adding initial localhost client testing (#3085)

* adding initial localhost client testing scaffolding

* add testing placeholders, adapt initialise code, wire AppModuleBasic

* adding happy path test cases, fixing store prefixing in verify membership/non-membership

* formatting

* adding additional test cases

* adding remaining test cases

* adding inline comments

modules/light-clients/09-localhost/client_state.go

@@ -9,6 +9,7 @@ import (
 	sdkerrors "github.com/cosmos/cosmos-sdk/types/errors"
 
 	clienttypes "github.com/cosmos/ibc-go/v7/modules/core/02-client/types"
+	commitmenttypes "github.com/cosmos/ibc-go/v7/modules/core/23-commitment/types"
 	host "github.com/cosmos/ibc-go/v7/modules/core/24-host"
 	"github.com/cosmos/ibc-go/v7/modules/core/exported"
 )
@@ -23,11 +24,6 @@ func NewClientState(chainID string, height clienttypes.Height) exported.ClientSt
 	}
 }
 
-// GetChainID returns the client state chain ID.
-func (cs ClientState) GetChainID() string {
-	return cs.ChainId
-}
-
 // ClientType returns the 09-localhost client type.
 func (cs ClientState) ClientType() string {
 	return exported.Localhost
@@ -95,7 +91,17 @@ func (cs ClientState) VerifyMembership(
 	path exported.Path,
 	value []byte,
 ) error {
-	bz := store.Get([]byte(path.String()))
+	merklePath, ok := path.(commitmenttypes.MerklePath)
+	if !ok {
+		return sdkerrors.Wrapf(clienttypes.ErrFailedChannelStateVerification, "todo: update error -- not found for path %s", path)
+	}
+
+	if len(merklePath.GetKeyPath()) != 2 {
+		return sdkerrors.Wrapf(clienttypes.ErrFailedChannelStateVerification, "todo: update error -- not found for path %s", path)
+	}
+
+	// The commitment prefix (eg: "ibc") is omitted when operating on the core IBC store
+	bz := store.Get([]byte(merklePath.KeyPath[1]))
 	if bz == nil {
 		return sdkerrors.Wrapf(clienttypes.ErrFailedChannelStateVerification, "todo: update error -- not found for path %s", path)
 	}
@@ -122,7 +128,17 @@ func (cs ClientState) VerifyNonMembership(
 	proof []byte,
 	path exported.Path,
 ) error {
-	bz := store.Get([]byte(path.String()))
+	merklePath, ok := path.(commitmenttypes.MerklePath)
+	if !ok {
+		return sdkerrors.Wrapf(clienttypes.ErrFailedChannelStateVerification, "todo: update error -- not found for path %s", path)
+	}
+
+	if len(merklePath.GetKeyPath()) != 2 {
+		return sdkerrors.Wrapf(clienttypes.ErrFailedChannelStateVerification, "todo: update error -- not found for path %s", path)
+	}
+
+	// The commitment prefix (eg: "ibc") is omitted when operating on the core IBC store
+	bz := store.Get([]byte(merklePath.KeyPath[1]))
 	if bz != nil {
 		return sdkerrors.Wrapf(clienttypes.ErrFailedChannelStateVerification, "todo: update error -- found for path %s", path)
 	}
@@ -153,8 +169,10 @@ func (cs ClientState) UpdateStateOnMisbehaviour(_ sdk.Context, _ codec.BinaryCod
 func (cs ClientState) UpdateState(ctx sdk.Context, cdc codec.BinaryCodec, clientStore sdk.KVStore, clientMsg exported.ClientMessage) []exported.Height {
 	height := clienttypes.GetSelfHeight(ctx)
 
-	clientState := NewClientState(ctx.ChainID(), height)
-	clientStore.Set([]byte(host.KeyClientState), clienttypes.MustMarshalClientState(cdc, clientState))
+	cs.ChainId = ctx.ChainID()
+	cs.LatestHeight = height
+
+	clientStore.Set([]byte(host.KeyClientState), clienttypes.MustMarshalClientState(cdc, &cs))
 
 	return []exported.Height{height}
 }