chore: polish comments

cmd/devp2p/internal/ethtest/suite.go

@@ -81,7 +81,7 @@ func (s *Suite) EthTests() []utesting.Test {
 		{Name: "ZeroRequestID", Fn: s.TestZeroRequestID},
 		// get history
 		{Name: "GetBlockBodies", Fn: s.TestGetBlockBodies},
-		{Name: "GetReceipts70", Fn: s.TestGetReceipts},
+		{Name: "GetReceipts", Fn: s.TestGetReceipts},
 		// test transactions
 		{Name: "LargeTxRequest", Fn: s.TestLargeTxRequest, Slow: true},
 		{Name: "Transaction", Fn: s.TestTransaction},

eth/downloader/queue.go

@@ -679,7 +679,7 @@ func (q *queue) deliver(id string, taskPool map[common.Hash]*types.Header,
 	// If no data items were retrieved, mark them as unavailable for the origin peer
 	if results == 0 {
 		for _, header := range request.Headers {
-			request.Peer.MarkLacking(header.Hash()) //todo?
+			request.Peer.MarkLacking(header.Hash())
 		}
 	}
 	// Assemble each of the results with their headers and retrieved data parts
@@ -720,7 +720,6 @@ func (q *queue) deliver(id string, taskPool map[common.Hash]*types.Header,
 	resDropMeter.Mark(int64(results - accepted))
 
 	// Return all failed or missing fetches to the queue
-	//todo
 	if incomplete {
 		for _, header := range request.Headers[from+accepted : from+results] {
 			taskQueue.Push(header, -int64(header.Number.Uint64()))

eth/downloader/queue_test.go

@@ -274,9 +274,9 @@ func TestEmptyBlocks(t *testing.T) {
 	}
 }
 
-// TestPartialReceiptDelivery checks two points below
-// 1. Receipts failed validation should be re requested to the other peers
-// 2. Partial delivery should not be expired
+// TestPartialReceiptDelivery checks two points:
+// 1. Receipts that fail validation should be re-requested from other peers.
+// 2. Partial delivery should not expire.
 func TestPartialReceiptDelivery(t *testing.T) {
 	blocks, receipts := makeChain(64, 0, testGenesis, blockConfig{txPeriod: 1, txCount: 5})
 	chain := chainData{blocks: blocks, receipts: receipts, offset: 0}
@@ -305,7 +305,7 @@ func TestPartialReceiptDelivery(t *testing.T) {
 
 	t.Logf("request: length %d", len(req.Headers))
 
-	// 1. Deliver partial receipt: should not clear the remaining receipts from pending list
+	// 1. Deliver a partial receipt: this must not clear the remaining receipts from the pending list
 	firstCutoff := len(req.Headers) / 3
 	receiptRLP, rcHashes := getPartialReceiptsDelivery(0, firstCutoff, receipts)
 	accepted, err := q.DeliverReceipts(peer.id, receiptRLP, rcHashes, true, 0)
@@ -333,7 +333,7 @@ func TestPartialReceiptDelivery(t *testing.T) {
 		t.Fatalf("there should be in flight receipts")
 	}
 
-	// 2. Deliver partial receipt with invalid receipt: should clear invalid receipt from pending list
+	// 2. Deliver a partial receipt containing an invalid entry: the invalid receipt should be removed from the pending list
 	secondCutoff := firstCutoff + len(req.Headers)/3
 	receiptRLP, rcHashes = getPartialReceiptsDelivery(firstCutoff, secondCutoff, receipts)
 	// one invalid receipt
@@ -346,7 +346,7 @@ func TestPartialReceiptDelivery(t *testing.T) {
 		t.Fatalf("delivery should fail")
 	}
 
-	// invalid receipt should returned back to the pending pool
+	// The invalid receipt should be returned to the pending pool
 	if pending := q.PendingReceipts(); pending != numBlock-len(req.Headers)+1 {
 		t.Fatalf("wrong pending receipt length, got %d, exp %d", pending, numBlock-len(req.Headers))
 	}
@@ -364,7 +364,7 @@ func TestPartialReceiptDelivery(t *testing.T) {
 		}
 	}
 
-	// 3. Deliver partial receipt to complete request
+	// 3. Deliver the remaining receipts to complete the request
 	thirdCutoff := len(req.Headers)
 	receiptRLP, rcHashes = getPartialReceiptsDelivery(secondCutoff, thirdCutoff, receipts)
 	accepted, err = q.DeliverReceipts(peer.id, receiptRLP, rcHashes, false, secondCutoff)

eth/protocols/eth/handler_test.go

@@ -553,7 +553,7 @@ func testGetBlockReceipts(t *testing.T, protocol uint) {
 func TestGetBlockPartialReceipts(t *testing.T) { testGetBlockPartialReceipts(t, ETH70) }
 
 func testGetBlockPartialReceipts(t *testing.T, protocol int) {
-	// First generate chain and overwrite receipts
+	// First, generate the chain and overwrite the receipts.
 	generator := func(_ int, block *core.BlockGen) {
 		for j := 0; j < 5; j++ {
 			tx, err := types.SignTx(
@@ -573,7 +573,7 @@ func testGetBlockPartialReceipts(t *testing.T, protocol int) {
 	blockCutoff := 2
 	receiptCutoff := 4
 
-	// Replace receipts in DB with larger receipts
+	// Replace the receipts in the database with larger receipts.
 	targetBlock := backend.chain.GetBlockByNumber(uint64(blockCutoff))
 	receipts := backend.chain.GetReceiptsByHash(targetBlock.Hash())
 	receiptSize := params.MaxTxGas / params.LogDataGas // ~2MiB per receipt
@@ -626,7 +626,7 @@ func testGetBlockPartialReceipts(t *testing.T, protocol int) {
 		t.Errorf("receipts mismatch: %v", err)
 	}
 
-	// Simulate re-request
+	// Simulate the continued request
 	partialReceipt = []*ReceiptList69{NewReceiptList69(receipts[receiptCutoff:])}
 
 	p2p.Send(peer.app, GetReceiptsMsg, &GetReceiptsPacket70{

eth/protocols/eth/handlers.go

@@ -353,8 +353,8 @@ func serviceGetReceiptsQuery69(chain *core.BlockChain, query GetReceiptsRequest)
 }
 
 // serviceGetReceiptsQuery70 assembles the response to a receipt query.
-// If the size of receipts is larger than 10MB, it would cut it and flag lastBlockIncomplete
-// It omits up to firstBlockReceiptIndex receipt from the first receipt list
+// If the receipts exceed 10 MiB, it trims them and sets the lastBlockIncomplete flag.
+// Indices smaller than firstBlockReceiptIndex are omitted from the first block receipt list.
 func serviceGetReceiptsQuery70(chain *core.BlockChain, query GetReceiptsRequest, firstBlockReceiptIndex uint64) ([]rlp.RawValue, bool) {
 	var (
 		bytes               int

eth/protocols/eth/peer.go

@@ -363,7 +363,7 @@ func (p *Peer) RequestReceipts(hashes []common.Hash, sink chan *Response) (*Requ
 	return req, nil
 }
 
-// handlePartialReceipts re-request partial receipts
+// HandlePartialReceipts re-request partial receipts
 func (p *Peer) HandlePartialReceipts(previousId uint64) error {
 	split := p.receiptBuffer[previousId].idx
 	id := rand.Uint64()
@@ -385,8 +385,8 @@ func (p *Peer) HandlePartialReceipts(previousId uint64) error {
 	return p.dispatchRequest(req)
 }
 
-// validateReceipt validate and check completion of partial request
-// This function also modifies packet (trim partial response or append previously collected receipts)
+// ValidateReceipt validates a receipt packet and checks whether a partial request is complete.
+// It also mutates the packet in place, trimming the partial response or appending previously collected receipts.
 func (p *Peer) ValidateReceipt(packet *ReceiptsPacket70) (int, error) {
 	from := 0
 	requestId := packet.RequestId
@@ -394,8 +394,8 @@ func (p *Peer) ValidateReceipt(packet *ReceiptsPacket70) (int, error) {
 		return 0, fmt.Errorf("receipt list size 0")
 	}
 
-	// process first block
-	// : partially collected before and completed by this response
+	// Process the first block
+	// If the request was partially collected earlier, append the buffered data so this response completes it.
 	firstReceipt := packet.List[0]
 	if firstReceipt == nil {
 		return 0, fmt.Errorf("nil first receipt")
@@ -407,7 +407,7 @@ func (p *Peer) ValidateReceipt(packet *ReceiptsPacket70) (int, error) {
 		delete(p.receiptBuffer, requestId)
 	}
 
-	// process last block
+	// Trim and buffer the last block when the response is incomplete.
 	if packet.LastBlockIncomplete {
 		lastReceipts := packet.List[len(packet.List)-1]
 		if lastReceipts == nil {
@@ -421,25 +421,25 @@ func (p *Peer) ValidateReceipt(packet *ReceiptsPacket70) (int, error) {
 			previousLog = buffer.size
 		}
 
-		// 1. Verify the total number of tx delivered
+		// 1. Verify that the total number of transactions delivered is under the limit.
 		if uint64(previousTxs+len(lastReceipts.items)) > lastReceipts.items[0].GasUsed/21_000 {
 			// should be dropped, don't clear the buffer
 			return 0, fmt.Errorf("total number of tx exceeded limit")
 		}
 
-		// 2. Verify the size of each receipt against the gas limit of the corresponding transaction
+		// 2. Verify the size of each receipt against the maximum transaction size.
 		for _, rc := range lastReceipts.items {
 			if uint64(len(rc.Logs)) > params.MaxTxGas/params.LogDataGas {
 				return 0, fmt.Errorf("total size of receipt exceeded limit")
 			}
 			previousLog += uint64(len(rc.Logs))
 		}
-		// 3. Verify the total download receipt size is no longer than allowed by the block gas limit
+		// 3. Verify that the overall downloaded receipt size does not exceed the block gas limit.
 		if previousLog > params.MaxGasLimit/params.LogDataGas {
 			return 0, fmt.Errorf("total download receipt size exceeded the limit")
 		}
 
-		// Update buffer & trim packet
+		// Update the buffered data and trim the packet to exclude the incomplete block.
 		if buffer, ok := p.receiptBuffer[requestId]; ok {
 			buffer.idx = buffer.idx + len(packet.List) - 1
 			buffer.list.items = append(buffer.list.items, lastReceipts.items...)