++ b/src/main/scala/org/ergoplatform/nodeView/state/UtxoState.scala
@@ -93,7 +93,7 @@ class UtxoState(override val persistentProver: PersistentBatchAVLProver[Digest32
             persistentProver.performOneOperation(op) match {
               case Success(_) =>
               case Failure(t) =>
-                log.error(s"Operation $op failed during $headerId transactions validation in")
+                log.error(s"Operation $op failed during $headerId transactions validation")
                 opsResult = Failure(t)
             }
           }