clean up storage and account tombstones from BlockCache when account …

…removal has occurred, for example after SELFDESTRUCT

manager/burrow-mint/state/block_cache.go

@@ -197,6 +197,9 @@ func (cache *BlockCache) Sync() {
 			curStorage = storage
 		}
 		if curAccRemoved {
+			// We should delete any storage for removed accounts in anticipation of
+			// those accounts being reaped from the cache
+			delete(cache.storages, storageKey)
 			continue
 		}
 		value, dirty := cache.storages[storageKey].unpack()
@@ -224,8 +227,12 @@ func (cache *BlockCache) Sync() {
 		if removed {
 			removed := cache.backend.RemoveAccount([]byte(addrStr))
 			if !removed {
-				sanity.PanicCrisis(fmt.Sprintf("Could not remove account to be removed: %X", acc.Address))
+				sanity.PanicCrisis(fmt.Sprintf("Could not remove account to be removed: %X", addrStr))
 			}
+			// Since attempting to delete an already deleted account leads to a
+			// PanicCrisis (above) we must make sure we remove the tombstones of
+			// removed accounts
+			delete(cache.accounts, addrStr)
 		} else {
 			if acc == nil {
 				continue
@@ -259,6 +266,8 @@ func (cache *BlockCache) Sync() {
 			if !removed {
 				sanity.PanicCrisis(fmt.Sprintf("Could not remove namereg entry to be removed: %s", nameStr))
 			}
+			// Remove the tombstone name reg object from the cache
+			delete(cache.names, nameStr)
 		} else {
 			if entry == nil {
 				continue

manager/burrow-mint/state/block_cache_test.go

@@ -0,0 +1,103 @@
+package state
+
+import (
+	"testing"
+
+	"fmt"
+
+	"github.com/hyperledger/burrow/account"
+	"github.com/hyperledger/burrow/core/types"
+	"github.com/hyperledger/burrow/genesis"
+	ptypes "github.com/hyperledger/burrow/permission/types"
+	"github.com/stretchr/testify/assert"
+	"github.com/tendermint/go-db"
+)
+
+func TestBlockCache_Sync_Accounts(t *testing.T) {
+	blockCache := NewBlockCache(stateForBlockCache(t, 10))
+	blockCache.RemoveAccount(accountAddress(1))
+	blockCache.Sync()
+	// Expect account cache objects to be reaped so that an attempt is not made
+	// to remove them twice from merkle tree
+	defer func() {
+		if r := recover(); r != nil {
+			t.Fatalf("Consecutive calls to BlockCache.Sync() failed. " +
+					"Is cache dirty?\n Error: %s", r)
+		}
+	}()
+	blockCache.Sync()
+}
+
+func TestBlockCache_Sync_NameReg(t *testing.T) {
+	blockCache := NewBlockCache(stateForBlockCache(t, 10))
+	blockCache.RemoveAccount(accountAddress(1))
+	nameRegName := "foobs"
+	nameRegEntry := &types.NameRegEntry{
+		Name:    nameRegName,
+		Owner:   accountAddress(1),
+		Data:    "Dates",
+		Expires: 434,
+	}
+	blockCache.UpdateNameRegEntry(nameRegEntry)
+	blockCache.Sync()
+	blockCache.RemoveNameRegEntry(nameRegName)
+	// Expect name reg cache objects to be reaped so that an attempt is not made
+	// to remove them twice from merkle tree
+	blockCache.Sync()
+	defer func() {
+		if r := recover(); r != nil {
+			t.Fatalf("Consecutive calls to BlockCache.Sync() failed. " +
+					"Is cache dirty?\n Error: %s", r)
+		}
+	}()
+	blockCache.Sync()
+}
+
+func stateForBlockCache(t *testing.T, numAccounts byte) *State {
+	genAccounts := make([]*genesis.GenesisAccount, numAccounts)
+	genValidators := make([]*genesis.GenesisValidator, 1)
+	for i := byte(0); i < numAccounts; i++ {
+		genAccounts[i] = genesisAccount("account", i)
+	}
+	genValidators[0] = genesisValidator("validator", 0)
+	genDoc, err := genesis.MakeGenesisDocFromAccounts("BlockChainTest",
+		genAccounts, genValidators)
+	assert.NoError(t, err)
+	return MakeGenesisState(db.NewMemDB(), &genDoc)
+}
+
+func genesisAccount(prefix string, index byte) *genesis.GenesisAccount {
+	address := accountAddress(index)
+	return &genesis.GenesisAccount{
+		Address:     address,
+		Amount:      10000 + int64(index),
+		Name:        accountName(prefix, index, address),
+		Permissions: &ptypes.DefaultAccountPermissions,
+	}
+}
+
+func genesisValidator(prefix string, index byte) *genesis.GenesisValidator {
+	privAccount := account.GenPrivAccountFromSecret(
+		fmt.Sprintf("%s_%v", prefix, index))
+	return &genesis.GenesisValidator{
+		PubKey: privAccount.PubKey,
+		Amount: 1000000 + int64(index),
+		Name:   accountName(prefix, index, privAccount.Address),
+		UnbondTo: []genesis.BasicAccount{
+			{
+				Address: privAccount.Address,
+				Amount:  100,
+			},
+		},
+	}
+}
+
+func accountName(prefix string, index byte, address []byte) string {
+	return fmt.Sprintf("%s-%v_%X", prefix, index, address)
+}
+
+func accountAddress(index byte) []byte {
+	var address [20]byte
+	address[19] = index
+	return address[:]
+}