From 6c0cbcf48025f57c25f172b8954f7460083c6c92 Mon Sep 17 00:00:00 2001
From: Kanishka <kanishkatn@gmail.com>
Date: Fri, 6 Oct 2023 13:19:54 +0530
Subject: [PATCH] address review comments

---
 dot/parachain/dispute/scraping/inclusion.go | 38 +++++++++++----------
 dot/parachain/dispute/scraping/scraping.go  | 13 ++++---
 2 files changed, 28 insertions(+), 23 deletions(-)

diff --git a/dot/parachain/dispute/scraping/inclusion.go b/dot/parachain/dispute/scraping/inclusion.go
index 25d0b78bf59..b160afd69d2 100644
--- a/dot/parachain/dispute/scraping/inclusion.go
+++ b/dot/parachain/dispute/scraping/inclusion.go
@@ -57,25 +57,27 @@ func (i *Inclusions) RemoveUpToHeight(blockNumber uint32, candidatesModified []c
 func (i *Inclusions) Get(candidateHash common.Hash) []Inclusion {
 	var inclusionsAsSlice []Inclusion
 	blocksIncluding, ok := i.inner[candidateHash]
-	if ok {
-		// Convert the map to a sorted slice for iteration
-		var sortedKeys []uint32
-		for h := range blocksIncluding {
-			sortedKeys = append(sortedKeys, h)
-		}
-		sort.Slice(sortedKeys, func(i, j int) bool {
-			return sortedKeys[i] < sortedKeys[j]
-		})
+	if !ok {
+		return inclusionsAsSlice
+	}
 
-		// Extract inclusions as a slice of structs
-		for _, height := range sortedKeys {
-			blocksAtHeight := blocksIncluding[height]
-			for _, block := range blocksAtHeight {
-				inclusionsAsSlice = append(inclusionsAsSlice, Inclusion{
-					BlockNumber: height,
-					BlockHash:   block,
-				})
-			}
+	// Convert the map to a sorted slice for iteration
+	var sortedKeys []uint32
+	for h := range blocksIncluding {
+		sortedKeys = append(sortedKeys, h)
+	}
+	sort.Slice(sortedKeys, func(i, j int) bool {
+		return sortedKeys[i] < sortedKeys[j]
+	})
+
+	// Extract inclusions as a slice of structs
+	for _, height := range sortedKeys {
+		blocksAtHeight := blocksIncluding[height]
+		for _, block := range blocksAtHeight {
+			inclusionsAsSlice = append(inclusionsAsSlice, Inclusion{
+				BlockNumber: height,
+				BlockHash:   block,
+			})
 		}
 	}
 
diff --git a/dot/parachain/dispute/scraping/scraping.go b/dot/parachain/dispute/scraping/scraping.go
index adc665e8bb0..d3de9d9e4af 100644
--- a/dot/parachain/dispute/scraping/scraping.go
+++ b/dot/parachain/dispute/scraping/scraping.go
@@ -70,7 +70,7 @@ func (cs *ChainScraper) ProcessActiveLeavesUpdate(
 	}
 
 	earliestBlockNumber := update.Activated.Number - uint32(len(ancestors))
-	var blockNumbers []uint32
+	blockNumbers := make([]uint32, 0, update.Activated.Number-earliestBlockNumber+1)
 	for i := update.Activated.Number; i >= earliestBlockNumber; i-- {
 		blockNumbers = append(blockNumbers, i)
 	}
@@ -129,6 +129,10 @@ func (cs *ChainScraper) ProcessCandidateEvents(
 		return nil, fmt.Errorf("getting candidate events: %w", err)
 	}
 
+	if events == nil {
+		return nil, nil
+	}
+
 	for _, event := range events.Types {
 		candidateEvents = append(candidateEvents, parachainTypes.CandidateEvent(event))
 	}
@@ -301,9 +305,8 @@ func getBlockAncestors(
 
 // saturatingSub returns the result of a - b, saturating at 0.
 func saturatingSub(a, b uint32) uint32 {
-	result := int(a) - int(b)
-	if result < 0 {
-		return 0
+	if a > b {
+		return a - b
 	}
-	return uint32(result)
+	return 0
 }