chore: remove error return in IterateConsensusStateAscending (#1896)

* removing error return in tendermint store.go

* updating tests and legacy code

* updating changelog

Author: damiannolan

CHANGELOG.md

@@ -71,7 +71,8 @@ Ref: https://keepachangelog.com/en/1.0.0/
 * (06-solomachine) [\#1100](https://github.com/cosmos/ibc-go/pull/1100) Deprecate `ClientId` field in 06-solomachine `Misbehaviour` type. 
 * (07-tendermint) [\#1097](https://github.com/cosmos/ibc-go/pull/1097) Remove `GetClientID` function from 07-tendermint `Misbehaviour` type.
 * (07-tendermint) [\#1097](https://github.com/cosmos/ibc-go/pull/1097) Deprecate `ClientId` field in 07-tendermint `Misbehaviour` type.
-* (modules/core/exported) [\#1107](https://github.com/cosmos/ibc-go/pull/1107) Merging the `Header` and `Misbehaviour` interfaces into a single `ClientMessage` type
+* (modules/core/exported) [\#1107](https://github.com/cosmos/ibc-go/pull/1107) Merging the `Header` and `Misbehaviour` interfaces into a single `ClientMessage` type.
+* (07-tendermint) [\#1896](https://github.com/cosmos/ibc-go/pull/1896) Remove error return from `IterateConsensusStateAscending` in `07-tendermint`.
 
 ### State Machine Breaking
 

modules/core/02-client/legacy/v100/store.go

@@ -96,10 +96,7 @@ func MigrateStore(ctx sdk.Context, storeKey storetypes.StoreKey, cdc codec.Binar
 			// add iteration keys so pruning will be successful
 			addConsensusMetadata(ctx, clientStore)
 
-			if err = ibctm.PruneAllExpiredConsensusStates(ctx, clientStore, cdc, tmClientState); err != nil {
-				return err
-			}
-
+			ibctm.PruneAllExpiredConsensusStates(ctx, clientStore, cdc, tmClientState)
 		default:
 			continue
 		}

modules/light-clients/07-tendermint/store.go

@@ -215,18 +215,17 @@ func GetHeightFromIterationKey(iterKey []byte) exported.Height {
 
 // IterateConsensusStateAscending iterates through the consensus states in ascending order. It calls the provided
 // callback on each height, until stop=true is returned.
-func IterateConsensusStateAscending(clientStore sdk.KVStore, cb func(height exported.Height) (stop bool)) error {
+func IterateConsensusStateAscending(clientStore sdk.KVStore, cb func(height exported.Height) (stop bool)) {
 	iterator := sdk.KVStorePrefixIterator(clientStore, []byte(KeyIterateConsensusStatePrefix))
 	defer iterator.Close()
 
 	for ; iterator.Valid(); iterator.Next() {
 		iterKey := iterator.Key()
 		height := GetHeightFromIterationKey(iterKey)
 		if cb(height) {
-			return nil
+			break
 		}
 	}
-	return nil
 }
 
 // GetNextConsensusState returns the lowest consensus state that is larger than the given height.
@@ -278,7 +277,7 @@ func GetPreviousConsensusState(clientStore sdk.KVStore, cdc codec.BinaryCodec, h
 func PruneAllExpiredConsensusStates(
 	ctx sdk.Context, clientStore sdk.KVStore,
 	cdc codec.BinaryCodec, clientState *ClientState,
-) (err error) {
+) {
 	var heights []exported.Height
 
 	pruneCb := func(height exported.Height) bool {
@@ -294,17 +293,12 @@ func PruneAllExpiredConsensusStates(
 		return false
 	}
 
-	err = IterateConsensusStateAscending(clientStore, pruneCb)
-	if err != nil {
-		return err
-	}
+	IterateConsensusStateAscending(clientStore, pruneCb)
 
 	for _, height := range heights {
 		deleteConsensusState(clientStore, height)
 		deleteConsensusMetadata(clientStore, height)
 	}
-
-	return nil
 }
 
 // Helper function for GetNextConsensusState and GetPreviousConsensusState

modules/light-clients/07-tendermint/update.go

@@ -186,9 +186,7 @@ func (cs ClientState) pruneOldestConsensusState(ctx sdk.Context, cdc codec.Binar
 		return true
 	}
 
-	if err := IterateConsensusStateAscending(clientStore, pruneCb); err != nil {
-		panic(err)
-	}
+	IterateConsensusStateAscending(clientStore, pruneCb)
 
 	// if pruneHeight is set, delete consensus state and metadata
 	if pruneHeight != nil {

modules/light-clients/07-tendermint/update_test.go

@@ -488,8 +488,7 @@ func (suite *TendermintTestSuite) TestPruneConsensusState() {
 	}
 	ctx := path.EndpointA.Chain.GetContext()
 	clientStore := path.EndpointA.Chain.App.GetIBCKeeper().ClientKeeper.ClientStore(ctx, path.EndpointA.ClientID)
-	err := ibctm.IterateConsensusStateAscending(clientStore, getFirstHeightCb)
-	suite.Require().Nil(err)
+	ibctm.IterateConsensusStateAscending(clientStore, getFirstHeightCb)
 
 	// this height will be expired but not pruned
 	path.EndpointA.UpdateClient()