From 45bab22cfa5c8e523711db724a446f5a815396cf Mon Sep 17 00:00:00 2001
From: beer-1 <beer-1@codingcats.xyz>
Date: Thu, 12 Dec 2024 16:21:19 +0900
Subject: [PATCH] create account if nft receipient account is not existing

---
 x/ibc/nft-transfer/keeper/integration_test.go | 39 ++++++++++++++++++-
 x/ibc/nft-transfer/keeper/relay.go            |  5 +++
 x/ibc/nft-transfer/types/expected_keeper.go   |  4 ++
 3 files changed, 46 insertions(+), 2 deletions(-)

diff --git a/x/ibc/nft-transfer/keeper/integration_test.go b/x/ibc/nft-transfer/keeper/integration_test.go
index 8bcf4444..91ff4615 100644
--- a/x/ibc/nft-transfer/keeper/integration_test.go
+++ b/x/ibc/nft-transfer/keeper/integration_test.go
@@ -1,10 +1,12 @@
 package keeper_test
 
 import (
+	"crypto/rand"
+
 	channeltypes "github.com/cosmos/ibc-go/v8/modules/core/04-channel/types"
 	host "github.com/cosmos/ibc-go/v8/modules/core/24-host"
 
-	sdktypes "github.com/cosmos/cosmos-sdk/types"
+	sdk "github.com/cosmos/cosmos-sdk/types"
 
 	"github.com/initia-labs/initia/x/ibc/nft-transfer/types"
 	ibctesting "github.com/initia-labs/initia/x/ibc/testing"
@@ -51,7 +53,7 @@ func (suite *KeeperTestSuite) CreateNftClass(
 
 func (suite *KeeperTestSuite) MintNft(
 	endpoint *ibctesting.Endpoint,
-	receiver sdktypes.AccAddress,
+	receiver sdk.AccAddress,
 	classId, className, tokenId, tokenUri, tokenData string,
 ) {
 	classNameBz, err := vmtypes.SerializeString(className)
@@ -224,6 +226,39 @@ func (suite *KeeperTestSuite) TestSendAndReceive() {
 			suite.ConfirmClassId(pathA2B.EndpointA, classId, targetClassId)
 		}
 	})
+
+	// transfer from chainA to chainB (non-existing account)
+	suite.Run("transfer A->B (non-existing account)", func() {
+		{
+			sender := pathA2B.EndpointA.Chain.SenderAccount.GetAddress()
+
+			// random receiver account
+			receiver := make(sdk.AccAddress, 20)
+			_, err := rand.Read(receiver)
+			suite.NoError(err)
+
+			packet = suite.transferNft(
+				pathA2B.EndpointA,
+				pathA2B.EndpointB,
+				targetClassId,
+				nftId,
+				sender.String(),
+				receiver.String(),
+			)
+
+			targetClassId = suite.receiverNft(
+				pathA2B.EndpointA,
+				pathA2B.EndpointB,
+				packet,
+			)
+
+			suite.ConfirmClassId(pathA2B.EndpointB, classId, targetClassId)
+
+			// receiver account should be created
+			suite.True(suite.chainB.App.GetAccountKeeper().HasAccount(suite.chainB.GetContext(), receiver))
+		}
+	})
+
 }
 
 func (suite *KeeperTestSuite) transferNft(
diff --git a/x/ibc/nft-transfer/keeper/relay.go b/x/ibc/nft-transfer/keeper/relay.go
index b8483e21..9f64e266 100644
--- a/x/ibc/nft-transfer/keeper/relay.go
+++ b/x/ibc/nft-transfer/keeper/relay.go
@@ -269,6 +269,11 @@ func (k Keeper) OnRecvPacket(ctx sdk.Context, packet channeltypes.Packet, data t
 		return err
 	}
 
+	// create account if receiver does not exist
+	if !k.authKeeper.HasAccount(ctx, receiver) {
+		k.authKeeper.SetAccount(ctx, k.authKeeper.NewAccountWithAddress(ctx, receiver))
+	}
+
 	labels := []metrics.Label{
 		telemetry.NewLabel(coretypes.LabelSourcePort, packet.GetSourcePort()),
 		telemetry.NewLabel(coretypes.LabelSourceChannel, packet.GetSourceChannel()),
diff --git a/x/ibc/nft-transfer/types/expected_keeper.go b/x/ibc/nft-transfer/types/expected_keeper.go
index 0e30a61f..b8d83b6c 100644
--- a/x/ibc/nft-transfer/types/expected_keeper.go
+++ b/x/ibc/nft-transfer/types/expected_keeper.go
@@ -18,6 +18,10 @@ type AccountKeeper interface {
 	AddressCodec() address.Codec
 	GetModuleAddress(name string) sdk.AccAddress
 	GetModuleAccount(ctx context.Context, name string) sdk.ModuleAccountI
+
+	SetAccount(ctx context.Context, acc sdk.AccountI)
+	HasAccount(ctx context.Context, addr sdk.AccAddress) bool
+	NewAccountWithAddress(ctx context.Context, addr sdk.AccAddress) sdk.AccountI
 }
 
 type NftKeeper interface {