eth/downloader: add a basic block download congestion control

eth/downloader/queue_test.go

@@ -1,8 +1,6 @@
 package downloader
 
 import (
-	"testing"
-
 	"github.com/ethereum/go-ethereum/common"
 	"github.com/ethereum/go-ethereum/core/types"
 	"gopkg.in/fatih/set.v0"
@@ -30,32 +28,3 @@ func createBlocksFromHashSet(hashes *set.Set) []*types.Block {
 
 	return blocks
 }
-
-func TestChunking(t *testing.T) {
-	queue := newQueue()
-	peer1 := newPeer("peer1", common.Hash{}, nil, nil)
-	peer2 := newPeer("peer2", common.Hash{}, nil, nil)
-
-	// 99 + 1 (1 == known genesis hash)
-	hashes := createHashes(0, 99)
-	queue.Insert(hashes)
-
-	chunk1 := queue.Reserve(peer1, 99)
-	if chunk1 == nil {
-		t.Errorf("chunk1 is nil")
-		t.FailNow()
-	}
-	chunk2 := queue.Reserve(peer2, 99)
-	if chunk2 == nil {
-		t.Errorf("chunk2 is nil")
-		t.FailNow()
-	}
-
-	if len(chunk1.Hashes) != 99 {
-		t.Error("expected chunk1 hashes to be 99, got", len(chunk1.Hashes))
-	}
-
-	if len(chunk2.Hashes) != 1 {
-		t.Error("expected chunk1 hashes to be 1, got", len(chunk2.Hashes))
-	}
-}