simulation: Make validator choice use validator set

This also had to change the default seed, since with the previous one it
actually got into a state where there were no validators left bonded, lol.

This also changes Unbond msgs from failing with almost 100% probability to now
only failing with 33% probability.
Thus more of the state machine is getting tested!

Makefile

@@ -169,7 +169,7 @@ test_sim_gaia_nondeterminism:
 
 test_sim_gaia_fast:
 	@echo "Running quick Gaia simulation. This may take several minutes..."
-	@go test ./cmd/gaia/app -run TestFullGaiaSimulation -SimulationEnabled=true -SimulationNumBlocks=500 -SimulationBlockSize=200 -SimulationCommit=true -SimulationSeed=9 -v -timeout 24h
+	@go test ./cmd/gaia/app -run TestFullGaiaSimulation -SimulationEnabled=true -SimulationNumBlocks=500 -SimulationBlockSize=200 -SimulationCommit=true -SimulationSeed=10 -v -timeout 24h
 
 test_sim_gaia_multi_seed:
 	@echo "Running multi-seed Gaia simulation. This may take awhile!"

x/mock/simulation/util.go

@@ -2,6 +2,7 @@ package simulation
 
 import (
 	"fmt"
+	"math/big"
 	"math/rand"
 	"os"
 	"sort"
@@ -71,6 +72,12 @@ func RandomAmount(r *rand.Rand, max sdk.Int) sdk.Int {
 	return sdk.NewInt(int64(r.Intn(int(max.Int64()))))
 }
 
+// RandomDecAmount generates a random decimal amount
+func RandomDecAmount(r *rand.Rand, max sdk.Dec) sdk.Dec {
+	randInt := big.NewInt(0).Rand(r, max.Int)
+	return sdk.NewDecFromBigIntWithPrec(randInt, sdk.Precision)
+}
+
 // RandomAccounts generates n random accounts
 func RandomAccounts(r *rand.Rand, n int) []Account {
 	accs := make([]Account, n)

x/stake/keeper/test_common.go

@@ -3,6 +3,7 @@ package keeper
 import (
 	"bytes"
 	"encoding/hex"
+	"math/rand"
 	"strconv"
 	"testing"
 
@@ -215,3 +216,17 @@ func validatorByPowerIndexExists(k Keeper, ctx sdk.Context, power []byte) bool {
 	store := ctx.KVStore(k.storeKey)
 	return store.Has(power)
 }
+
+// RandomValidator returns a random validator given access to the keeper and ctx
+func RandomValidator(r *rand.Rand, keeper Keeper, ctx sdk.Context) types.Validator {
+	vals := keeper.GetAllValidators(ctx)
+	i := r.Intn(len(vals))
+	return vals[i]
+}
+
+// RandomBondedValidator returns a random bonded validator given access to the keeper and ctx
+func RandomBondedValidator(r *rand.Rand, keeper Keeper, ctx sdk.Context) types.Validator {
+	vals := keeper.GetBondedValidatorsByPower(ctx)
+	i := r.Intn(len(vals))
+	return vals[i]
+}

x/stake/simulation/msgs.go

@@ -10,6 +10,7 @@ import (
 	"github.com/cosmos/cosmos-sdk/x/mock"
 	"github.com/cosmos/cosmos-sdk/x/mock/simulation"
 	"github.com/cosmos/cosmos-sdk/x/stake"
+	"github.com/cosmos/cosmos-sdk/x/stake/keeper"
 	abci "github.com/tendermint/tendermint/abci/types"
 )
 
@@ -87,8 +88,8 @@ func SimulateMsgEditValidator(k stake.Keeper) simulation.Operation {
 		maxCommission := sdk.NewInt(10)
 		newCommissionRate := sdk.NewDecWithPrec(simulation.RandomAmount(r, maxCommission).Int64(), 1)
 
-		acc := simulation.RandomAcc(r, accs)
-		address := sdk.ValAddress(acc.Address)
+		val := keeper.RandomValidator(r, k, ctx)
+		address := val.GetOperator()
 		msg := stake.MsgEditValidator{
 			Description:    description,
 			ValidatorAddr:  address,
@@ -118,8 +119,8 @@ func SimulateMsgDelegate(m auth.AccountKeeper, k stake.Keeper) simulation.Operat
 		action string, fOp []simulation.FutureOperation, err error) {
 
 		denom := k.GetParams(ctx).BondDenom
-		validatorAcc := simulation.RandomAcc(r, accs)
-		validatorAddress := sdk.ValAddress(validatorAcc.Address)
+		val := keeper.RandomValidator(r, k, ctx)
+		validatorAddress := val.GetOperator()
 		delegatorAcc := simulation.RandomAcc(r, accs)
 		delegatorAddress := delegatorAcc.Address
 		amount := m.GetAccount(ctx, delegatorAddress).GetCoins().AmountOf(denom)
@@ -155,25 +156,26 @@ func SimulateMsgBeginUnbonding(m auth.AccountKeeper, k stake.Keeper) simulation.
 		accs []simulation.Account, event func(string)) (
 		action string, fOp []simulation.FutureOperation, err error) {
 
-		denom := k.GetParams(ctx).BondDenom
-		validatorAcc := simulation.RandomAcc(r, accs)
-		validatorAddress := sdk.ValAddress(validatorAcc.Address)
 		delegatorAcc := simulation.RandomAcc(r, accs)
 		delegatorAddress := delegatorAcc.Address
-		amount := m.GetAccount(ctx, delegatorAddress).GetCoins().AmountOf(denom)
-		if amount.GT(sdk.ZeroInt()) {
-			amount = simulation.RandomAmount(r, amount)
+		delegations := k.GetAllDelegatorDelegations(ctx, delegatorAddress)
+		if len(delegations) == 0 {
+			return "no-operation", nil, nil
 		}
-		if amount.Equal(sdk.ZeroInt()) {
+		delegation := delegations[r.Intn(len(delegations))]
+
+		numShares := simulation.RandomDecAmount(r, delegation.Shares)
+		if numShares.Equal(sdk.ZeroDec()) {
 			return "no-operation", nil, nil
 		}
 		msg := stake.MsgBeginUnbonding{
 			DelegatorAddr: delegatorAddress,
-			ValidatorAddr: validatorAddress,
-			SharesAmount:  sdk.NewDecFromInt(amount),
+			ValidatorAddr: delegation.ValidatorAddr,
+			SharesAmount:  numShares,
 		}
 		if msg.ValidateBasic() != nil {
-			return "", nil, fmt.Errorf("expected msg to pass ValidateBasic: %s", msg.GetSignBytes())
+			return "", nil, fmt.Errorf("expected msg to pass ValidateBasic: %s, got error %v",
+				msg.GetSignBytes(), msg.ValidateBasic())
 		}
 		ctx, write := ctx.CacheContext()
 		result := handler(ctx, msg)
@@ -194,10 +196,10 @@ func SimulateMsgBeginRedelegate(m auth.AccountKeeper, k stake.Keeper) simulation
 		action string, fOp []simulation.FutureOperation, err error) {
 
 		denom := k.GetParams(ctx).BondDenom
-		sourceValidatorAcc := simulation.RandomAcc(r, accs)
-		sourceValidatorAddress := sdk.ValAddress(sourceValidatorAcc.Address)
-		destValidatorAcc := simulation.RandomAcc(r, accs)
-		destValidatorAddress := sdk.ValAddress(destValidatorAcc.Address)
+		srcVal := keeper.RandomValidator(r, k, ctx)
+		srcValidatorAddress := srcVal.GetOperator()
+		destVal := keeper.RandomValidator(r, k, ctx)
+		destValidatorAddress := destVal.GetOperator()
 		delegatorAcc := simulation.RandomAcc(r, accs)
 		delegatorAddress := delegatorAcc.Address
 		// TODO
@@ -210,7 +212,7 @@ func SimulateMsgBeginRedelegate(m auth.AccountKeeper, k stake.Keeper) simulation
 		}
 		msg := stake.MsgBeginRedelegate{
 			DelegatorAddr:    delegatorAddress,
-			ValidatorSrcAddr: sourceValidatorAddress,
+			ValidatorSrcAddr: srcValidatorAddress,
 			ValidatorDstAddr: destValidatorAddress,
 			SharesAmount:     sdk.NewDecFromInt(amount),
 		}