rlp, trie, triedb/pathdb: compress trienode hsitory

rlp/raw.go

@@ -17,6 +17,7 @@
 package rlp
 
 import (
+	"fmt"
 	"io"
 	"reflect"
 )
@@ -152,6 +153,35 @@ func CountValues(b []byte) (int, error) {
 	return i, nil
 }
 
+// SplitListValues extracts the raw elements from the list RLP-encoding blob.
+func SplitListValues(b []byte) ([][]byte, error) {
+	b, _, err := SplitList(b)
+	if err != nil {
+		return nil, fmt.Errorf("decode error: %v", err)
+	}
+	var elements [][]byte
+	for len(b) > 0 {
+		_, tagsize, size, err := readKind(b)
+		if err != nil {
+			return nil, err
+		}
+		elements = append(elements, b[:tagsize+size])
+		b = b[tagsize+size:]
+	}
+	return elements, nil
+}
+
+// MergeListValues takes a list of raw elements and rlp-encodes them as list.
+func MergeListValues(elems [][]byte) ([]byte, error) {
+	w := NewEncoderBuffer(nil)
+	offset := w.List()
+	for _, elem := range elems {
+		w.Write(elem)
+	}
+	w.ListEnd(offset)
+	return w.ToBytes(), nil
+}
+
 func readKind(buf []byte) (k Kind, tagsize, contentsize uint64, err error) {
 	if len(buf) == 0 {
 		return 0, 0, 0, io.ErrUnexpectedEOF

trie/node.go

@@ -17,6 +17,7 @@
 package trie
 
 import (
+	"bytes"
 	"fmt"
 	"io"
 	"strings"
@@ -242,6 +243,74 @@ func decodeRef(buf []byte) (node, []byte, error) {
 	}
 }
 
+// decodeNodeElements parses the RLP encoding of a trie node and returns all the
+// elements in raw byte format.
+//
+// For full node, it returns a slice of 17 elements;
+// For short node, it returns a slice of 2 elements;
+func decodeNodeElements(buf []byte) ([][]byte, error) {
+	if len(buf) == 0 {
+		return nil, io.ErrUnexpectedEOF
+	}
+	return rlp.SplitListValues(buf)
+}
+
+// encodeNodeElements encodes the provided node elements into a rlp list.
+func encodeNodeElements(elements [][]byte) ([]byte, error) {
+	if len(elements) != 2 && len(elements) != 17 {
+		return nil, fmt.Errorf("invalid number of elements: %d", len(elements))
+	}
+	return rlp.MergeListValues(elements)
+}
+
+// NodeDifference accepts two RLP-encoding nodes and figures out the difference
+// between them.
+//
+// An error is returned if any of the provided blob is nil, or the type of nodes
+// are different.
+func NodeDifference(oldvalue []byte, newvalue []byte) (int, []int, [][]byte, error) {
+	oldElems, err := decodeNodeElements(oldvalue)
+	if err != nil {
+		return 0, nil, nil, err
+	}
+	newElems, err := decodeNodeElements(newvalue)
+	if err != nil {
+		return 0, nil, nil, err
+	}
+	if len(oldElems) != len(newElems) {
+		return 0, nil, nil, fmt.Errorf("different node type, old elements: %d, new elements: %d", len(oldElems), len(newElems))
+	}
+	var (
+		indices = make([]int, 0, len(oldElems))
+		diff    = make([][]byte, 0, len(oldElems))
+	)
+	for i := 0; i < len(oldElems); i++ {
+		if !bytes.Equal(oldElems[i], newElems[i]) {
+			indices = append(indices, i)
+			diff = append(diff, oldElems[i])
+		}
+	}
+	return len(oldElems), indices, diff, nil
+}
+
+// ReassembleNode accepts a RLP-encoding node along with a set of mutations,
+// applying the modification diffs according to the indices and re-assemble.
+func ReassembleNode(blob []byte, mutations [][][]byte, indices [][]int) ([]byte, error) {
+	if len(mutations) == 0 && len(indices) == 0 {
+		return blob, nil
+	}
+	elements, err := decodeNodeElements(blob)
+	if err != nil {
+		return nil, err
+	}
+	for i := 0; i < len(mutations); i++ {
+		for j, pos := range indices[i] {
+			elements[pos] = mutations[i][j]
+		}
+	}
+	return encodeNodeElements(elements)
+}
+
 // wraps a decoding error with information about the path to the
 // invalid child node (for debugging encoding issues).
 type decodeError struct {

trie/node_test.go

@@ -18,9 +18,12 @@ package trie
 
 import (
 	"bytes"
+	"math/rand"
+	"reflect"
 	"testing"
 
 	"github.com/ethereum/go-ethereum/crypto"
+	"github.com/ethereum/go-ethereum/internal/testrand"
 	"github.com/ethereum/go-ethereum/rlp"
 )
 
@@ -94,6 +97,286 @@ func TestDecodeFullNode(t *testing.T) {
 	}
 }
 
+func makeTestLeafNode(small bool) []byte {
+	l := leafNodeEncoder{}
+	l.Key = hexToCompact(keybytesToHex(testrand.Bytes(10)))
+	if small {
+		l.Val = testrand.Bytes(10)
+	} else {
+		l.Val = testrand.Bytes(32)
+	}
+	buf := rlp.NewEncoderBuffer(nil)
+	l.encode(buf)
+	return buf.ToBytes()
+}
+
+func makeTestFullNode(small bool) []byte {
+	n := fullnodeEncoder{}
+	for i := 0; i < 16; i++ {
+		switch rand.Intn(3) {
+		case 0:
+			// write nil
+		case 1:
+			// write hash
+			n.Children[i] = testrand.Bytes(32)
+		case 2:
+			// write embedded node
+			n.Children[i] = makeTestLeafNode(small)
+		}
+	}
+	n.Children[16] = testrand.Bytes(32) // value
+	buf := rlp.NewEncoderBuffer(nil)
+	n.encode(buf)
+	return buf.ToBytes()
+}
+
+func TestEncodeDecodeNodeElements(t *testing.T) {
+	var nodes [][]byte
+	nodes = append(nodes, makeTestFullNode(true))
+	nodes = append(nodes, makeTestFullNode(false))
+	nodes = append(nodes, makeTestLeafNode(true))
+	nodes = append(nodes, makeTestLeafNode(false))
+
+	for _, blob := range nodes {
+		elements, err := decodeNodeElements(blob)
+		if err != nil {
+			t.Fatalf("Failed to decode node elements: %v", err)
+		}
+		enc, err := encodeNodeElements(elements)
+		if err != nil {
+			t.Fatalf("Failed to encode node elements: %v", err)
+		}
+		if !bytes.Equal(enc, blob) {
+			t.Fatalf("Unexpected encoded node element, want: %v, got: %v", blob, enc)
+		}
+	}
+}
+
+func makeTestLeafNodePair() ([]byte, []byte, [][]byte, []int) {
+	var (
+		na = leafNodeEncoder{}
+		nb = leafNodeEncoder{}
+	)
+	key := keybytesToHex(testrand.Bytes(10))
+	na.Key = hexToCompact(key)
+	nb.Key = hexToCompact(key)
+
+	valA := testrand.Bytes(32)
+	valB := testrand.Bytes(32)
+	na.Val = valA
+	nb.Val = valB
+
+	bufa, bufb := rlp.NewEncoderBuffer(nil), rlp.NewEncoderBuffer(nil)
+	na.encode(bufa)
+	nb.encode(bufb)
+	diff, _ := rlp.EncodeToBytes(valA)
+	return bufa.ToBytes(), bufb.ToBytes(), [][]byte{diff}, []int{1}
+}
+
+func makeTestFullNodePair() ([]byte, []byte, [][]byte, []int) {
+	var (
+		na      = fullnodeEncoder{}
+		nb      = fullnodeEncoder{}
+		indices []int
+		values  [][]byte
+	)
+	for i := 0; i < 16; i++ {
+		switch rand.Intn(3) {
+		case 0:
+			// write nil
+		case 1:
+			// write same
+			var child []byte
+			if rand.Intn(2) == 0 {
+				child = testrand.Bytes(32) // hashnode
+			} else {
+				child = makeTestLeafNode(true) // embedded node
+			}
+			na.Children[i] = child
+			nb.Children[i] = child
+		case 2:
+			// write different
+			var (
+				va   []byte
+				diff []byte
+			)
+			rnd := rand.Intn(3)
+			if rnd == 0 {
+				va = testrand.Bytes(32) // hashnode
+				diff, _ = rlp.EncodeToBytes(va)
+			} else if rnd == 1 {
+				va = makeTestLeafNode(true) // embedded node
+				diff = va
+			} else {
+				va = nil
+				diff = rlp.EmptyString
+			}
+			vb := testrand.Bytes(32) // hashnode
+			na.Children[i] = va
+			nb.Children[i] = vb
+
+			indices = append(indices, i)
+			values = append(values, diff)
+		}
+	}
+	na.Children[16] = nil
+	nb.Children[16] = nil
+
+	bufa, bufb := rlp.NewEncoderBuffer(nil), rlp.NewEncoderBuffer(nil)
+	na.encode(bufa)
+	nb.encode(bufb)
+	return bufa.ToBytes(), bufb.ToBytes(), values, indices
+}
+
+func TestNodeDifference(t *testing.T) {
+	type testsuite struct {
+		old        []byte
+		new        []byte
+		expErr     bool
+		expIndices []int
+		expValues  [][]byte
+	}
+	var tests = []testsuite{
+		// Invalid node data
+		{
+			old: nil, new: nil, expErr: true,
+		},
+		{
+			old: testrand.Bytes(32), new: nil, expErr: true,
+		},
+		{
+			old: nil, new: testrand.Bytes(32), expErr: true,
+		},
+		{
+			old: testrand.Bytes(32), new: testrand.Bytes(32), expErr: true,
+		},
+		// Different node type
+		{
+			old: makeTestLeafNode(true), new: makeTestFullNode(true), expErr: true,
+		},
+	}
+	for range 10 {
+		va, vb, elements, indices := makeTestLeafNodePair()
+		tests = append(tests, testsuite{
+			old:        va,
+			new:        vb,
+			expErr:     false,
+			expIndices: indices,
+			expValues:  elements,
+		})
+	}
+	for range 10 {
+		va, vb, elements, indices := makeTestFullNodePair()
+		tests = append(tests, testsuite{
+			old:        va,
+			new:        vb,
+			expErr:     false,
+			expIndices: indices,
+			expValues:  elements,
+		})
+	}
+
+	for _, test := range tests {
+		_, indices, values, err := NodeDifference(test.old, test.new)
+		if test.expErr && err == nil {
+			t.Fatal("Expect error, got nil")
+		}
+		if !test.expErr && err != nil {
+			t.Fatalf("Unexpect error, %v", err)
+		}
+		if err == nil {
+			if !reflect.DeepEqual(indices, test.expIndices) {
+				t.Fatalf("Unexpected indices, want: %v, got: %v", test.expIndices, indices)
+			}
+			if !reflect.DeepEqual(values, test.expValues) {
+				t.Fatalf("Unexpected values, want: %v, got: %v", test.expValues, values)
+			}
+		}
+	}
+}
+
+func TestReassembleFullNode(t *testing.T) {
+	var fn fullnodeEncoder
+	for i := 0; i < 16; i++ {
+		if rand.Intn(2) == 0 {
+			fn.Children[i] = testrand.Bytes(32)
+		}
+	}
+	buf := rlp.NewEncoderBuffer(nil)
+	fn.encode(buf)
+	enc := buf.ToBytes()
+
+	// Generate a list of diffs
+	var (
+		values  [][][]byte
+		indices [][]int
+	)
+	for i := 0; i < 10; i++ {
+		var (
+			pos       = make(map[int]struct{})
+			poslist   []int
+			valuelist [][]byte
+		)
+		for j := 0; j < 3; j++ {
+			p := rand.Intn(16)
+			if _, ok := pos[p]; ok {
+				continue
+			}
+			pos[p] = struct{}{}
+
+			nh := testrand.Bytes(32)
+			diff, _ := rlp.EncodeToBytes(nh)
+			poslist = append(poslist, p)
+			valuelist = append(valuelist, diff)
+			fn.Children[p] = nh
+		}
+		values = append(values, valuelist)
+		indices = append(indices, poslist)
+	}
+	reassembled, err := ReassembleNode(enc, values, indices)
+	if err != nil {
+		t.Fatalf("Failed to re-assemble full node %v", err)
+	}
+	buf2 := rlp.NewEncoderBuffer(nil)
+	fn.encode(buf2)
+	enc2 := buf2.ToBytes()
+	if !reflect.DeepEqual(enc2, reassembled) {
+		t.Fatalf("Unexpeted reassembled node")
+	}
+}
+
+func TestReassembleShortNode(t *testing.T) {
+	var ln leafNodeEncoder
+	ln.Key = hexToCompact(keybytesToHex(testrand.Bytes(10)))
+	ln.Val = testrand.Bytes(10)
+	buf := rlp.NewEncoderBuffer(nil)
+	ln.encode(buf)
+	enc := buf.ToBytes()
+
+	// Generate a list of diffs
+	var (
+		values  [][][]byte
+		indices [][]int
+	)
+	for i := 0; i < 10; i++ {
+		val := testrand.Bytes(10)
+		ln.Val = val
+		diff, _ := rlp.EncodeToBytes(val)
+		values = append(values, [][]byte{diff})
+		indices = append(indices, []int{1})
+	}
+	reassembled, err := ReassembleNode(enc, values, indices)
+	if err != nil {
+		t.Fatalf("Failed to re-assemble full node %v", err)
+	}
+	buf2 := rlp.NewEncoderBuffer(nil)
+	ln.encode(buf2)
+	enc2 := buf2.ToBytes()
+	if !reflect.DeepEqual(enc2, reassembled) {
+		t.Fatalf("Unexpeted reassembled node")
+	}
+}
+
 // goos: darwin
 // goarch: arm64
 // pkg: github.com/ethereum/go-ethereum/trie

triedb/pathdb/nodes.go

@@ -14,12 +14,14 @@
 // You should have received a copy of the GNU Lesser General Public License
 // along with the go-ethereum library. If not, see <http://www.gnu.org/licenses/>.
 
+// nolint:unused
 package pathdb
 
 import (
 	"bytes"
 	"errors"
 	"fmt"
+	"hash/fnv"
 	"io"
 	"maps"
 
@@ -30,6 +32,7 @@ import (
 	"github.com/ethereum/go-ethereum/ethdb"
 	"github.com/ethereum/go-ethereum/log"
 	"github.com/ethereum/go-ethereum/rlp"
+	"github.com/ethereum/go-ethereum/trie"
 	"github.com/ethereum/go-ethereum/trie/trienode"
 )
 
@@ -424,3 +427,239 @@ func (s *nodeSetWithOrigin) decode(r *rlp.Stream) error {
 	s.computeSize()
 	return nil
 }
+
+// encodeNodeCompressed encodes the trie node differences between two consecutive
+// versions into byte stream. The format is as below:
+//
+// - metadata byte layout (1 byte):
+//
+//	┌──── Bits (from MSB to LSB) ───┐
+//	│ 7 │ 6 │ 5 │ 4 │ 3 │ 2 │ 1 │ 0 │
+//	└───────────────────────────────┘
+//	  │   │   │   │   │   │   │   └─ FlagA: marks if value is encoded in compressed format (1 always)
+//	  │   │   │   │   │   │   └───── FlagB: marks if no extended bitmap used after the metadata byte
+//	  │   │   │   │   │   └───────── FlagC: bitmap for node (only used when flagB == 1)
+//	  │   │   │   │   └───────────── FlagD: bitmap for node (only used when flagB == 1)
+//	  │   │   │   └───────────────── FlagE: reserved
+//	  │   │   └───────────────────── FlagF: reserved
+//	  │   └───────────────────────── FlagG: reserved
+//	  └───────────────────────────── FlagH: reserved
+//
+// Example:
+//
+// 0b_0000_1011
+//
+// Bit0=1, Bit1=1 -> node in compressed format, no extended bitmap
+// Bit2=0, Bit3=1 -> the key of a short node is not stored; its value is stored.
+//
+// - 2 bytes extended bitmap (only if the flagB in metadata is 0), each bit
+// represents a corresponding child;
+//
+// - concatenation of original value of modified children along with its size;
+func encodeNodeCompressed(addExtension bool, elements [][]byte, indices []int) []byte {
+	var (
+		enc  []byte
+		flag = byte(1) // flagA
+	)
+	if !addExtension {
+		flag |= 2 // flagB
+
+		// Embedded bitmap
+		for _, pos := range indices {
+			flag |= 1 << (pos + 2) // flagC and flagD
+		}
+		enc = append(enc, flag)
+	} else {
+		// Extended bitmap
+		bitmap := make([]byte, 2) // bitmaps for at most 16 children
+		for _, pos := range indices {
+			// Children[16] is only theoretically possible in the Merkle-Patricia-trie,
+			// in practice this field is never used in the Ethereum case.
+			if pos == 16 {
+				panic(fmt.Sprintf("Unexpected node children index %d", pos))
+			}
+			bitIndex := uint(pos % 8)
+			bitmap[pos/8] |= 1 << bitIndex
+		}
+		enc = append(enc, flag)
+		enc = append(enc, bitmap...)
+	}
+	for _, element := range elements {
+		enc = append(enc, byte(len(element))) // 1 byte is sufficient for element size
+		enc = append(enc, element...)
+	}
+	return enc
+}
+
+// encodeNodeFull encodes the full trie node value into byte stream. The format is
+// as below:
+//
+// - metadata byte layout (1 byte): 0b0
+// - node value
+func encodeNodeFull(value []byte) []byte {
+	enc := make([]byte, len(value)+1)
+	copy(enc[1:], value)
+	return enc
+}
+
+// decodeNodeCompressed decodes the byte stream of compressed trie node
+// back to the original elements and their indices.
+//
+// It assumes the byte stream contains a compressed format node.
+func decodeNodeCompressed(data []byte) ([][]byte, []int, error) {
+	if len(data) < 1 {
+		return nil, nil, errors.New("invalid data: too short")
+	}
+	flag := data[0]
+	if flag&byte(1) == 0 {
+		return nil, nil, errors.New("invalid data: full node value")
+	}
+	noExtend := flag&byte(2) != 0 // flagB
+
+	// Reconstruct indices from bitmap
+	var indices []int
+	if noExtend {
+		if flag&byte(4) != 0 { // flagC
+			indices = append(indices, 0)
+		}
+		if flag&byte(8) != 0 { // flagD
+			indices = append(indices, 1)
+		}
+		data = data[1:]
+	} else {
+		if len(data) < 3 {
+			return nil, nil, errors.New("invalid data: too short")
+		}
+		bitmap := data[1:3]
+		for index, b := range bitmap {
+			for bitIdx := 0; bitIdx < 8; bitIdx++ {
+				if b&(1<<uint(bitIdx)) != 0 {
+					pos := index*8 + bitIdx
+					indices = append(indices, pos)
+				}
+			}
+		}
+		data = data[3:]
+	}
+	// Reconstruct elements
+	elements := make([][]byte, 0, len(indices))
+	for i := 0; i < len(indices); i++ {
+		if len(data) == 0 {
+			return nil, nil, errors.New("invalid data: missing size byte")
+		}
+		// Read element size
+		size := int(data[0])
+		data = data[1:]
+
+		// Check if we have enough data for the element
+		if len(data) < size {
+			return nil, nil, fmt.Errorf("invalid data: expected %d bytes, got %d", size, len(data))
+		}
+		// Extract element
+		if size == 0 {
+			elements = append(elements, nil)
+
+			// The zero-size element is practically unexpected, for node deletion
+			// the rlp.EmptyString is still expected. Log loudly for the potential
+			// programming error.
+			log.Warn("Empty element from compressed node", "raw", data)
+		} else {
+			element := make([]byte, size)
+			copy(element, data[:size])
+			data = data[size:]
+			elements = append(elements, element)
+		}
+	}
+	// Check if all data is consumed
+	if len(data) != 0 {
+		return nil, nil, errors.New("invalid data: trailing bytes")
+	}
+	return elements, indices, nil
+}
+
+// decodeNodeFull decodes the byte stream of full value trie node.
+func decodeNodeFull(data []byte) ([]byte, error) {
+	if len(data) < 1 {
+		return nil, errors.New("invalid data: too short")
+	}
+	flag := data[0]
+	if flag != byte(0) {
+		return nil, errors.New("invalid data: compressed node value")
+	}
+	return data[1:], nil
+}
+
+// encodeFullFrequency specifies the frequency (1/16) for encoding node in
+// full format. TODO(rjl493456442) making it configurable.
+const encodeFullFrequency = 16
+
+// encodeNodeHistory encodes the history of a node. Typically, the original values
+// of dirty nodes serve as the history, but this can lead to significant storage
+// overhead.
+//
+// For full nodes, which often see only a few modified children during state
+// transitions, recording the entire child set (up to 16 children at 32 bytes
+// each) is inefficient. For short nodes, which often see only the value is
+// modified during the state transition, recording the key part is also unnecessary.
+// To compress size, we instead record the diff of the node, rather than the
+// full value. It's vital to compress the overall trienode history.
+//
+// However, recovering a node from a series of diffs requires applying multiple
+// history records, which is computationally and IO intensive. To mitigate this, we
+// periodically record the full value of a node as a checkpoint. The frequency of
+// these checkpoints is a tradeoff between the compression rate and read overhead.
+func (s *nodeSetWithOrigin) encodeNodeHistory(root common.Hash) (map[common.Hash]map[string][]byte, error) {
+	var (
+		// the set of all encoded node history elements
+		nodes = make(map[common.Hash]map[string][]byte)
+
+		// encodeFullValue determines whether a node should be encoded
+		// in full format with a pseudo-random probabilistic algorithm.
+		encodeFullValue = func(owner common.Hash, path string) bool {
+			h := fnv.New32a()
+			h.Write(root.Bytes())
+			h.Write(owner.Bytes())
+			h.Write([]byte(path))
+			return h.Sum32()%uint32(encodeFullFrequency) == 0
+		}
+	)
+	for owner, origins := range s.nodeOrigin {
+		var posts map[string]*trienode.Node
+		if owner == (common.Hash{}) {
+			posts = s.nodeSet.accountNodes
+		} else {
+			posts = s.nodeSet.storageNodes[owner]
+		}
+		nodes[owner] = make(map[string][]byte)
+
+		for path, oldvalue := range origins {
+			n, exists := posts[path]
+			if !exists {
+				// something not expected
+				return nil, fmt.Errorf("node with origin is not found, %x-%v", owner, []byte(path))
+			}
+			encodeFull := encodeFullValue(owner, path)
+			if !encodeFull {
+				// Partial encoding is required, try to find the node diffs and
+				// fallback to the full-value encoding if fails.
+				//
+				// The partial encoding will be failed in these certain cases:
+				// - the node is deleted or was not-existent;
+				// - the node type has been changed (e.g, from short to full)
+				nElem, indices, diffs, err := trie.NodeDifference(oldvalue, n.Blob)
+				if err != nil {
+					encodeFull = true // fallback to the full node encoding
+				} else {
+					// Encode the node difference as the history element
+					blob := encodeNodeCompressed(nElem == 2, diffs, indices)
+					nodes[owner][path] = blob
+				}
+			}
+			if encodeFull {
+				// Encode the entire original value as the history element
+				nodes[owner][path] = encodeNodeFull(oldvalue)
+			}
+		}
+	}
+	return nodes, nil
+}

triedb/pathdb/nodes_test.go

@@ -18,11 +18,13 @@ package pathdb
 
 import (
 	"bytes"
+	"math/rand"
 	"reflect"
 	"testing"
 
 	"github.com/ethereum/go-ethereum/common"
 	"github.com/ethereum/go-ethereum/crypto"
+	"github.com/ethereum/go-ethereum/internal/testrand"
 	"github.com/ethereum/go-ethereum/rlp"
 	"github.com/ethereum/go-ethereum/trie/trienode"
 )
@@ -126,3 +128,49 @@ func TestNodeSetWithOriginEncode(t *testing.T) {
 		t.Fatalf("Unexpected data size, got: %d, want: %d", dec2.size, s.size)
 	}
 }
+
+func TestEncodeFullNodeCompressed(t *testing.T) {
+	var (
+		elements [][]byte
+		indices  []int
+	)
+	for i := 0; i < 16; i++ {
+		if rand.Intn(2) == 0 {
+			elements = append(elements, testrand.Bytes(20))
+			indices = append(indices, i)
+		}
+	}
+	enc := encodeNodeCompressed(true, elements, indices)
+	decElements, decIndices, err := decodeNodeCompressed(enc)
+	if err != nil {
+		t.Fatalf("Failed to decode node compressed, %v", err)
+	}
+	if !reflect.DeepEqual(elements, decElements) {
+		t.Fatalf("Elements are not matched")
+	}
+	if !reflect.DeepEqual(indices, decIndices) {
+		t.Fatalf("Indices are not matched")
+	}
+}
+
+func TestEncodeShortNodeCompressed(t *testing.T) {
+	var (
+		elements [][]byte
+		indices  []int
+	)
+	for i := 0; i < 2; i++ {
+		elements = append(elements, testrand.Bytes(20))
+		indices = append(indices, i)
+	}
+	enc := encodeNodeCompressed(false, elements, indices)
+	decElements, decIndices, err := decodeNodeCompressed(enc)
+	if err != nil {
+		t.Fatalf("Failed to decode node compressed, %v", err)
+	}
+	if !reflect.DeepEqual(elements, decElements) {
+		t.Fatalf("Elements are not matched")
+	}
+	if !reflect.DeepEqual(indices, decIndices) {
+		t.Fatalf("Indices are not matched")
+	}
+}