feat: expose HasMetadata on bank Keeper (#10134)

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Add `HasMetaData` to bank keeper API.

---

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CHANGELOG.md

@@ -87,6 +87,7 @@ Ref: https://keepachangelog.com/en/1.0.0/
 
 ### Improvements
 
+* (x/bank) [\#10134](https://github.com/cosmos/cosmos-sdk/pull/10134) Add `HasDenomMetadata` function to bank `Keeper` to check if a client coin denom metadata exists in state.
 * (store) [\#10026](https://github.com/cosmos/cosmos-sdk/pull/10026) Improve CacheKVStore datastructures / algorithms, to no longer take O(N^2) time when interleaving iterators and insertions.
 * (types) [\#10076](https://github.com/cosmos/cosmos-sdk/pull/10076) Significantly speedup and lower allocations for `Coins.String()`.
 * (x/bank) [\#10022](https://github.com/cosmos/cosmos-sdk/pull/10022) `BankKeeper.SendCoins` now takes less execution time.

x/bank/keeper/keeper.go

@@ -28,6 +28,7 @@ type Keeper interface {
 	GetPaginatedTotalSupply(ctx sdk.Context, pagination *query.PageRequest) (sdk.Coins, *query.PageResponse, error)
 	IterateTotalSupply(ctx sdk.Context, cb func(sdk.Coin) bool)
 	GetDenomMetaData(ctx sdk.Context, denom string) (types.Metadata, bool)
+	HasDenomMetaData(ctx sdk.Context, denom string) bool
 	SetDenomMetaData(ctx sdk.Context, denomMetaData types.Metadata)
 	IterateAllDenomMetaData(ctx sdk.Context, cb func(types.Metadata) bool)
 
@@ -73,7 +74,6 @@ func (k BaseKeeper) GetPaginatedTotalSupply(ctx sdk.Context, pagination *query.P
 		supply = supply.Add(sdk.NewCoin(string(key), amount))
 		return nil
 	})
-
 	if err != nil {
 		return nil, nil, err
 	}
@@ -231,6 +231,13 @@ func (k BaseKeeper) GetDenomMetaData(ctx sdk.Context, denom string) (types.Metad
 	return metadata, true
 }
 
+// HasDenomMetaData checks if the denomination metadata exists in store.
+func (k BaseKeeper) HasDenomMetaData(ctx sdk.Context, denom string) bool {
+	store := ctx.KVStore(k.storeKey)
+	store = prefix.NewStore(store, types.DenomMetadataPrefix)
+	return store.Has([]byte(denom))
+}
+
 // GetAllDenomMetaData retrieves all denominations metadata
 func (k BaseKeeper) GetAllDenomMetaData(ctx sdk.Context) []types.Metadata {
 	denomMetaData := make([]types.Metadata, 0)

x/bank/keeper/keeper_test.go

@@ -1001,6 +1001,8 @@ func (suite *IntegrationTestSuite) TestSetDenomMetaData() {
 
 	actualMetadata, found := app.BankKeeper.GetDenomMetaData(ctx, metadata[1].Base)
 	suite.Require().True(found)
+	found = app.BankKeeper.HasDenomMetaData(ctx, metadata[1].Base)
+	suite.Require().True(found)
 	suite.Require().Equal(metadata[1].GetBase(), actualMetadata.GetBase())
 	suite.Require().Equal(metadata[1].GetDisplay(), actualMetadata.GetDisplay())
 	suite.Require().Equal(metadata[1].GetDescription(), actualMetadata.GetDescription())
@@ -1132,18 +1134,19 @@ func (suite *IntegrationTestSuite) TestBalanceTrackingEvents() {
 }
 
 func (suite *IntegrationTestSuite) getTestMetadata() []types.Metadata {
-	return []types.Metadata{{
-		Name:        "Cosmos Hub Atom",
-		Symbol:      "ATOM",
-		Description: "The native staking token of the Cosmos Hub.",
-		DenomUnits: []*types.DenomUnit{
-			{"uatom", uint32(0), []string{"microatom"}},
-			{"matom", uint32(3), []string{"milliatom"}},
-			{"atom", uint32(6), nil},
+	return []types.Metadata{
+		{
+			Name:        "Cosmos Hub Atom",
+			Symbol:      "ATOM",
+			Description: "The native staking token of the Cosmos Hub.",
+			DenomUnits: []*types.DenomUnit{
+				{"uatom", uint32(0), []string{"microatom"}},
+				{"matom", uint32(3), []string{"milliatom"}},
+				{"atom", uint32(6), nil},
+			},
+			Base:    "uatom",
+			Display: "atom",
 		},
-		Base:    "uatom",
-		Display: "atom",
-	},
 		{
 			Name:        "Token",
 			Symbol:      "TOKEN",