prysm-pulse/beacon-chain/blockchain/core_test.go

package blockchain

import (
	"bytes"
	"context"
	"errors"
	"reflect"
	"testing"
	"time"

	"github.com/ethereum/go-ethereum/common"
	gethTypes "github.com/ethereum/go-ethereum/core/types"
	"github.com/gogo/protobuf/proto"
	"github.com/golang/protobuf/ptypes/timestamp"
	"github.com/prysmaticlabs/prysm/beacon-chain/params"
	"github.com/prysmaticlabs/prysm/beacon-chain/types"
	"github.com/prysmaticlabs/prysm/beacon-chain/utils"
	pb "github.com/prysmaticlabs/prysm/proto/beacon/p2p/v1"
	"github.com/prysmaticlabs/prysm/shared/database"
	logTest "github.com/sirupsen/logrus/hooks/test"
)

// FakeClock represents an mocked clock for testing purposes.
type fakeClock struct{}

// Now represents the mocked functionality of a Clock.Now().
func (fakeClock) Now() time.Time {
	return time.Date(1970, 2, 1, 1, 0, 0, 0, time.UTC)
}

type faultyFetcher struct{}

func (f *faultyFetcher) BlockByHash(ctx context.Context, hash common.Hash) (*gethTypes.Block, error) {
	return nil, errors.New("cannot fetch block")
}

type mockFetcher struct{}

func (m *mockFetcher) BlockByHash(ctx context.Context, hash common.Hash) (*gethTypes.Block, error) {
	block := gethTypes.NewBlock(&gethTypes.Header{}, nil, nil, nil)
	return block, nil
}

func startInMemoryBeaconChain(t *testing.T) (*BeaconChain, *database.DB) {
	config := &database.DBConfig{DataDir: "", Name: "", InMemory: true}
	db, err := database.NewDB(config)
	if err != nil {
		t.Fatalf("unable to setup db: %v", err)
	}
	beaconChain, err := NewBeaconChain(db.DB())
	if err != nil {
		t.Fatalf("unable to setup beacon chain: %v", err)
	}

	return beaconChain, db
}

func TestNewBeaconChain(t *testing.T) {
	hook := logTest.NewGlobal()
	beaconChain, db := startInMemoryBeaconChain(t)
	defer db.Close()

	msg := hook.LastEntry().Message
	want := "No chainstate found on disk, initializing beacon from genesis"
	if msg != want {
		t.Errorf("incorrect log, expected %s, got %s", want, msg)
	}

	hook.Reset()
	active, crystallized := types.NewGenesisStates()
	if _, err := types.NewGenesisBlock(); err != nil {
		t.Errorf("Creating a new genesis block failed %v", err)
	}
	if !reflect.DeepEqual(beaconChain.ActiveState(), active) {
		t.Errorf("active states not equal. received: %v, wanted: %v", beaconChain.ActiveState(), active)
	}
	if !reflect.DeepEqual(beaconChain.CrystallizedState(), crystallized) {
		t.Errorf("crystallized states not equal. received: %v, wanted: %v", beaconChain.CrystallizedState(), crystallized)
	}
	if _, err := beaconChain.GenesisBlock(); err != nil {
		t.Errorf("Getting new beaconchain genesis failed: %v", err)
	}
}

func TestGetGenesisBlock(t *testing.T) {
	beaconChain, db := startInMemoryBeaconChain(t)
	defer db.Close()

	block := &pb.BeaconBlock{
		ParentHash: make([]byte, 32),
		Timestamp: &timestamp.Timestamp{
			Seconds: 13000000,
		},
	}
	bytes, err := proto.Marshal(block)
	if err != nil {
		t.Errorf("unable to Marshal genesis block: %v", err)
	}

	if err := db.DB().Put([]byte("genesis"), bytes); err != nil {
		t.Errorf("unable to save key value of genesis: %v", err)
	}

	genesisBlock, err := beaconChain.GenesisBlock()
	if err != nil {
		t.Errorf("unable to get key value of genesis: %v", err)
	}

	time, err := genesisBlock.Timestamp()
	if err != nil {
		t.Errorf("Timestamp could not be retrieved: %v", err)
	}
	if time.Second() != 40 {
		t.Errorf("Timestamp was not saved properly: %v", time.Second())
	}
}

func TestSetActiveState(t *testing.T) {
	beaconChain, db := startInMemoryBeaconChain(t)
	defer db.Close()

	data := &pb.ActiveState{
		TotalAttesterDeposits: 4096,
		AttesterBitfield:      []byte{'A', 'B', 'C'},
	}
	active := types.NewActiveState(data)

	if err := beaconChain.SetActiveState(active); err != nil {
		t.Fatalf("unable to mutate active state: %v", err)
	}
	if !reflect.DeepEqual(beaconChain.state.ActiveState, active) {
		t.Errorf("active state was not updated. wanted %v, got %v", active, beaconChain.state.ActiveState)
	}

	// Initializing a new beacon chain should deserialize persisted state from disk.
	newBeaconChain, err := NewBeaconChain(db.DB())
	if err != nil {
		t.Fatalf("unable to setup second beacon chain: %v", err)
	}

	// The active state should still be the one we mutated and persited earlier.
	if active.TotalAttesterDeposits() != newBeaconChain.state.ActiveState.TotalAttesterDeposits() {
		t.Errorf("active state height incorrect. wanted %v, got %v", active.TotalAttesterDeposits(), newBeaconChain.state.ActiveState.TotalAttesterDeposits())
	}
	if !bytes.Equal(active.AttesterBitfield(), newBeaconChain.state.ActiveState.AttesterBitfield()) {
		t.Errorf("active state randao incorrect. wanted %v, got %v", active.AttesterBitfield(), newBeaconChain.state.ActiveState.AttesterBitfield())
	}
}

func TestSetCrystallizedState(t *testing.T) {
	beaconChain, db := startInMemoryBeaconChain(t)
	defer db.Close()

	data := &pb.CrystallizedState{
		CurrentDynasty:    3,
		CurrentCheckPoint: []byte("checkpoint"),
	}
	crystallized := types.NewCrystallizedState(data)

	if err := beaconChain.SetCrystallizedState(crystallized); err != nil {
		t.Fatalf("unable to mutate crystallized state: %v", err)
	}
	if !reflect.DeepEqual(beaconChain.state.CrystallizedState, crystallized) {
		t.Errorf("crystallized state was not updated. wanted %v, got %v", crystallized, beaconChain.state.CrystallizedState)
	}

	// Initializing a new beacon chain should deserialize persisted state from disk.
	newBeaconChain, err := NewBeaconChain(db.DB())
	if err != nil {
		t.Fatalf("unable to setup second beacon chain: %v", err)
	}

	// The crystallized state should still be the one we mutated and persited earlier.
	if crystallized.CurrentDynasty() != newBeaconChain.state.CrystallizedState.CurrentDynasty() {
		t.Errorf("crystallized state dynasty incorrect. wanted %v, got %v", crystallized.CurrentDynasty(), newBeaconChain.state.CrystallizedState.CurrentDynasty())
	}
	if crystallized.CurrentCheckPoint().Hex() != newBeaconChain.state.CrystallizedState.CurrentCheckPoint().Hex() {
		t.Errorf("crystallized state current checkpoint incorrect. wanted %v, got %v", crystallized.CurrentCheckPoint().Hex(), newBeaconChain.state.CrystallizedState.CurrentCheckPoint().Hex())
	}
}

func TestGetAttestersProposer(t *testing.T) {
	beaconChain, db := startInMemoryBeaconChain(t)
	defer db.Close()

	var validators []*pb.ValidatorRecord
	// Create 1000 validators in ActiveValidators.
	for i := 0; i < 1000; i++ {
		validator := &pb.ValidatorRecord{WithdrawalAddress: []byte{'A'}, PublicKey: 0}
		validators = append(validators, validator)
	}

	_, crystallized := types.NewGenesisStates()
	crystallized.SetActiveValidators(validators)
	beaconChain.SetCrystallizedState(crystallized)

	attesters, proposer, err := beaconChain.getAttestersProposer(common.Hash{'A'})
	if err != nil {
		t.Errorf("GetAttestersProposer function failed: %v", err)
	}

	validatorList, err := utils.ShuffleIndices(common.Hash{'A'}, len(validators))
	if err != nil {
		t.Errorf("Shuffle function function failed: %v", err)
	}

	if !reflect.DeepEqual(proposer, validatorList[len(validatorList)-1]) {
		t.Errorf("Get proposer failed, expected: %v got: %v", validatorList[len(validatorList)-1], proposer)
	}
	if !reflect.DeepEqual(attesters, validatorList[:len(attesters)]) {
		t.Errorf("Get attesters failed, expected: %v got: %v", validatorList[:len(attesters)], attesters)
	}
}

func TestCanProcessBlock(t *testing.T) {
	beaconChain, db := startInMemoryBeaconChain(t)
	defer db.Close()

	clock = &fakeClock{}

	// Initialize a parent block
	parentBlock := NewBlock(t, &pb.BeaconBlock{
		SlotNumber: 1,
	})
	parentHash, err := parentBlock.Hash()
	if err != nil {
		t.Fatalf("Failed to compute parent block's hash: %v", err)
	}
	if err = db.DB().Put(parentHash[:], []byte{}); err != nil {
		t.Fatalf("Failed to put parent block on db: %v", err)
	}

	// Using a faulty fetcher should throw an error.
	block := NewBlock(t, &pb.BeaconBlock{
		SlotNumber: 2,
	})
	if _, err := beaconChain.CanProcessBlock(&faultyFetcher{}, block); err == nil {
		t.Error("Using a faulty fetcher should throw an error, received nil")
	}

	// Initialize initial state
	activeState := types.NewActiveState(&pb.ActiveState{TotalAttesterDeposits: 10000})
	beaconChain.state.ActiveState = activeState
	activeHash, err := activeState.Hash()
	if err != nil {
		t.Fatalf("Cannot hash active state: %v", err)
	}

	crystallized := types.NewCrystallizedState(&pb.CrystallizedState{CurrentEpoch: 5})
	beaconChain.state.CrystallizedState = crystallized
	crystallizedHash, err := crystallized.Hash()
	if err != nil {
		t.Fatalf("Compute crystallized state hash failed: %v", err)
	}

	block = NewBlock(t, &pb.BeaconBlock{
		SlotNumber:            2,
		ActiveStateHash:       activeHash[:],
		CrystallizedStateHash: crystallizedHash[:],
		ParentHash:            parentHash[:],
	})

	// A properly initialize block should not fail
	canProcess, err := beaconChain.CanProcessBlock(&mockFetcher{}, block)
	if err != nil {
		t.Fatalf("CanProcessBlocks failed: %v", err)
	}
	if !canProcess {
		t.Error("Should be able to process block, could not")
	}

	// Test timestamp validity condition
	block = NewBlock(t, &pb.BeaconBlock{
		SlotNumber:            1000000,
		ActiveStateHash:       activeHash[:],
		CrystallizedStateHash: crystallizedHash[:],
		ParentHash:            parentHash[:],
	})
	canProcess, err = beaconChain.CanProcessBlock(&mockFetcher{}, block)
	if err != nil {
		t.Fatalf("CanProcessBlocks failed: %v", err)
	}
	if canProcess {
		t.Error("Should not be able to process block with invalid timestamp condition")
	}
}

func TestProcessBlockWithBadHashes(t *testing.T) {
	beaconChain, db := startInMemoryBeaconChain(t)
	defer db.Close()

	// Test negative scenario where active state hash is different than node's compute
	parentBlock := NewBlock(t, nil)
	parentHash, err := parentBlock.Hash()
	if err != nil {
		t.Fatalf("Failed to compute parent block's hash: %v", err)
	}
	if err = db.DB().Put(parentHash[:], []byte{}); err != nil {
		t.Fatalf("Failed to put parent block on db: %v", err)
	}

	// Initialize state
	active := types.NewActiveState(&pb.ActiveState{TotalAttesterDeposits: 10000})
	activeStateHash, err := active.Hash()
	if err != nil {
		t.Fatalf("Cannot hash active state: %v", err)
	}
	crystallized := types.NewCrystallizedState(&pb.CrystallizedState{CurrentEpoch: 10000})
	crystallizedStateHash, err := crystallized.Hash()
	if err != nil {
		t.Fatalf("Cannot hash crystallized state: %v", err)
	}

	block := NewBlock(t, &pb.BeaconBlock{
		SlotNumber:            1,
		ActiveStateHash:       activeStateHash[:],
		CrystallizedStateHash: crystallizedStateHash[:],
		ParentHash:            parentHash[:],
	})

	// Test negative scenario where active state hash is different than node's compute
	beaconChain.state.ActiveState = types.NewActiveState(&pb.ActiveState{TotalAttesterDeposits: 9999})

	canProcess, err := beaconChain.CanProcessBlock(&mockFetcher{}, block)
	if err == nil {
		t.Fatal("CanProcessBlocks should have failed with diff state hashes")
	}
	if canProcess {
		t.Error("CanProcessBlocks should have returned false")
	}

	// Test negative scenario where crystallized state hash is different than node's compute
	beaconChain.state.CrystallizedState = types.NewCrystallizedState(&pb.CrystallizedState{CurrentEpoch: 9999})

	canProcess, err = beaconChain.CanProcessBlock(&mockFetcher{}, block)
	if err == nil {
		t.Fatal("CanProcessBlocks should have failed with diff state hashes")
	}
	if canProcess {
		t.Error("CanProcessBlocks should have returned false")
	}
}

func TestProcessBlockWithInvalidParent(t *testing.T) {
	beaconChain, db := startInMemoryBeaconChain(t)
	defer db.Close()

	// If parent hash is non-existent, processing block should fail.
	active := types.NewActiveState(&pb.ActiveState{TotalAttesterDeposits: 10000})
	activeStateHash, err := active.Hash()
	if err != nil {
		t.Fatalf("Cannot hash active state: %v", err)
	}
	beaconChain.state.ActiveState = active

	crystallized := types.NewCrystallizedState(&pb.CrystallizedState{CurrentEpoch: 10000})
	crystallizedStateHash, err := crystallized.Hash()
	if err != nil {
		t.Fatalf("Cannot hash crystallized state: %v", err)
	}
	beaconChain.state.CrystallizedState = crystallized

	// Test that block processing is invalid without a parent hash
	block := NewBlock(t, &pb.BeaconBlock{
		SlotNumber:            2,
		ActiveStateHash:       activeStateHash[:],
		CrystallizedStateHash: crystallizedStateHash[:],
	})
	if _, err = beaconChain.CanProcessBlock(&mockFetcher{}, block); err == nil {
		t.Error("Processing without a valid parent hash should fail")
	}

	// If parent hash is not stored in db, processing block should fail.
	parentBlock := NewBlock(t, &pb.BeaconBlock{
		SlotNumber: 1,
	})
	parentHash, err := parentBlock.Hash()
	if err != nil {
		t.Fatalf("Failed to compute parent block's hash: %v", err)
	}
	block = NewBlock(t, &pb.BeaconBlock{
		SlotNumber:            2,
		ActiveStateHash:       activeStateHash[:],
		CrystallizedStateHash: crystallizedStateHash[:],
		ParentHash:            parentHash[:],
	})

	if _, err := beaconChain.CanProcessBlock(&mockFetcher{}, block); err == nil {
		t.Error("Processing block should fail when parent hash is not in db")
	}

	if err = db.DB().Put(parentHash[:], nil); err != nil {
		t.Fatalf("Failed to put parent block on db: %v", err)
	}
	_, err = beaconChain.CanProcessBlock(&mockFetcher{}, block)
	if err == nil {
		t.Error("Processing block should fail when parent hash points to nil in db")
	}
	want := "parent hash points to nil in beaconDB"
	if err.Error() != want {
		t.Errorf("invalid log, expected \"%s\", got \"%s\"", want, err.Error())
	}

	if err = db.DB().Put(parentHash[:], []byte{}); err != nil {
		t.Fatalf("Failed to put parent block on db: %v", err)
	}

	canProcess, err := beaconChain.CanProcessBlock(&mockFetcher{}, block)
	if err != nil {
		t.Errorf("Should have been able to process block: %v", err)
	}
	if !canProcess {
		t.Error("Should have been able to process block")
	}
}

func TestRotateValidatorSet(t *testing.T) {
	beaconChain, db := startInMemoryBeaconChain(t)
	defer db.Close()

	activeValidators := []*pb.ValidatorRecord{
		{Balance: 10000, WithdrawalAddress: []byte{'A'}},
		{Balance: 15000, WithdrawalAddress: []byte{'B'}},
		{Balance: 20000, WithdrawalAddress: []byte{'C'}},
		{Balance: 25000, WithdrawalAddress: []byte{'D'}},
		{Balance: 30000, WithdrawalAddress: []byte{'E'}},
	}

	queuedValidators := []*pb.ValidatorRecord{
		{Balance: params.DefaultBalance, WithdrawalAddress: []byte{'F'}},
		{Balance: params.DefaultBalance, WithdrawalAddress: []byte{'G'}},
		{Balance: params.DefaultBalance, WithdrawalAddress: []byte{'H'}},
		{Balance: params.DefaultBalance, WithdrawalAddress: []byte{'I'}},
		{Balance: params.DefaultBalance, WithdrawalAddress: []byte{'J'}},
	}

	exitedValidators := []*pb.ValidatorRecord{
		{Balance: 99999, WithdrawalAddress: []byte{'K'}},
		{Balance: 99999, WithdrawalAddress: []byte{'L'}},
		{Balance: 99999, WithdrawalAddress: []byte{'M'}},
		{Balance: 99999, WithdrawalAddress: []byte{'N'}},
		{Balance: 99999, WithdrawalAddress: []byte{'O'}},
	}

	beaconChain.CrystallizedState().SetActiveValidators(activeValidators)
	beaconChain.CrystallizedState().SetQueuedValidators(queuedValidators)
	beaconChain.CrystallizedState().SetExitedValidators(exitedValidators)

	if beaconChain.CrystallizedState().ActiveValidatorsLength() != 5 {
		t.Errorf("Get active validator count failed, wanted 5, got %v", beaconChain.CrystallizedState().ActiveValidatorsLength())
	}
	if beaconChain.CrystallizedState().QueuedValidatorsLength() != 5 {
		t.Errorf("Get queued validator count failed, wanted 5, got %v", beaconChain.CrystallizedState().QueuedValidatorsLength())
	}
	if beaconChain.CrystallizedState().ExitedValidatorsLength() != 5 {
		t.Errorf("Get exited validator count failed, wanted 5, got %v", beaconChain.CrystallizedState().ExitedValidatorsLength())
	}

	newQueuedValidators, newActiveValidators, newExitedValidators := beaconChain.rotateValidatorSet()

	if len(newActiveValidators) != 4 {
		t.Errorf("Get active validator count failed, wanted 5, got %v", len(newActiveValidators))
	}
	if len(newQueuedValidators) != 4 {
		t.Errorf("Get queued validator count failed, wanted 4, got %v", len(newQueuedValidators))
	}
	if len(newExitedValidators) != 7 {
		t.Errorf("Get exited validator count failed, wanted 6, got %v", len(newExitedValidators))
	}
}

func TestIsEpochTransition(t *testing.T) {
	beaconChain, db := startInMemoryBeaconChain(t)
	defer db.Close()

	if err := beaconChain.SetCrystallizedState(types.NewCrystallizedState(&pb.CrystallizedState{CurrentEpoch: 1})); err != nil {
		t.Fatalf("unable to mutate crystallizedstate: %v", err)
	}
	if !beaconChain.IsEpochTransition(128) {
		t.Errorf("there was supposed to be an epoch transition but there isn't one now")
	}
	if beaconChain.IsEpochTransition(80) {
		t.Errorf("there is not supposed to be an epoch transition but there is one now")
	}
}

func TestHasVoted(t *testing.T) {
	beaconChain, db := startInMemoryBeaconChain(t)
	defer db.Close()

	// Setting bit field to 11111111
	beaconChain.ActiveState().SetAttesterBitfield([]byte{255})

	for i := 0; i < len(beaconChain.ActiveState().AttesterBitfield()); i++ {
		voted, err := beaconChain.hasAttesterAtIndexVoted(i)
		if err != nil {
			t.Errorf("checking bitfield for vote failed: %v", err)
		}
		if !voted {
			t.Error("validator voted but received didn't vote")
		}
	}

	// Setting bit field to 01010101
	beaconChain.ActiveState().SetAttesterBitfield([]byte{85})

	for i := 0; i < len(beaconChain.ActiveState().AttesterBitfield()); i++ {
		voted, err := beaconChain.hasAttesterAtIndexVoted(i)
		if err != nil {
			t.Errorf("checking bitfield for vote failed: %v", err)
		}
		if i%2 == 0 && voted {
			t.Error("validator didn't vote but received voted")
		}
		if i%2 == 1 && !voted {
			t.Error("validator voted but received didn't vote")
		}
	}
}

func TestResetAttesterBitfields(t *testing.T) {
	beaconChain, db := startInMemoryBeaconChain(t)
	defer db.Close()

	// Testing validator set sizes from 1 to 100.
	for j := 1; j <= 100; j++ {
		var validators []*pb.ValidatorRecord

		for i := 0; i < j; i++ {
			validator := &pb.ValidatorRecord{WithdrawalAddress: []byte{}, PublicKey: 0}
			validators = append(validators, validator)
		}

		beaconChain.CrystallizedState().SetActiveValidators(validators)

		testAttesterBitfield := []byte{2, 4, 6, 9}
		if err := beaconChain.SetActiveState(types.NewActiveState(&pb.ActiveState{AttesterBitfield: testAttesterBitfield})); err != nil {
			t.Fatal("unable to mutate active state")
		}

		beaconChain.resetAttesterBitfield()

		if bytes.Equal(testAttesterBitfield, beaconChain.state.ActiveState.AttesterBitfield()) {
			t.Fatalf("attester bitfields have not been able to be reset: %v", testAttesterBitfield)
		}

		bitfieldLength := j / 8

		if !bytes.Equal(beaconChain.state.ActiveState.AttesterBitfield(), make([]byte, bitfieldLength)) {
			t.Fatalf("attester bitfields are not zeroed out: %v", beaconChain.state.ActiveState.AttesterBitfield())
		}
	}
}

func TestResetTotalAttesterDeposit(t *testing.T) {
	beaconChain, db := startInMemoryBeaconChain(t)
	defer db.Close()

	active := types.NewActiveState(&pb.ActiveState{TotalAttesterDeposits: 10000})
	if err := beaconChain.SetActiveState(active); err != nil {
		t.Fatalf("unable to Mutate Active state: %v", err)
	}
	if beaconChain.state.ActiveState.TotalAttesterDeposits() != uint64(10000) {
		t.Fatalf("attester deposit was not saved: %d", beaconChain.state.ActiveState.TotalAttesterDeposits())
	}
	beaconChain.ActiveState().SetTotalAttesterDeposits(0)
	if beaconChain.state.ActiveState.TotalAttesterDeposits() != uint64(0) {
		t.Fatalf("attester deposit was not able to be reset: %d", beaconChain.state.ActiveState.TotalAttesterDeposits())
	}
}

func TestUpdateJustifiedEpoch(t *testing.T) {
	beaconChain, db := startInMemoryBeaconChain(t)
	defer db.Close()

	data := &pb.CrystallizedState{CurrentEpoch: 5, LastJustifiedEpoch: 4, LastFinalizedEpoch: 3}
	beaconChain.SetCrystallizedState(types.NewCrystallizedState(data))

	if beaconChain.state.CrystallizedState.LastFinalizedEpoch() != uint64(3) ||
		beaconChain.state.CrystallizedState.LastJustifiedEpoch() != uint64(4) ||
		beaconChain.state.CrystallizedState.CurrentEpoch() != uint64(5) {
		t.Fatal("crystallized state unable to be saved")
	}

	beaconChain.state.CrystallizedState.UpdateJustifiedEpoch()

	if beaconChain.state.CrystallizedState.LastJustifiedEpoch() != uint64(5) {
		t.Fatalf("unable to update last justified epoch: %d", beaconChain.state.CrystallizedState.LastJustifiedEpoch())
	}
	if beaconChain.state.CrystallizedState.LastFinalizedEpoch() != uint64(4) {
		t.Fatalf("unable to update last finalized epoch: %d", beaconChain.state.CrystallizedState.LastFinalizedEpoch())
	}

	data = &pb.CrystallizedState{CurrentEpoch: 8, LastJustifiedEpoch: 4, LastFinalizedEpoch: 3}
	beaconChain.SetCrystallizedState(types.NewCrystallizedState(data))

	if beaconChain.state.CrystallizedState.LastFinalizedEpoch() != uint64(3) ||
		beaconChain.state.CrystallizedState.LastJustifiedEpoch() != uint64(4) ||
		beaconChain.state.CrystallizedState.CurrentEpoch() != uint64(8) {
		t.Fatal("crystallized state unable to be saved")
	}

	beaconChain.state.CrystallizedState.UpdateJustifiedEpoch()

	if beaconChain.state.CrystallizedState.LastJustifiedEpoch() != uint64(8) {
		t.Fatalf("unable to update last justified epoch: %d", beaconChain.state.CrystallizedState.LastJustifiedEpoch())
	}
	if beaconChain.state.CrystallizedState.LastFinalizedEpoch() != uint64(3) {
		t.Fatalf("unable to update last finalized epoch: %d", beaconChain.state.CrystallizedState.LastFinalizedEpoch())
	}
}

func TestComputeValidatorRewardsAndPenalties(t *testing.T) {
	beaconChain, db := startInMemoryBeaconChain(t)
	defer db.Close()

	var validators []*pb.ValidatorRecord
	for i := 0; i < 40; i++ {
		validator := &pb.ValidatorRecord{Balance: 1000, WithdrawalAddress: []byte{'A'}, PublicKey: 0}
		validators = append(validators, validator)
	}

	data := &pb.CrystallizedState{
		ActiveValidators:   validators,
		CurrentCheckPoint:  []byte("checkpoint"),
		TotalDeposits:      40000,
		CurrentEpoch:       5,
		LastJustifiedEpoch: 4,
		LastFinalizedEpoch: 3,
	}
	if err := beaconChain.SetCrystallizedState(types.NewCrystallizedState(data)); err != nil {
		t.Fatalf("unable to mutate crystallizedstate: %v", err)
	}

	//Binary representation of bitfield: 11001000 10010100 10010010 10110011 00110001
	testAttesterBitfield := []byte{200, 148, 146, 179, 49}
	types.NewActiveState(&pb.ActiveState{AttesterBitfield: testAttesterBitfield})
	ActiveState := types.NewActiveState(&pb.ActiveState{TotalAttesterDeposits: 40000, AttesterBitfield: testAttesterBitfield})
	if err := beaconChain.SetActiveState(ActiveState); err != nil {
		t.Fatalf("unable to Mutate Active state: %v", err)
	}
	if err := beaconChain.calculateRewardsFFG(); err != nil {
		t.Fatalf("could not compute validator rewards and penalties: %v", err)
	}
	if beaconChain.state.CrystallizedState.LastJustifiedEpoch() != uint64(5) {
		t.Fatalf("unable to update last justified epoch: %d", beaconChain.state.CrystallizedState.LastJustifiedEpoch())
	}
	if beaconChain.state.CrystallizedState.LastFinalizedEpoch() != uint64(4) {
		t.Fatalf("unable to update last finalized epoch: %d", beaconChain.state.CrystallizedState.LastFinalizedEpoch())
	}
	if beaconChain.CrystallizedState().ActiveValidators()[0].Balance != uint64(1001) {
		t.Fatalf("validator balance not updated: %d", beaconChain.CrystallizedState().ActiveValidators()[1].Balance)
	}
	if beaconChain.CrystallizedState().ActiveValidators()[7].Balance != uint64(999) {
		t.Fatalf("validator balance not updated: %d", beaconChain.CrystallizedState().ActiveValidators()[1].Balance)
	}
	if beaconChain.CrystallizedState().ActiveValidators()[29].Balance != uint64(999) {
		t.Fatalf("validator balance not updated: %d", beaconChain.CrystallizedState().ActiveValidators()[1].Balance)
	}
	if beaconChain.state.ActiveState.TotalAttesterDeposits() != uint64(0) {
		t.Fatalf("attester deposit was not able to be reset: %d", beaconChain.state.ActiveState.TotalAttesterDeposits())
	}
	if !bytes.Equal(beaconChain.state.ActiveState.AttesterBitfield(), make([]byte, 5)) {
		t.Fatalf("attester bitfields are not zeroed out: %v", beaconChain.state.ActiveState.AttesterBitfield())
	}
}

// NewBlock is a helper method to create blocks with valid defaults.
// For a generic block, use NewBlock(t, nil)
func NewBlock(t *testing.T, b *pb.BeaconBlock) *types.Block {
	if b == nil {
		b = &pb.BeaconBlock{}
	}
	if b.ActiveStateHash == nil {
		b.ActiveStateHash = make([]byte, 32)
	}
	if b.CrystallizedStateHash == nil {
		b.CrystallizedStateHash = make([]byte, 32)
	}
	if b.ParentHash == nil {
		b.ParentHash = make([]byte, 32)
	}

	blk, err := types.NewBlock(b)
	if err != nil {
		t.Fatalf("failed to instantiate block with slot number: %v", err)
	}
	return blk
}