Add query for the total supply of a coin (#903)

* add bank supply query

* remove a local dev dependency

x/wasm/keeper/query_plugins.go

@@ -189,6 +189,16 @@ func BankQuerier(bankKeeper types.BankViewKeeper) func(ctx sdk.Context, request
 			}
 			return json.Marshal(res)
 		}
+		if request.Supply != nil {
+			coin := bankKeeper.GetSupply(ctx, request.Supply.Denom)
+			res := wasmvmtypes.SupplyResponse{
+				Amount: wasmvmtypes.Coin{
+					Denom:  coin.Denom,
+					Amount: coin.Amount.String(),
+				},
+			}
+			return json.Marshal(res)
+		}
 		return nil, wasmvmtypes.UnsupportedRequest{Kind: "unknown BankQuery variant"}
 	}
 }

x/wasm/keeper/query_plugins_test.go

@@ -511,10 +511,18 @@ func (m mockWasmQueryKeeper) IsPinnedCode(ctx sdk.Context, codeID uint64) bool {
 }
 
 type bankKeeperMock struct {
+	GetSupplyFn      func(ctx sdk.Context, denom string) sdk.Coin
 	GetBalanceFn     func(ctx sdk.Context, addr sdk.AccAddress, denom string) sdk.Coin
 	GetAllBalancesFn func(ctx sdk.Context, addr sdk.AccAddress) sdk.Coins
 }
 
+func (m bankKeeperMock) GetSupply(ctx sdk.Context, denom string) sdk.Coin {
+	if m.GetSupplyFn == nil {
+		panic("not expected to be called")
+	}
+	return m.GetSupplyFn(ctx, denom)
+}
+
 func (m bankKeeperMock) GetBalance(ctx sdk.Context, addr sdk.AccAddress, denom string) sdk.Coin {
 	if m.GetBalanceFn == nil {
 		panic("not expected to be called")

x/wasm/types/expected_keepers.go

@@ -17,6 +17,7 @@ import (
 type BankViewKeeper interface {
 	GetAllBalances(ctx sdk.Context, addr sdk.AccAddress) sdk.Coins
 	GetBalance(ctx sdk.Context, addr sdk.AccAddress, denom string) sdk.Coin
+	GetSupply(ctx sdk.Context, denom string) sdk.Coin
 }
 
 // Burner is a subset of the sdk bank keeper methods