core, eth/downloader: fix ancestor lookup for fast sync

eth/downloader/downloader_test.go

@@ -115,6 +115,15 @@ func (dl *downloadTester) HasBlock(hash common.Hash, number uint64) bool {
 	return dl.GetBlockByHash(hash) != nil
 }
 
+// HasFastBlock checks if a block is present in the testers canonical chain.
+func (dl *downloadTester) HasFastBlock(hash common.Hash, number uint64) bool {
+	dl.lock.RLock()
+	defer dl.lock.RUnlock()
+
+	_, ok := dl.ownReceipts[hash]
+	return ok
+}
+
 // GetHeader retrieves a header from the testers canonical chain.
 func (dl *downloadTester) GetHeaderByHash(hash common.Hash) *types.Header {
 	dl.lock.RLock()
@@ -235,6 +244,7 @@ func (dl *downloadTester) InsertChain(blocks types.Blocks) (i int, err error) {
 			dl.ownHeaders[block.Hash()] = block.Header()
 		}
 		dl.ownBlocks[block.Hash()] = block
+		dl.ownReceipts[block.Hash()] = make(types.Receipts, 0)
 		dl.stateDb.Put(block.Root().Bytes(), []byte{0x00})
 		dl.ownChainTd[block.Hash()] = new(big.Int).Add(dl.ownChainTd[block.ParentHash()], block.Difficulty())
 	}
@@ -375,28 +385,28 @@ func (dlp *downloadTesterPeer) RequestNodeData(hashes []common.Hash) error {
 // assertOwnChain checks if the local chain contains the correct number of items
 // of the various chain components.
 func assertOwnChain(t *testing.T, tester *downloadTester, length int) {
+	// Mark this method as a helper to report errors at callsite, not in here
+	t.Helper()
+
 	assertOwnForkedChain(t, tester, 1, []int{length})
 }
 
 // assertOwnForkedChain checks if the local forked chain contains the correct
 // number of items of the various chain components.
 func assertOwnForkedChain(t *testing.T, tester *downloadTester, common int, lengths []int) {
-	// Initialize the counters for the first fork
-	headers, blocks, receipts := lengths[0], lengths[0], lengths[0]-fsMinFullBlocks
+	// Mark this method as a helper to report errors at callsite, not in here
+	t.Helper()
+
+	// Initialize the counters for the first fork
+	headers, blocks, receipts := lengths[0], lengths[0], lengths[0]
 
-	if receipts < 0 {
-		receipts = 1
-	}
 	// Update the counters for each subsequent fork
 	for _, length := range lengths[1:] {
 		headers += length - common
 		blocks += length - common
-		receipts += length - common - fsMinFullBlocks
+		receipts += length - common
 	}
-	switch tester.downloader.mode {
-	case FullSync:
-		receipts = 1
-	case LightSync:
+	if tester.downloader.mode == LightSync {
 		blocks, receipts = 1, 1
 	}
 	if hs := len(tester.ownHeaders); hs != headers {
@@ -1150,7 +1160,9 @@ func testSyncProgress(t *testing.T, protocol int, mode SyncMode) {
 }
 
 func checkProgress(t *testing.T, d *Downloader, stage string, want ethereum.SyncProgress) {
+	// Mark this method as a helper to report errors at callsite, not in here
 	t.Helper()
+
 	p := d.Progress()
 	p.KnownStates, p.PulledStates = 0, 0
 	want.KnownStates, want.PulledStates = 0, 0