Minor fixes

babylonchain · Jul 11, 2022 · a67398c · a67398c
1 parent f57244e
commit a67398c
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Showing 2 changed files with 11 additions and 5 deletions.
diff --git a/proto/babylon/btclightclient/event.proto b/proto/babylon/btclightclient/event.proto
@@ -6,12 +6,18 @@ import "babylon/btclightclient/btclightclient.proto";
 
 option go_package = "github.com/babylonchain/babylon/x/btclightclient/types";
 
-// EventBTCRollBack is emitted on Msg/InsertHeader
+// The header included in the event is the block in the history
+// of the current mainchain to which we are rolling back to.
+// In other words, there is one rollback event emitted per re-org, to the
+// greatest common ancestor of the old and the new fork.
 message EventBTCRollBack {
   BTCHeaderInfo header = 1;
 }
 
 // EventBTCRollForward is emitted on Msg/InsertHeader
+// The header included in the event is the one the main chain is extended with.
+// In the event of a reorg, each block on the new fork that comes after
+// the greatest common ancestor will have a corresponding roll forward event.
 message EventBTCRollForward {
   BTCHeaderInfo header = 1;
 }
diff --git a/x/btclightclient/keeper/state.go b/x/btclightclient/keeper/state.go
@@ -269,16 +269,16 @@ func (s HeadersState) GetHighestCommonAncestor(header1 *wire.BlockHeader, header
 }
 
 // GetInOrderAncestorsUntil returns the list of nodes starting from the child and ending with the block *before* the `ancestor`.
-func (s HeadersState) GetInOrderAncestorsUntil(child *wire.BlockHeader, parent *wire.BlockHeader) []*wire.BlockHeader {
+func (s HeadersState) GetInOrderAncestorsUntil(child *wire.BlockHeader, ancestor *wire.BlockHeader) []*wire.BlockHeader {
 	currentHeader := child
 
 	var ancestors []*wire.BlockHeader
 	ancestors = append(ancestors, child)
-	if isParent(child, parent) {
+	if isParent(child, ancestor) {
 		return ancestors
 	}
 	s.iterateReverseHeaders(func(header *wire.BlockHeader) bool {
-		if header.BlockHash() == parent.BlockHash() {
+		if header.BlockHash() == ancestor.BlockHash() {
 			return true
 		}
 		if header.BlockHash().String() == currentHeader.PrevBlock.String() {
@@ -313,7 +313,7 @@ func (s HeadersState) TipExists() bool {
 
 // updateLongestChain checks whether the tip should be updated and returns true if it does
 func (s HeadersState) updateLongestChain(header *wire.BlockHeader, cumulativeWork *big.Int) {
-	// If there is no existing tip, then the header is set as the tiBTCp
+	// If there is no existing tip, then the header is set as the tip
 	if !s.TipExists() {
 		s.CreateTip(header)
 		return