feat: add extend cb to avoid unmarshal state twice for sim test (back…

…port: #15305) (#15324)

CHANGELOG.md

@@ -37,6 +37,10 @@ Ref: https://keepachangelog.com/en/1.0.0/
 
 ## [Unreleased]
 
+### Improvements
+
+* (simstestutil) [#15305](https://github.com/cosmos/cosmos-sdk/pull/15305) Add `AppStateFnWithExtendedCb` with callback function to extend rawState.
+
 ### Bug Fixes
 
 * [#15243](https://github.com/cosmos/cosmos-sdk/pull/15243) `LatestBlockResponse` & `BlockByHeightResponse` types' field `sdk_block` was incorrectly cast `proposer_address` bytes to validator operator address, now to consensus address

testutil/sims/state_helpers.go

@@ -34,6 +34,20 @@ const (
 // If a file is not given for the genesis or the sim params, it creates a randomized one.
 // genesisState is the default genesis state of the whole app.
 func AppStateFn(cdc codec.JSONCodec, simManager *module.SimulationManager, genesisState map[string]json.RawMessage) simtypes.AppStateFn {
+	return AppStateFnWithExtendedCb(cdc, simManager, genesisState, nil)
+}
+
+// AppStateFnWithExtendedCb returns the initial application state using a genesis or the simulation parameters.
+// It panics if the user provides files for both of them.
+// If a file is not given for the genesis or the sim params, it creates a randomized one.
+// genesisState is the default genesis state of the whole app.
+// cb is the callback function to extend rawState.
+func AppStateFnWithExtendedCb(
+	cdc codec.JSONCodec,
+	simManager *module.SimulationManager,
+	genesisState map[string]json.RawMessage,
+	cb func(rawState map[string]json.RawMessage),
+) simtypes.AppStateFn {
 	return func(
 		r *rand.Rand,
 		accs []simtypes.Account,
@@ -138,6 +152,11 @@ func AppStateFn(cdc codec.JSONCodec, simManager *module.SimulationManager, genes
 		rawState[stakingtypes.ModuleName] = cdc.MustMarshalJSON(stakingState)
 		rawState[banktypes.ModuleName] = cdc.MustMarshalJSON(bankState)
 
+		// extend state from callback function
+		if cb != nil {
+			cb(rawState)
+		}
+
 		// replace appstate
 		appState, err = json.Marshal(rawState)
 		if err != nil {

types/simulation/types.go

@@ -172,6 +172,11 @@ type AppStateFn func(r *rand.Rand, accs []Account, config Config) (
 	appState json.RawMessage, accounts []Account, chainId string, genesisTimestamp time.Time,
 )
 
+// AppStateFnWithExtendedCb returns the app state json bytes and the genesis accounts
+type AppStateFnWithExtendedCb func(r *rand.Rand, accs []Account, config Config) (
+	appState json.RawMessage, accounts []Account, chainId string, genesisTimestamp time.Time,
+)
+
 // RandomAccountFn returns a slice of n random simulation accounts
 type RandomAccountFn func(r *rand.Rand, n int) []Account