fix: x/authz allow insufficient funds error (backport #11252) (#11300)

* fix: x/authz allow insufficient funds error (#11252)

## Description

Allow insufficient funds error for authz simulation

Closes: #XXXX

---

### Author Checklist

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please add links to any relevant follow up issues.*

I have...

- [ ] included the correct [type prefix](https://github.com/commitizen/conventional-commit-types/blob/v3.0.0/index.json) in the PR title
- [ ] added `!` to the type prefix if API or client breaking change
- [ ] targeted the correct branch (see [PR Targeting](https://github.com/cosmos/cosmos-sdk/blob/master/CONTRIBUTING.md#pr-targeting))
- [ ] provided a link to the relevant issue or specification
- [ ] followed the guidelines for [building modules](https://github.com/cosmos/cosmos-sdk/blob/master/docs/building-modules)
- [ ] included the necessary unit and integration [tests](https://github.com/cosmos/cosmos-sdk/blob/master/CONTRIBUTING.md#testing)
- [ ] added a changelog entry to `CHANGELOG.md`
- [ ] included comments for [documenting Go code](https://blog.golang.org/godoc)
- [ ] updated the relevant documentation or specification
- [ ] reviewed "Files changed" and left comments if necessary
- [ ] confirmed all CI checks have passed

### Reviewers Checklist

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I have...

- [ ] confirmed the correct [type prefix](https://github.com/commitizen/conventional-commit-types/blob/v3.0.0/index.json) in the PR title
- [ ] confirmed `!` in the type prefix if API or client breaking change
- [ ] confirmed all author checklist items have been addressed
- [ ] reviewed state machine logic
- [ ] reviewed API design and naming
- [ ] reviewed documentation is accurate
- [ ] reviewed tests and test coverage
- [ ] manually tested (if applicable)

(cherry picked from commit a426780)

# Conflicts:
#	CHANGELOG.md
#	x/authz/simulation/operations.go

* resolve conflicts

* fix changelog

Co-authored-by: MD Aleem <72057206+aleem1314@users.noreply.github.com>
Co-authored-by: aleem1314 <aleem@vitwit.com>

CHANGELOG.md

@@ -46,6 +46,7 @@ Ref: https://keepachangelog.com/en/1.0.0/
 
 * (store) [\#11177](https://github.com/cosmos/cosmos-sdk/pull/11177) Update the prune `everything` strategy to store the last two heights.
 * (store) [\#11117](https://github.com/cosmos/cosmos-sdk/pull/11117) Fix data race in store trace component
+* (x/authz) [\#11252](https://github.com/cosmos/cosmos-sdk/pull/11252) Allow insufficient funds error for authz simulation
 
 ### Improvements
 

x/authz/simulation/operations.go

@@ -1,11 +1,8 @@
 package simulation
 
 import (
-	"fmt"
 	"math/rand"
 
-	"github.com/gogo/protobuf/proto"
-
 	"github.com/cosmos/cosmos-sdk/baseapp"
 	"github.com/cosmos/cosmos-sdk/codec"
 	cdctypes "github.com/cosmos/cosmos-sdk/codec/types"
@@ -227,6 +224,10 @@ func SimulateMsgExec(ak authz.AccountKeeper, bk authz.BankKeeper, k keeper.Keepe
 			return simtypes.NoOpMsg(authz.ModuleName, TypeMsgExec, "no grant found"), nil, nil
 		}
 
+		if targetGrant.Expiration.Before(ctx.BlockHeader().Time) {
+			return simtypes.NoOpMsg(authz.ModuleName, TypeMsgExec, "grant expired"), nil, nil
+		}
+
 		grantee, ok := simtypes.FindAccount(accs, granteeAddr)
 		if !ok {
 			return simtypes.NoOpMsg(authz.ModuleName, TypeMsgRevoke, "Account not found"), nil, sdkerrors.Wrapf(sdkerrors.ErrNotFound, "grantee account not found")
@@ -236,42 +237,43 @@ func SimulateMsgExec(ak authz.AccountKeeper, bk authz.BankKeeper, k keeper.Keepe
 			return simtypes.NoOpMsg(authz.ModuleName, TypeMsgRevoke, "Account not found"), nil, sdkerrors.Wrapf(sdkerrors.ErrNotFound, "granter account not found")
 		}
 
-		if targetGrant.Expiration.Before(ctx.BlockHeader().Time) {
-			return simtypes.NoOpMsg(authz.ModuleName, TypeMsgExec, "grant expired"), nil, nil
-		}
-
-		coins := sdk.NewCoins(sdk.NewCoin("stake", sdk.NewInt(int64(simtypes.RandIntBetween(r, 100, 1000000)))))
+		granterspendableCoins := bk.SpendableCoins(ctx, granterAddr)
+		coins := simtypes.RandSubsetCoins(r, granterspendableCoins)
 
 		// Check send_enabled status of each sent coin denom
 		if err := bk.IsSendEnabledCoins(ctx, coins...); err != nil {
 			return simtypes.NoOpMsg(authz.ModuleName, TypeMsgExec, err.Error()), nil, nil
 		}
 
-		if targetGrant.Authorization.TypeUrl == fmt.Sprintf("/%s", proto.MessageName(&banktype.SendAuthorization{})) {
-			sendAuthorization := targetGrant.GetAuthorization().(*banktype.SendAuthorization)
-			if sendAuthorization.SpendLimit.IsAllLT(coins) {
-				return simtypes.NoOpMsg(authz.ModuleName, TypeMsgExec, "over spend limit"), nil, nil
-			}
+		msg := []sdk.Msg{banktype.NewMsgSend(granterAddr, granteeAddr, coins)}
+		authorization := targetGrant.GetAuthorization()
+
+		sendAuth, ok := authorization.(*banktype.SendAuthorization)
+		if !ok {
+			return simtypes.NoOpMsg(authz.ModuleName, TypeMsgExec, "not a send authorization"), nil, nil
 		}
 
-		granterspendableCoins := bk.SpendableCoins(ctx, granterAddr)
-		if granterspendableCoins.IsAllLTE(coins) {
-			return simtypes.NoOpMsg(authz.ModuleName, TypeMsgExec, "insufficient funds"), nil, nil
+		_, err := sendAuth.Accept(ctx, msg[0])
+		if err != nil {
+			if sdkerrors.ErrInsufficientFunds.Is(err) {
+				return simtypes.NoOpMsg(authz.ModuleName, TypeMsgExec, err.Error()), nil, nil
+			} else {
+				return simtypes.NoOpMsg(authz.ModuleName, TypeMsgExec, err.Error()), nil, err
+			}
 		}
 
+		msgExec := authz.NewMsgExec(granteeAddr, msg)
 		granteeSpendableCoins := bk.SpendableCoins(ctx, granteeAddr)
 		fees, err := simtypes.RandomFees(r, ctx, granteeSpendableCoins)
 		if err != nil {
 			return simtypes.NoOpMsg(authz.ModuleName, TypeMsgExec, "fee error"), nil, err
 		}
 
-		msg := authz.NewMsgExec(granteeAddr, []sdk.Msg{banktype.NewMsgSend(granterAddr, granteeAddr, coins)})
 		txCfg := simappparams.MakeTestEncodingConfig().TxConfig
 		granteeAcc := ak.GetAccount(ctx, granteeAddr)
-
 		tx, err := helpers.GenTx(
 			txCfg,
-			[]sdk.Msg{&msg},
+			[]sdk.Msg{&msgExec},
 			fees,
 			helpers.DefaultGenTxGas,
 			chainID,
@@ -288,10 +290,10 @@ func SimulateMsgExec(ak authz.AccountKeeper, bk authz.BankKeeper, k keeper.Keepe
 			return simtypes.NoOpMsg(authz.ModuleName, TypeMsgExec, err.Error()), nil, err
 		}
 
-		err = msg.UnpackInterfaces(cdc)
+		err = msgExec.UnpackInterfaces(cdc)
 		if err != nil {
 			return simtypes.NoOpMsg(authz.ModuleName, TypeMsgExec, "unmarshal error"), nil, err
 		}
-		return simtypes.NewOperationMsg(&msg, true, "success", nil), nil, nil
+		return simtypes.NewOperationMsg(&msgExec, true, "success", nil), nil, nil
 	}
 }