Fix non-deterministic map iteration in fuzzer (#2069)

* This demonstrates that the state machine is non-deterministic if there
are more than two txs in a block.

* fix non-deterministic map iteration

* (squash this) fix build errors

* (squash this) iterate using range

cmd/gaia/app/sim_test.go

@@ -130,17 +130,13 @@ func TestFullGaiaSimulation(t *testing.T) {
 		},
 		numBlocks,
 		blockSize,
+		false,
 	)
 
 }
 
-// TODO: Make this not depend on Gaia or any of the modules,
-// and place it in random_simulation_test.go
-//
-// Test doesn't use `app.ExportAppStateAndValidators` as that panics with the following:
-// panic: Stored pool should not have been nil [recovered]
-//	panic: Stored pool should not have been nil
-// Change to `app.ExportAppStateAndValidators` once it is fixed
+// TODO: Make another test for the fuzzer itself, which just has noOp txs
+// and doesn't depend on gaia
 func TestAppStateDeterminism(t *testing.T) {
 	numTimesToRun := 5
 	appHashList := make([]json.RawMessage, numTimesToRun)
@@ -152,27 +148,39 @@ func TestAppStateDeterminism(t *testing.T) {
 		app := NewGaiaApp(logger, db, nil)
 
 		noOpInvariant := func(t *testing.T, baseapp *baseapp.BaseApp, log string) {}
-		noOpTestAndRunTx := func(t *testing.T, r *rand.Rand, app *baseapp.BaseApp, ctx sdk.Context,
-			privKeys []crypto.PrivKey, log string, event func(string),
-		) (action string, err sdk.Error) {
-			return "", nil
-		}
+		// noOpTestAndRunTx := func(t *testing.T, r *rand.Rand, app *baseapp.BaseApp, ctx sdk.Context,
+		// 	privKeys []crypto.PrivKey, log string, event func(string),
+		// ) (action string, err sdk.Error) {
+		// 	return "", nil
+		// }
 
 		// Run randomized simulation
 		simulation.SimulateFromSeed(
 			t, app.BaseApp, appStateFn, seed,
 			[]simulation.TestAndRunTx{
-				noOpTestAndRunTx,
+				banksim.TestAndRunSingleInputMsgSend(app.accountMapper),
+				govsim.SimulateMsgSubmitProposal(app.govKeeper, app.stakeKeeper),
+				govsim.SimulateMsgDeposit(app.govKeeper, app.stakeKeeper),
+				govsim.SimulateMsgVote(app.govKeeper, app.stakeKeeper),
+				stakesim.SimulateMsgCreateValidator(app.accountMapper, app.stakeKeeper),
+				stakesim.SimulateMsgEditValidator(app.stakeKeeper),
+				stakesim.SimulateMsgDelegate(app.accountMapper, app.stakeKeeper),
+				stakesim.SimulateMsgBeginUnbonding(app.accountMapper, app.stakeKeeper),
+				stakesim.SimulateMsgCompleteUnbonding(app.stakeKeeper),
+				stakesim.SimulateMsgBeginRedelegate(app.accountMapper, app.stakeKeeper),
+				stakesim.SimulateMsgCompleteRedelegate(app.stakeKeeper),
+				slashingsim.SimulateMsgUnrevoke(app.slashingKeeper),
 			},
 			[]simulation.RandSetup{},
 			[]simulation.Invariant{noOpInvariant},
-			0,
-			10,
+			20,
+			20,
+			true,
 		)
 		appHash := app.LastCommitID().Hash
 		appHashList[i] = appHash
 	}
 	for i := 1; i < numTimesToRun; i++ {
-		require.Equal(t, appHashList[0], appHashList[i])
+		require.Equal(t, appHashList[0], appHashList[i], "appHashes: %v", appHashList)
 	}
 }

x/bank/simulation/sim_test.go

@@ -42,5 +42,6 @@ func TestBankWithRandomMessages(t *testing.T) {
 			TotalCoinsInvariant(mapper, func() sdk.Coins { return mapp.TotalCoinsSupply }),
 		},
 		30, 30,
+		false,
 	)
 }

x/gov/simulation/sim_test.go

@@ -64,5 +64,6 @@ func TestGovWithRandomMessages(t *testing.T) {
 		}, []simulation.Invariant{
 			AllInvariants(),
 		}, 10, 100,
+		false,
 	)
 }

x/mock/simulation/random_simulate_blocks.go

@@ -4,6 +4,7 @@ import (
 	"encoding/json"
 	"fmt"
 	"math/rand"
+	"sort"
 	"testing"
 	"time"
 
@@ -20,17 +21,17 @@ import (
 // Simulate tests application by sending random messages.
 func Simulate(
 	t *testing.T, app *baseapp.BaseApp, appStateFn func(r *rand.Rand, keys []crypto.PrivKey, accs []sdk.AccAddress) json.RawMessage, ops []TestAndRunTx, setups []RandSetup,
-	invariants []Invariant, numBlocks int, blockSize int,
+	invariants []Invariant, numBlocks int, blockSize int, commit bool,
 ) {
 	time := time.Now().UnixNano()
-	SimulateFromSeed(t, app, appStateFn, time, ops, setups, invariants, numBlocks, blockSize)
+	SimulateFromSeed(t, app, appStateFn, time, ops, setups, invariants, numBlocks, blockSize, commit)
 }
 
 // SimulateFromSeed tests an application by running the provided
 // operations, testing the provided invariants, but using the provided seed.
 func SimulateFromSeed(
 	t *testing.T, app *baseapp.BaseApp, appStateFn func(r *rand.Rand, keys []crypto.PrivKey, accs []sdk.AccAddress) json.RawMessage, seed int64, ops []TestAndRunTx, setups []RandSetup,
-	invariants []Invariant, numBlocks int, blockSize int,
+	invariants []Invariant, numBlocks int, blockSize int, commit bool,
 ) {
 	log := fmt.Sprintf("Starting SimulateFromSeed with randomness created with seed %d", int(seed))
 	fmt.Printf("%s\n", log)
@@ -104,6 +105,9 @@ func SimulateFromSeed(
 		}
 
 		res := app.EndBlock(abci.RequestEndBlock{})
+		if commit {
+			app.Commit()
+		}
 		header.Height++
 		header.Time = header.Time.Add(time.Duration(minTimePerBlock) * time.Second).Add(time.Duration(int64(r.Intn(int(timeDiff)))) * time.Second)
 
@@ -123,6 +127,17 @@ func SimulateFromSeed(
 	DisplayEvents(events)
 }
 
+func getKeys(validators map[string]mockValidator) []string {
+	keys := make([]string, len(validators))
+	i := 0
+	for key := range validators {
+		keys[i] = key
+		i++
+	}
+	sort.Strings(keys)
+	return keys
+}
+
 // RandomRequestBeginBlock generates a list of signing validators according to the provided list of validators, signing fraction, and evidence fraction
 func RandomRequestBeginBlock(t *testing.T, r *rand.Rand, validators map[string]mockValidator, livenessTransitions TransitionMatrix, evidenceFraction float64,
 	pastTimes []time.Time, event func(string), header abci.Header, log string) abci.RequestBeginBlock {
@@ -131,7 +146,9 @@ func RandomRequestBeginBlock(t *testing.T, r *rand.Rand, validators map[string]m
 	}
 	signingValidators := make([]abci.SigningValidator, len(validators))
 	i := 0
-	for _, mVal := range validators {
+
+	for _, key := range getKeys(validators) {
+		mVal := validators[key]
 		mVal.livenessState = livenessTransitions.NextState(r, mVal.livenessState)
 		signed := true
 

x/stake/simulation/sim_test.go

@@ -57,5 +57,6 @@ func TestStakeWithRandomMessages(t *testing.T) {
 		}, []simulation.Invariant{
 			AllInvariants(coinKeeper, stakeKeeper, mapp.AccountMapper),
 		}, 10, 100,
+		false,
 	)
 }