Save account for multi sending (#6674)

Include changes from PR #6283

Co-authored-by: Federico Kunze <31522760+fedekunze@users.noreply.github.com>
Co-authored-by: Alessio Treglia <alessio@tendermint.com>

CHANGELOG.md

@@ -355,7 +355,7 @@ to detail this new feature and how state transitions occur.
   now exists a single `Params` type with a getter and setter along with a getter for each individual parameter.
 
 ### Bug Fixes
-
+* (x/bank) [\#6674](https://github.com/cosmos/cosmos-sdk/pull/6674) Create account if recipient does not exist on handing `MsgMultiSend`.
 * (rest) [\#5508](https://github.com/cosmos/cosmos-sdk/pull/5508) Fix `x/distribution` endpoints to properly return height in the response.
 * (x/genutil) [\#5499](https://github.com/cosmos/cosmos-sdk/pull/) Ensure `DefaultGenesis` returns valid and non-nil default genesis state.
 * (client) [\#5303](https://github.com/cosmos/cosmos-sdk/issues/5303) Fix ignored error in tx generate only mode.

x/bank/internal/keeper/keeper.go

@@ -211,6 +211,15 @@ func (keeper BaseSendKeeper) InputOutputCoins(ctx sdk.Context, inputs []types.In
 				sdk.NewAttribute(sdk.AttributeKeyAmount, out.Coins.String()),
 			),
 		)
+
+		// Create account if recipient does not exist.
+		//
+		// NOTE: This should ultimately be removed in favor a more flexible approach
+		// such as delegated fee messages.
+		acc := keeper.ak.GetAccount(ctx, out.Address)
+		if acc == nil {
+			keeper.ak.SetAccount(ctx, keeper.ak.NewAccountWithAddress(ctx, out.Address))
+		}
 	}
 
 	return nil

x/bank/internal/keeper/keeper_test.go

@@ -149,6 +149,38 @@ func TestSendKeeper(t *testing.T) {
 	require.Error(t, err)
 }
 
+func TestInputOutputNewAccount(t *testing.T) {
+	app, ctx := createTestApp(false)
+	balances := sdk.NewCoins(sdk.NewInt64Coin("foo", 100), sdk.NewInt64Coin("bar", 50))
+	addr1 := sdk.AccAddress([]byte("addr1"))
+	acc1 := app.AccountKeeper.NewAccountWithAddress(ctx, addr1)
+
+	app.AccountKeeper.SetAccount(ctx, acc1)
+	require.NoError(t, app.BankKeeper.SetCoins(ctx, addr1, balances))
+
+	acc1Balances := app.BankKeeper.GetCoins(ctx, addr1)
+	require.Equal(t, balances, acc1Balances)
+
+	addr2 := sdk.AccAddress([]byte("addr2"))
+
+	require.Nil(t, app.AccountKeeper.GetAccount(ctx, addr2))
+	require.Empty(t, app.BankKeeper.GetCoins(ctx, addr2))
+
+	inputs := []types.Input{
+		{Address: addr1, Coins: sdk.NewCoins(sdk.NewInt64Coin("foo", 30), sdk.NewInt64Coin("bar", 10))},
+	}
+	outputs := []types.Output{
+		{Address: addr2, Coins: sdk.NewCoins(sdk.NewInt64Coin("foo", 30), sdk.NewInt64Coin("bar", 10))},
+	}
+
+	require.NoError(t, app.BankKeeper.InputOutputCoins(ctx, inputs, outputs))
+
+	expected := sdk.NewCoins(sdk.NewInt64Coin("foo", 30), sdk.NewInt64Coin("bar", 10))
+	acc2Balances := app.BankKeeper.GetCoins(ctx, addr2)
+	require.Equal(t, expected, acc2Balances)
+	require.NotNil(t, app.AccountKeeper.GetAccount(ctx, addr2))
+}
+
 func TestMsgSendEvents(t *testing.T) {
 	app, ctx := createTestApp(false)