Prettier GlobalFee fees errors (#809)

* prettier fees failure output

* pretty fee subset

* no coins at all error message

* Prettier slice output. Show coins needed for fee

x/globalfee/ante/fee.go

@@ -88,7 +88,7 @@ func (mfd FeeDecorator) AnteHandle(ctx sdk.Context, tx sdk.Tx, simulate bool, ne
 	// if feeCoinsNoZeroDenom=[], DenomsSubsetOf returns true
 	// if feeCoinsNoZeroDenom is not empty, but nonZeroCoinFeesReq empty, return false
 	if !feeCoinsNonZeroDenom.DenomsSubsetOf(nonZeroCoinFeesReq) {
-		return ctx, errorsmod.Wrapf(sdkerrors.ErrInsufficientFee, "fee is not a subset of required fees; got %s, required: %s", feeCoins, combinedFeeRequirement)
+		return ctx, errorsmod.Wrapf(sdkerrors.ErrInsufficientFee, "this fee denom is not accepted; got %s, one is required: %s", feeCoins, PrettyPrint(combinedFeeRequirement))
 	}
 
 	// Accept zero fee transactions only if both of the following statements are true:
@@ -125,7 +125,16 @@ func (mfd FeeDecorator) AnteHandle(ctx sdk.Context, tx sdk.Tx, simulate bool, ne
 		// because when nonZeroCoinFeesReq empty, and DenomsSubsetOf check passed,
 		// the tx should already passed before)
 		if !feeCoinsNonZeroDenom.IsAnyGTE(nonZeroCoinFeesReq) {
-			return ctx, errorsmod.Wrapf(sdkerrors.ErrInsufficientFee, "insufficient fees; got: %s required: %s", feeCoins, combinedFeeRequirement)
+			if len(feeCoins) == 0 {
+				return ctx, errorsmod.Wrapf(sdkerrors.ErrInsufficientFee, "no fees were specified; one fee must be provided %s", PrettyPrint(combinedFeeRequirement))
+			}
+
+			feeDiff := combinedFeeRequirement
+			for _, c := range feeCoins {
+				feeDiff = feeDiff.Sub(c)
+			}
+
+			return ctx, errorsmod.Wrapf(sdkerrors.ErrInsufficientFee, "insufficient fees; only got: %s. number of coins needed: %s. one is required: %s. ", feeCoins, feeDiff, PrettyPrint(combinedFeeRequirement))
 		}
 	}
 

x/globalfee/ante/fee_utils.go

@@ -1,6 +1,9 @@
 package ante
 
 import (
+	"encoding/json"
+	"fmt"
+
 	sdk "github.com/cosmos/cosmos-sdk/types"
 )
 
@@ -19,6 +22,21 @@ func ContainZeroCoins(coins sdk.Coins) bool {
 	return false
 }
 
+// PrettyPrint returns a pretty printed representation of the given coins.
+func PrettyPrint(coins sdk.Coins) string {
+	arr := make([]string, len(coins))
+	for idx, coin := range coins {
+		arr[idx] = fmt.Sprintf("%s%s", coin.Amount.String(), coin.Denom)
+	}
+
+	bz, err := json.MarshalIndent(arr, "", "  ")
+	if err != nil {
+		return ""
+	}
+
+	return string(bz)
+}
+
 // CombinedFeeRequirement returns the global fee and min_gas_price combined and sorted.
 // Both globalFees and minGasPrices must be valid, but CombinedFeeRequirement
 // does not validate them, so it may return 0denom.