fix: adding checks to ensure coin denoms are sorted in Balance during Validate

CHANGELOG.md

@@ -93,6 +93,7 @@ Ref: https://keepachangelog.com/en/1.0.0/
 * (server) [#9704](https://github.com/cosmos/cosmos-sdk/pull/9704) Start GRPCWebServer in goroutine, avoid blocking other services from starting.
 * [\#9762](https://github.com/cosmos/cosmos-sdk/pull/9762) The init command uses the chain-id from the client config if --chain-id is not provided
 * [\#9793](https://github.com/cosmos/cosmos-sdk/pull/9793) Fixed ECDSA/secp256r1 transaction malleability.
+* [\#9829](https://github.com/cosmos/cosmos-sdk/pull/9829) Fixed Coin denom sorting not being checked during `Balance.Validate` check
 
 ### State Machine Breaking
 

x/bank/types/balance.go

@@ -30,33 +30,14 @@ func (b Balance) GetCoins() sdk.Coins {
 
 // Validate checks for address and coins correctness.
 func (b Balance) Validate() error {
-	_, err := sdk.AccAddressFromBech32(b.Address)
-	if err != nil {
+	if _, err := sdk.AccAddressFromBech32(b.Address); err != nil {
 		return err
 	}
-	seenDenoms := make(map[string]bool)
-
-	// NOTE: we perform a custom validation since the coins.Validate function
-	// errors on zero balance coins
-	for _, coin := range b.Coins {
-		if seenDenoms[coin.Denom] {
-			return fmt.Errorf("duplicate denomination %s", coin.Denom)
-		}
-
-		if err := sdk.ValidateDenom(coin.Denom); err != nil {
-			return err
-		}
 
-		if coin.IsNegative() {
-			return fmt.Errorf("coin %s amount is cannot be negative", coin.Denom)
-		}
-
-		seenDenoms[coin.Denom] = true
+	if err := b.Coins.Validate(); err != nil {
+		return err
 	}
 
-	// sort the coins post validation
-	b.Coins = b.Coins.Sort()
-
 	return nil
 }
 

x/bank/types/balance_test.go

@@ -64,6 +64,29 @@ func TestBalanceValidate(t *testing.T) {
 			},
 			true,
 		},
+		{
+			"0 value coin",
+			bank.Balance{
+				Address: "cosmos1yq8lgssgxlx9smjhes6ryjasmqmd3ts2559g0t",
+				Coins: sdk.Coins{
+					sdk.NewInt64Coin("atom", 0),
+					sdk.NewInt64Coin("zatom", 2),
+				},
+			},
+			true,
+		},
+		{
+			"unsorted coins",
+			bank.Balance{
+				Address: "cosmos1yq8lgssgxlx9smjhes6ryjasmqmd3ts2559g0t",
+				Coins: sdk.Coins{
+					sdk.NewInt64Coin("atom", 2),
+					sdk.NewInt64Coin("zatom", 2),
+					sdk.NewInt64Coin("batom", 12),
+				},
+			},
+			true,
+		},
 	}
 
 	for _, tc := range testCases {