12 changed files with 348 additions and 27 deletions
--- a/.github/workflows/test.yml
+++ b/.github/workflows/test.yml
@ -117,4 +117,84 @@ jobs:
      - name: Test e2e
        run: |
          make test-integration
+        if: env.GIT_DIFF
+
+  test-sim-nondeterminism:
+    runs-on: ubuntu-latest
+    timeout-minutes: 15
+    steps:
+      - uses: actions/setup-go@v3
+        with:
+          go-version: 1.17
+          check-latest: true
+      - uses: actions/checkout@v3
+      - uses: technote-space/get-diff-action@v6.0.1
+        with:
+          PATTERNS: |
+            **/**.go
+            go.mod
+            go.sum
+      - name: Test x/evm simulation nondeterminism
+        run: |
+          make test-sim-nondeterminism
+        if: env.GIT_DIFF
+
+  test-sim-random-genesis-fast:
+    runs-on: ubuntu-latest
+    timeout-minutes: 15
+    steps:
+      - uses: actions/setup-go@v3
+        with:
+          go-version: 1.17
+          check-latest: true
+      - uses: actions/checkout@v3
+      - uses: technote-space/get-diff-action@v6.0.1
+        with:
+          PATTERNS: |
+            **/**.go
+            go.mod
+            go.sum
+      - name: Test x/evm simulation with random genesis 
+        run: |
+          make test-sim-random-genesis-fast
+        if: env.GIT_DIFF
+
+  test-sim-import-export:
+    runs-on: ubuntu-latest
+    timeout-minutes: 15
+    steps:
+      - uses: actions/setup-go@v3
+        with:
+          go-version: 1.17
+          check-latest: true
+      - uses: actions/checkout@v3
+      - uses: technote-space/get-diff-action@v6.0.1
+        with:
+          PATTERNS: |
+            **/**.go
+            go.mod
+            go.sum
+      - name: Test x/evm simulation import and export
+        run: |
+          make test-sim-import-export
+        if: env.GIT_DIFF
+
+  test-sim-after-import:
+    runs-on: ubuntu-latest
+    timeout-minutes: 15
+    steps:
+      - uses: actions/setup-go@v3
+        with:
+          go-version: 1.17
+          check-latest: true
+      - uses: actions/checkout@v3
+      - uses: technote-space/get-diff-action@v6.0.1
+        with:
+          PATTERNS: |
+            **/**.go
+            go.mod
+            go.sum
+      - name: Test x/evm simulation after import
+        run: |
+          make test-sim-after-import
        if: env.GIT_DIFF
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@ -47,6 +47,10 @@ Ref: https://keepachangelog.com/en/1.0.0/
  * Move `rpc/ethereum/backend` -> `rpc/backend`
  * Move `rpc/ethereum/namespaces` -> `rpc/namespaces/ethereum`

+### Improvements
+
+* (ci, evm) [tharsis#1063](https://github.com/tharsis/ethermint/pull/1063) Run simulations on CI.
+
 ### Bug Fixes

 * (rpc) [tharsis#1059](https://github.com/tharsis/ethermint/pull/1059) Remove unnecessary event filtering logic on the `eth_baseFee` JSON-RPC endpoint.
--- a/4
+++ b/4
@ -201,7 +201,7 @@ RUNSIM         = $(TOOLS_DESTDIR)/runsim
 runsim: $(RUNSIM)
 $(RUNSIM):
 	@echo "Installing runsim..."
-	@(cd /tmp && ${GO_MOD} go get github.com/cosmos/tools/cmd/runsim@master)
+	@(cd /tmp && ${GO_MOD} go install github.com/cosmos/tools/cmd/runsim@master)

 statik: $(STATIK)
 $(STATIK):
@ -343,7 +343,7 @@ test-sim-nondeterminism:
 		-NumBlocks=100 -BlockSize=200 -Commit=true -Period=0 -v -timeout 24h

 test-sim-random-genesis-fast:
-	@echo "Running custom genesis simulation..."
+	@echo "Running random genesis simulation..."
 	@go test -mod=readonly $(SIMAPP) -run TestFullAppSimulation \
 		-Enabled=true -NumBlocks=100 -BlockSize=200 -Commit=true -Seed=99 -Period=5 -v -timeout 24h

--- a/app/utils.go
+++ b/app/utils.go
@ -108,7 +108,7 @@ func RandomAccounts(r *rand.Rand, n int) []simtypes.Account {

 		prv := secp256k1.GenPrivKeyFromSecret(privkeySeed)
 		ethPrv := &ethsecp256k1.PrivKey{}
-		_ = ethPrv.UnmarshalAmino(prv.Bytes())
+		_ = ethPrv.UnmarshalAmino(prv.Bytes()) // UnmarshalAmino simply copies the bytes and assigns them to ethPrv.Key
 		accs[i].PrivKey = ethPrv
 		accs[i].PubKey = accs[i].PrivKey.PubKey()
 		accs[i].Address = sdk.AccAddress(accs[i].PubKey.Address())
--- a/app/utils_test.go
+++ b/app/utils_test.go
@ -1,7 +1,9 @@
 package app

 import (
+	"encoding/json"
 	"math/rand"
+	"os"
 	"testing"

 	"github.com/stretchr/testify/require"
@ -11,7 +13,10 @@ import (
 	authkeeper "github.com/cosmos/cosmos-sdk/x/auth/keeper"
 	authtypes "github.com/cosmos/cosmos-sdk/x/auth/types"
 	paramstypes "github.com/cosmos/cosmos-sdk/x/params/types"
+	stakingtypes "github.com/cosmos/cosmos-sdk/x/staking/types"
+	evmtypes "github.com/tharsis/ethermint/x/evm/types"

+	"github.com/tharsis/ethermint/crypto/ethsecp256k1"
 	ethermint "github.com/tharsis/ethermint/types"

 	"github.com/cosmos/cosmos-sdk/simapp"
@ -53,3 +58,54 @@ func TestRandomGenesisAccounts(t *testing.T) {
 		require.True(t, ok)
 	}
 }
+
+func TestStateFn(t *testing.T) {
+	config, db, dir, logger, skip, err := simapp.SetupSimulation("leveldb-app-sim", "Simulation")
+	if skip {
+		t.Skip("skipping AppStateFn testing")
+	}
+	require.NoError(t, err, "simulation setup failed")
+
+	config.ChainID = SimAppChainID
+	config.Commit = true
+
+	defer func() {
+		db.Close()
+		require.NoError(t, os.RemoveAll(dir))
+	}()
+
+	app := NewEthermintApp(logger, db, nil, true, map[int64]bool{}, DefaultNodeHome, simapp.FlagPeriodValue, MakeEncodingConfig(), simapp.EmptyAppOptions{}, fauxMerkleModeOpt)
+	require.Equal(t, appName, app.Name())
+
+	appStateFn := StateFn(app.AppCodec(), app.SimulationManager())
+	r := rand.New(rand.NewSource(seed))
+	accounts := RandomAccounts(r, rand.Intn(maxTestingAccounts))
+	appState, _, _, _ := appStateFn(r, accounts, config)
+
+	rawState := make(map[string]json.RawMessage)
+	err = json.Unmarshal(appState, &rawState)
+	require.NoError(t, err)
+
+	stakingStateBz, ok := rawState[stakingtypes.ModuleName]
+	require.True(t, ok)
+
+	stakingState := new(stakingtypes.GenesisState)
+	app.AppCodec().MustUnmarshalJSON(stakingStateBz, stakingState)
+	bondDenom := stakingState.Params.BondDenom
+
+	evmStateBz, ok := rawState[evmtypes.ModuleName]
+	require.True(t, ok)
+
+	evmState := new(evmtypes.GenesisState)
+	app.AppCodec().MustUnmarshalJSON(evmStateBz, evmState)
+	require.Equal(t, bondDenom, evmState.Params.EvmDenom)
+}
+
+func TestRandomAccounts(t *testing.T) {
+	r := rand.New(rand.NewSource(seed))
+	accounts := RandomAccounts(r, rand.Intn(maxTestingAccounts))
+	for _, acc := range accounts {
+		_, ok := acc.PrivKey.(*ethsecp256k1.PrivKey)
+		require.True(t, ok)
+	}
+}
--- a/x/evm/simulation/decoder.go
+++ b/x/evm/simulation/decoder.go
@ -10,18 +10,18 @@ import (
 )

 // NewDecodeStore returns a decoder function closure that unmarshals the KVPair's
-// Value to the corresponding evm type.
+// value to the corresponding EVM type.
 func NewDecodeStore() func(kvA, kvB kv.Pair) string {
 	return func(kvA, kvB kv.Pair) string {
 		switch {
 		case bytes.Equal(kvA.Key[:1], types.KeyPrefixStorage):
-			storageHashA := common.BytesToHash(kvA.Value).Hex()
-			storageHashB := common.BytesToHash(kvB.Value).Hex()
+			storageA := common.BytesToHash(kvA.Value).Hex()
+			storageB := common.BytesToHash(kvB.Value).Hex()

-			return fmt.Sprintf("%v\n%v", storageHashA, storageHashB)
+			return fmt.Sprintf("%v\n%v", storageA, storageB)
 		case bytes.Equal(kvA.Key[:1], types.KeyPrefixCode):
-			codeHashA := common.BytesToHash(kvA.Value).Hex()
-			codeHashB := common.BytesToHash(kvB.Value).Hex()
+			codeHashA := common.Bytes2Hex(kvA.Value)
+			codeHashB := common.Bytes2Hex(kvB.Value)

 			return fmt.Sprintf("%v\n%v", codeHashA, codeHashB)
 		default:
--- a/x/evm/simulation/decoder_test.go
+++ b/x/evm/simulation/decoder_test.go
@ -0,0 +1,47 @@
+package simulation
+
+import (
+	"fmt"
+	"testing"
+
+	"github.com/stretchr/testify/require"
+
+	"github.com/cosmos/cosmos-sdk/types/kv"
+	"github.com/ethereum/go-ethereum/common"
+	"github.com/tharsis/ethermint/x/evm/types"
+)
+
+// TestDecodeStore tests that evm simulation decoder decodes the key value pairs as expected.
+func TestDecodeStore(t *testing.T) {
+	dec := NewDecodeStore()
+
+	hash := common.BytesToHash([]byte("hash"))
+	code := common.Bytes2Hex([]byte{1, 2, 3})
+
+	kvPairs := kv.Pairs{
+		Pairs: []kv.Pair{
+			{Key: types.KeyPrefixCode, Value: common.FromHex(code)},
+			{Key: types.KeyPrefixStorage, Value: hash.Bytes()},
+		},
+	}
+
+	tests := []struct {
+		name        string
+		expectedLog string
+	}{
+		{"Code", fmt.Sprintf("%v\n%v", code, code)},
+		{"Storage", fmt.Sprintf("%v\n%v", hash, hash)},
+		{"other", ""},
+	}
+	for i, tt := range tests {
+		i, tt := i, tt
+		t.Run(tt.name, func(t *testing.T) {
+			switch i {
+			case len(tests) - 1:
+				require.Panics(t, func() { dec(kvPairs.Pairs[i], kvPairs.Pairs[i]) }, tt.name)
+			default:
+				require.Equal(t, tt.expectedLog, dec(kvPairs.Pairs[i], kvPairs.Pairs[i]), tt.name)
+			}
+		})
+	}
+}
--- a/x/evm/simulation/genesis.go
+++ b/x/evm/simulation/genesis.go
@ -10,18 +10,44 @@ import (
 	"github.com/tharsis/ethermint/x/evm/types"
 )

-// GenExtraEIPs randomly generates specific extra eips or not.
-func genExtraEIPs(r *rand.Rand) []int64 {
+const (
+	extraEIPsKey = "extra_eips"
+)
+
+// GenExtraEIPs defines a set of extra EIPs with 50% probability
+func GenExtraEIPs(r *rand.Rand) []int64 {
 	var extraEIPs []int64
-	if r.Uint32()%2 == 0 {
+	// 50% chance of having extra EIPs
+	if r.Intn(2) == 0 {
 		extraEIPs = []int64{1344, 1884, 2200, 2929, 3198, 3529}
 	}
 	return extraEIPs
 }

-// RandomizedGenState generates a random GenesisState for nft
+// GenEnableCreate enables the EnableCreate param with 80% probability
+func GenEnableCreate(r *rand.Rand) bool {
+	// 80% chance of enabling create contract
+	enableCreate := r.Intn(100) < 80
+	return enableCreate
+}
+
+// GenEnableCall enables the EnableCall param with 80% probability
+func GenEnableCall(r *rand.Rand) bool {
+	// 80% chance of enabling evm account transfer and calling contract
+	enableCall := r.Intn(100) < 80
+	return enableCall
+}
+
+// RandomizedGenState generates a random GenesisState for the EVM module
 func RandomizedGenState(simState *module.SimulationState) {
-	extraEIPs := genExtraEIPs(simState.Rand)
+	// evm params
+	var extraEIPs []int64
+
+	simState.AppParams.GetOrGenerate(
+		simState.Cdc, extraEIPsKey, &extraEIPs, simState.Rand,
+		func(r *rand.Rand) { extraEIPs = GenExtraEIPs(r) },
+	)
+
 	params := types.NewParams(types.DefaultEVMDenom, true, true, types.DefaultChainConfig(), extraEIPs...)
 	evmGenesis := types.NewGenesisState(params, []types.GenesisAccount{})

--- a/x/evm/simulation/genesis_test.go
+++ b/x/evm/simulation/genesis_test.go
@ -0,0 +1,50 @@
+package simulation_test
+
+import (
+	"encoding/json"
+	"math/rand"
+	"testing"
+
+	"github.com/stretchr/testify/require"
+
+	"github.com/cosmos/cosmos-sdk/codec"
+	codectypes "github.com/cosmos/cosmos-sdk/codec/types"
+	"github.com/cosmos/cosmos-sdk/types/module"
+	simtypes "github.com/cosmos/cosmos-sdk/types/simulation"
+	"github.com/tharsis/ethermint/x/evm/simulation"
+	"github.com/tharsis/ethermint/x/evm/types"
+)
+
+// TestRandomizedGenState tests the normal scenario of applying RandomizedGenState.
+// Abonormal scenarios are not tested here.
+func TestRandomizedGenState(t *testing.T) {
+	registry := codectypes.NewInterfaceRegistry()
+	types.RegisterInterfaces(registry)
+	cdc := codec.NewProtoCodec(registry)
+
+	s := rand.NewSource(1)
+	r := rand.New(s)
+
+	simState := module.SimulationState{
+		AppParams:    make(simtypes.AppParams),
+		Cdc:          cdc,
+		Rand:         r,
+		NumBonded:    3,
+		Accounts:     simtypes.RandomAccounts(r, 3),
+		InitialStake: 1000,
+		GenState:     make(map[string]json.RawMessage),
+	}
+
+	simulation.RandomizedGenState(&simState)
+
+	var evmGenesis types.GenesisState
+	simState.Cdc.MustUnmarshalJSON(simState.GenState[types.ModuleName], &evmGenesis)
+
+	require.Equal(t, true, evmGenesis.Params.GetEnableCreate())
+	require.Equal(t, true, evmGenesis.Params.GetEnableCall())
+	require.Equal(t, types.DefaultEVMDenom, evmGenesis.Params.GetEvmDenom())
+	require.Equal(t, simulation.GenExtraEIPs(r), evmGenesis.Params.GetExtraEIPs())
+	require.Equal(t, types.DefaultChainConfig(), evmGenesis.Params.GetChainConfig())
+
+	require.Equal(t, len(evmGenesis.Accounts), 0)
+}
--- a/x/evm/simulation/operations.go
+++ b/x/evm/simulation/operations.go
@ -25,7 +25,6 @@ import (
 	"github.com/cosmos/cosmos-sdk/x/auth/signing"
 	"github.com/ethereum/go-ethereum/crypto"
 	"github.com/tharsis/ethermint/encoding"
-	"github.com/tharsis/ethermint/server/config"
 	"github.com/tharsis/ethermint/tests"
 	"github.com/tharsis/ethermint/x/evm/keeper"
 	"github.com/tharsis/ethermint/x/evm/types"
@ -203,10 +202,12 @@ func SimulateEthTx(

 // CreateRandomValidEthTx create the ethereum tx with valid random values
 func CreateRandomValidEthTx(ctx *simulateContext, from, to *common.Address, amount *big.Int, data *hexutil.Bytes) (ethTx *types.MsgEthereumTx, err error) {
-	estimateGas, err := EstimateGas(ctx, from, to, data)
+	gasCap := ctx.rand.Uint64()
+	estimateGas, err := EstimateGas(ctx, from, to, data, gasCap)
 	if err != nil {
 		return nil, err
 	}
+	// we suppose that gasLimit should be larger than estimateGas to ensure tx validity
 	gasLimit := estimateGas + uint64(ctx.rand.Intn(int(sdktx.MaxGasWanted-estimateGas)))
 	ethChainID := ctx.keeper.ChainID()
 	chainConfig := ctx.keeper.GetParams(ctx.context).ChainConfig.EthereumConfig(ethChainID)
@ -216,7 +217,7 @@ func CreateRandomValidEthTx(ctx *simulateContext, from, to *common.Address, amou
 	nonce := ctx.keeper.GetNonce(ctx.context, *from)

 	if amount == nil {
-		amount, err = RandomTransferableAmount(ctx, *from, gasLimit, gasFeeCap)
+		amount, err = RandomTransferableAmount(ctx, *from, estimateGas, gasFeeCap)
 		if err != nil {
 			return nil, err
 		}
@ -228,7 +229,7 @@ func CreateRandomValidEthTx(ctx *simulateContext, from, to *common.Address, amou
 }

 // EstimateGas estimates the gas used by quering the keeper.
-func EstimateGas(ctx *simulateContext, from, to *common.Address, data *hexutil.Bytes) (gas uint64, err error) {
+func EstimateGas(ctx *simulateContext, from, to *common.Address, data *hexutil.Bytes, gasCap uint64) (gas uint64, err error) {
 	args, err := json.Marshal(&types.TransactionArgs{To: to, From: from, Data: data})
 	if err != nil {
 		return 0, err
@ -236,7 +237,7 @@ func EstimateGas(ctx *simulateContext, from, to *common.Address, data *hexutil.B

 	res, err := ctx.keeper.EstimateGas(sdk.WrapSDKContext(ctx.context), &types.EthCallRequest{
 		Args:   args,
-		GasCap: config.DefaultGasCap,
+		GasCap: gasCap,
 	})
 	if err != nil {
 		return 0, err
@ -246,9 +247,9 @@ func EstimateGas(ctx *simulateContext, from, to *common.Address, data *hexutil.B

 // RandomTransferableAmount generates a random valid transferable amount.
 // Transferable amount is between the range [0, spendable), spendable = balance - gasFeeCap * GasLimit.
-func RandomTransferableAmount(ctx *simulateContext, address common.Address, gasLimit uint64, gasFeeCap *big.Int) (amount *big.Int, err error) {
+func RandomTransferableAmount(ctx *simulateContext, address common.Address, estimateGas uint64, gasFeeCap *big.Int) (amount *big.Int, err error) {
 	balance := ctx.keeper.GetBalance(ctx.context, address)
-	feeLimit := new(big.Int).Mul(gasFeeCap, big.NewInt(int64(gasLimit)))
+	feeLimit := new(big.Int).Mul(gasFeeCap, big.NewInt(int64(estimateGas)))
 	if (feeLimit.Cmp(balance)) > 0 {
 		return nil, ErrNoEnoughBalance
 	}
--- a/x/evm/simulation/params.go
+++ b/x/evm/simulation/params.go
@ -6,22 +6,35 @@ import (
 	"fmt"
 	"math/rand"

+	amino "github.com/cosmos/cosmos-sdk/codec"
 	simtypes "github.com/cosmos/cosmos-sdk/types/simulation"
 	"github.com/cosmos/cosmos-sdk/x/simulation"
 	"github.com/tharsis/ethermint/x/evm/types"
 )

-const (
-	keyExtraEIPs = "ExtraEIPs"
-)
-
 // ParamChanges defines the parameters that can be modified by param change proposals
 // on the simulation.
 func ParamChanges(r *rand.Rand) []simtypes.ParamChange {
 	return []simtypes.ParamChange{
-		simulation.NewSimParamChange(types.ModuleName, keyExtraEIPs,
+		simulation.NewSimParamChange(types.ModuleName, string(types.ParamStoreKeyExtraEIPs),
 			func(r *rand.Rand) string {
-				return fmt.Sprintf("\"%d\"", genExtraEIPs(r))
+				extraEIPs := GenExtraEIPs(r)
+				amino := amino.NewLegacyAmino()
+				bz, err := amino.MarshalJSON(extraEIPs)
+				if err != nil {
+					panic(err)
+				}
+				return string(bz)
+			},
+		),
+		simulation.NewSimParamChange(types.ModuleName, string(types.ParamStoreKeyEnableCreate),
+			func(r *rand.Rand) string {
+				return fmt.Sprintf("%v", GenEnableCreate(r))
+			},
+		),
+		simulation.NewSimParamChange(types.ModuleName, string(types.ParamStoreKeyEnableCall),
+			func(r *rand.Rand) string {
+				return fmt.Sprintf("%v", GenEnableCall(r))
 			},
 		),
 	}
--- a/x/evm/simulation/params_test.go
+++ b/x/evm/simulation/params_test.go
@ -0,0 +1,44 @@
+package simulation_test
+
+import (
+	"encoding/json"
+	"fmt"
+	"math/rand"
+	"testing"
+
+	"github.com/stretchr/testify/require"
+
+	"github.com/tharsis/ethermint/x/evm/simulation"
+)
+
+// TestParamChanges tests the paramChanges are generated as expected.
+func TestParamChanges(t *testing.T) {
+	s := rand.NewSource(1)
+	r := rand.New(s)
+
+	extraEIPs := simulation.GenExtraEIPs(r)
+	bz, err := json.Marshal(extraEIPs)
+	require.NoError(t, err)
+
+	expected := []struct {
+		composedKey string
+		key         string
+		simValue    string
+		subspace    string
+	}{
+		{"evm/EnableExtraEIPs", "EnableExtraEIPs", string(bz), "evm"},
+		{"evm/EnableCreate", "EnableCreate", fmt.Sprintf("%v", simulation.GenEnableCreate(r)), "evm"},
+		{"evm/EnableCall", "EnableCall", fmt.Sprintf("%v", simulation.GenEnableCall(r)), "evm"},
+	}
+
+	paramChanges := simulation.ParamChanges(r)
+
+	require.Len(t, paramChanges, 3)
+
+	for i, p := range paramChanges {
+		require.Equal(t, expected[i].composedKey, p.ComposedKey())
+		require.Equal(t, expected[i].key, p.Key())
+		require.Equal(t, expected[i].simValue, p.SimValue()(r))
+		require.Equal(t, expected[i].subspace, p.Subspace())
+	}
+}