Merge pull request onflow#5166 from onflow/ramtin/5129-new-evm-stateD…

…B-part1

[Beyond EVM] performant StateDB implementation - part 1

fvm/evm/emulator/state/account.go

@@ -0,0 +1,62 @@
+package state
+
+import (
+	"math/big"
+
+	gethCommon "github.com/ethereum/go-ethereum/common"
+	gethTypes "github.com/ethereum/go-ethereum/core/types"
+	"github.com/ethereum/go-ethereum/rlp"
+)
+
+// Account holds the metadata of an address and provides (de)serialization functionality
+//
+// Note that code and storage slots of an address is not part of this data structure
+type Account struct {
+	// address
+	Address gethCommon.Address
+	// balance of the address
+	Balance *big.Int
+	// nonce of the address
+	Nonce uint64
+	// hash of the code
+	// if no code the gethTypes.EmptyCodeHash is stored
+	CodeHash gethCommon.Hash
+	// the id of the collection holds storage slots for this account
+	// this value is nil for EOA accounts
+	CollectionID []byte
+}
+
+// NewAccount constructs a new account
+func NewAccount(
+	address gethCommon.Address,
+	balance *big.Int,
+	nonce uint64,
+	codeHash gethCommon.Hash,
+	collectionID []byte,
+) *Account {
+	return &Account{
+		Address:      address,
+		Balance:      balance,
+		Nonce:        nonce,
+		CodeHash:     codeHash,
+		CollectionID: collectionID,
+	}
+}
+
+func (a *Account) HasCode() bool {
+	return a.CodeHash != gethTypes.EmptyCodeHash
+}
+
+// Encode encodes the account
+func (a *Account) Encode() ([]byte, error) {
+	return rlp.EncodeToBytes(a)
+}
+
+// DecodeAccount constructs a new account from the encoded data
+func DecodeAccount(inp []byte) (*Account, error) {
+	if len(inp) == 0 {
+		return nil, nil
+	}
+	a := &Account{}
+	return a, rlp.DecodeBytes(inp, a)
+}

fvm/evm/emulator/state/account_test.go

@@ -0,0 +1,28 @@
+package state_test
+
+import (
+	"testing"
+
+	"github.com/ethereum/go-ethereum/common"
+	"github.com/stretchr/testify/require"
+
+	"github.com/onflow/flow-go/fvm/evm/emulator/state"
+	"github.com/onflow/flow-go/fvm/evm/testutils"
+)
+
+func TestAccountEncoding(t *testing.T) {
+	acc := state.NewAccount(
+		testutils.RandomCommonAddress(t),
+		testutils.RandomBigInt(1000),
+		uint64(2),
+		common.BytesToHash([]byte{1}),
+		[]byte{2},
+	)
+
+	encoded, err := acc.Encode()
+	require.NoError(t, err)
+
+	ret, err := state.DecodeAccount(encoded)
+	require.NoError(t, err)
+	require.Equal(t, acc, ret)
+}