From a080dcf356ec5e8b135863ed11f5ca37f7d488ad Mon Sep 17 00:00:00 2001
From: rjl493456442 <garyrong0905@gmail.com>
Date: Wed, 9 May 2018 19:18:25 +0800
Subject: [PATCH] all: inline mdb definition

---
 cmd/evm/runner.go                |  3 +-
 core/helper_test.go              |  5 +--
 core/state/managed_state_test.go |  3 +-
 core/state/state_test.go         |  3 +-
 core/state/statedb_test.go       |  9 ++----
 core/state/sync_test.go          |  6 ++--
 core/tx_pool_test.go             | 54 +++++++++++---------------------
 core/vm/runtime/runtime.go       |  6 ++--
 core/vm/runtime/runtime_test.go  |  3 +-
 eth/api_test.go                  |  3 +-
 eth/tracers/tracers_test.go      |  3 +-
 ethdb/database_test.go           |  6 ++--
 les/handler_test.go              |  9 ++----
 tests/state_test_util.go         |  3 +-
 tests/vm_test_util.go            |  3 +-
 trie/secure_trie_test.go         |  8 ++---
 trie/sync_test.go                | 18 ++++-------
 trie/trie_test.go                |  9 ++----
 18 files changed, 50 insertions(+), 104 deletions(-)

diff --git a/cmd/evm/runner.go b/cmd/evm/runner.go
index ef1a96f6dbea..7138a9ddd439 100644
--- a/cmd/evm/runner.go
+++ b/cmd/evm/runner.go
@@ -104,8 +104,7 @@ func runCmd(ctx *cli.Context) error {
 		chainConfig = gen.Config
 		blockNumber = gen.Number
 	} else {
-		db := ethdb.NewMemDatabase()
-		statedb, _ = state.New(common.Hash{}, state.NewDatabase(db))
+		statedb, _ = state.New(common.Hash{}, state.NewDatabase(ethdb.NewMemDatabase()))
 	}
 	if ctx.GlobalString(SenderFlag.Name) != "" {
 		sender = common.HexToAddress(ctx.GlobalString(SenderFlag.Name))
diff --git a/core/helper_test.go b/core/helper_test.go
index 00e67de2778e..051384d8547b 100644
--- a/core/helper_test.go
+++ b/core/helper_test.go
@@ -76,14 +76,11 @@ func (tm *TestManager) Db() ethdb.Database {
 }
 
 func NewTestManager() *TestManager {
-	db := ethdb.NewMemDatabase()
-
 	testManager := &TestManager{}
 	testManager.eventMux = new(event.TypeMux)
-	testManager.db = db
+	testManager.db = ethdb.NewMemDatabase()
 	// testManager.txPool = NewTxPool(testManager)
 	// testManager.blockChain = NewBlockChain(testManager)
 	// testManager.stateManager = NewStateManager(testManager)
-
 	return testManager
 }
diff --git a/core/state/managed_state_test.go b/core/state/managed_state_test.go
index ebe796bc0185..3d9c4e867603 100644
--- a/core/state/managed_state_test.go
+++ b/core/state/managed_state_test.go
@@ -26,8 +26,7 @@ import (
 var addr = common.BytesToAddress([]byte("test"))
 
 func create() (*ManagedState, *account) {
-	db := ethdb.NewMemDatabase()
-	statedb, _ := New(common.Hash{}, NewDatabase(db))
+	statedb, _ := New(common.Hash{}, NewDatabase(ethdb.NewMemDatabase()))
 	ms := ManageState(statedb)
 	ms.StateDB.SetNonce(addr, 100)
 	ms.accounts[addr] = newAccount(ms.StateDB.getStateObject(addr))
diff --git a/core/state/state_test.go b/core/state/state_test.go
index 8c7412c1ceba..12778f6f129d 100644
--- a/core/state/state_test.go
+++ b/core/state/state_test.go
@@ -133,8 +133,7 @@ func (s *StateSuite) TestSnapshotEmpty(c *checker.C) {
 // use testing instead of checker because checker does not support
 // printing/logging in tests (-check.vv does not work)
 func TestSnapshot2(t *testing.T) {
-	db := ethdb.NewMemDatabase()
-	state, _ := New(common.Hash{}, NewDatabase(db))
+	state, _ := New(common.Hash{}, NewDatabase(ethdb.NewMemDatabase()))
 
 	stateobjaddr0 := toAddr([]byte("so0"))
 	stateobjaddr1 := toAddr([]byte("so1"))
diff --git a/core/state/statedb_test.go b/core/state/statedb_test.go
index 9a103aa3c18c..e2b349de86c1 100644
--- a/core/state/statedb_test.go
+++ b/core/state/statedb_test.go
@@ -122,8 +122,7 @@ func TestIntermediateLeaks(t *testing.T) {
 // https://github.com/ethereum/go-ethereum/pull/15549.
 func TestCopy(t *testing.T) {
 	// Create a random state test to copy and modify "independently"
-	db := ethdb.NewMemDatabase()
-	orig, _ := New(common.Hash{}, NewDatabase(db))
+	orig, _ := New(common.Hash{}, NewDatabase(ethdb.NewMemDatabase()))
 
 	for i := byte(0); i < 255; i++ {
 		obj := orig.GetOrNewStateObject(common.BytesToAddress([]byte{i}))
@@ -334,8 +333,7 @@ func (test *snapshotTest) String() string {
 func (test *snapshotTest) run() bool {
 	// Run all actions and create snapshots.
 	var (
-		db           = ethdb.NewMemDatabase()
-		state, _     = New(common.Hash{}, NewDatabase(db))
+		state, _     = New(common.Hash{}, NewDatabase(ethdb.NewMemDatabase()))
 		snapshotRevs = make([]int, len(test.snapshots))
 		sindex       = 0
 	)
@@ -426,8 +424,7 @@ func (s *StateSuite) TestTouchDelete(c *check.C) {
 // TestCopyOfCopy tests that modified objects are carried over to the copy, and the copy of the copy.
 // See https://github.com/ethereum/go-ethereum/pull/15225#issuecomment-380191512
 func TestCopyOfCopy(t *testing.T) {
-	db := ethdb.NewMemDatabase()
-	sdb, _ := New(common.Hash{}, NewDatabase(db))
+	sdb, _ := New(common.Hash{}, NewDatabase(ethdb.NewMemDatabase()))
 	addr := common.HexToAddress("aaaa")
 	sdb.SetBalance(addr, big.NewInt(42))
 
diff --git a/core/state/sync_test.go b/core/state/sync_test.go
index 6ec26d233444..31774016082a 100644
--- a/core/state/sync_test.go
+++ b/core/state/sync_test.go
@@ -38,8 +38,7 @@ type testAccount struct {
 // makeTestState create a sample test state to test node-wise reconstruction.
 func makeTestState() (Database, common.Hash, []*testAccount) {
 	// Create an empty state
-	diskdb := ethdb.NewMemDatabase()
-	db := NewDatabase(diskdb)
+	db := NewDatabase(ethdb.NewMemDatabase())
 	state, _ := New(common.Hash{}, db)
 
 	// Fill it with some arbitrary data
@@ -125,8 +124,7 @@ func checkStateConsistency(db ethdb.Database, root common.Hash) error {
 // Tests that an empty state is not scheduled for syncing.
 func TestEmptyStateSync(t *testing.T) {
 	empty := common.HexToHash("56e81f171bcc55a6ff8345e692c0f86e5b48e01b996cadc001622fb5e363b421")
-	db := ethdb.NewMemDatabase()
-	if req := NewStateSync(empty, db).Missing(1); len(req) != 0 {
+	if req := NewStateSync(empty, ethdb.NewMemDatabase()).Missing(1); len(req) != 0 {
 		t.Errorf("content requested for empty state: %v", req)
 	}
 }
diff --git a/core/tx_pool_test.go b/core/tx_pool_test.go
index 48104164730a..e7f52075e556 100644
--- a/core/tx_pool_test.go
+++ b/core/tx_pool_test.go
@@ -78,8 +78,7 @@ func pricedTransaction(nonce uint64, gaslimit uint64, gasprice *big.Int, key *ec
 }
 
 func setupTxPool() (*TxPool, *ecdsa.PrivateKey) {
-	diskdb := ethdb.NewMemDatabase()
-	statedb, _ := state.New(common.Hash{}, state.NewDatabase(diskdb))
+	statedb, _ := state.New(common.Hash{}, state.NewDatabase(ethdb.NewMemDatabase()))
 	blockchain := &testBlockChain{statedb, 1000000, new(event.Feed)}
 
 	key, _ := crypto.GenerateKey()
@@ -158,8 +157,7 @@ func (c *testChain) State() (*state.StateDB, error) {
 	// a state change between those fetches.
 	stdb := c.statedb
 	if *c.trigger {
-		db := ethdb.NewMemDatabase()
-		c.statedb, _ = state.New(common.Hash{}, state.NewDatabase(db))
+		c.statedb, _ = state.New(common.Hash{}, state.NewDatabase(ethdb.NewMemDatabase()))
 		// simulate that the new head block included tx0 and tx1
 		c.statedb.SetNonce(c.address, 2)
 		c.statedb.SetBalance(c.address, new(big.Int).SetUint64(params.Ether))
@@ -175,10 +173,9 @@ func TestStateChangeDuringTransactionPoolReset(t *testing.T) {
 	t.Parallel()
 
 	var (
-		db         = ethdb.NewMemDatabase()
 		key, _     = crypto.GenerateKey()
 		address    = crypto.PubkeyToAddress(key.PublicKey)
-		statedb, _ = state.New(common.Hash{}, state.NewDatabase(db))
+		statedb, _ = state.New(common.Hash{}, state.NewDatabase(ethdb.NewMemDatabase()))
 		trigger    = false
 	)
 
@@ -332,8 +329,7 @@ func TestTransactionChainFork(t *testing.T) {
 
 	addr := crypto.PubkeyToAddress(key.PublicKey)
 	resetState := func() {
-		db := ethdb.NewMemDatabase()
-		statedb, _ := state.New(common.Hash{}, state.NewDatabase(db))
+		statedb, _ := state.New(common.Hash{}, state.NewDatabase(ethdb.NewMemDatabase()))
 		statedb.AddBalance(addr, big.NewInt(100000000000000))
 
 		pool.chain = &testBlockChain{statedb, 1000000, new(event.Feed)}
@@ -362,8 +358,7 @@ func TestTransactionDoubleNonce(t *testing.T) {
 
 	addr := crypto.PubkeyToAddress(key.PublicKey)
 	resetState := func() {
-		db := ethdb.NewMemDatabase()
-		statedb, _ := state.New(common.Hash{}, state.NewDatabase(db))
+		statedb, _ := state.New(common.Hash{}, state.NewDatabase(ethdb.NewMemDatabase()))
 		statedb.AddBalance(addr, big.NewInt(100000000000000))
 
 		pool.chain = &testBlockChain{statedb, 1000000, new(event.Feed)}
@@ -553,8 +548,7 @@ func TestTransactionPostponing(t *testing.T) {
 	t.Parallel()
 
 	// Create the pool to test the postponing with
-	db := ethdb.NewMemDatabase()
-	statedb, _ := state.New(common.Hash{}, state.NewDatabase(db))
+	statedb, _ := state.New(common.Hash{}, state.NewDatabase(ethdb.NewMemDatabase()))
 	blockchain := &testBlockChain{statedb, 1000000, new(event.Feed)}
 
 	pool := NewTxPool(testTxPoolConfig, params.TestChainConfig, blockchain)
@@ -769,8 +763,7 @@ func testTransactionQueueGlobalLimiting(t *testing.T, nolocals bool) {
 	t.Parallel()
 
 	// Create the pool to test the limit enforcement with
-	db := ethdb.NewMemDatabase()
-	statedb, _ := state.New(common.Hash{}, state.NewDatabase(db))
+	statedb, _ := state.New(common.Hash{}, state.NewDatabase(ethdb.NewMemDatabase()))
 	blockchain := &testBlockChain{statedb, 1000000, new(event.Feed)}
 
 	config := testTxPoolConfig
@@ -858,8 +851,7 @@ func testTransactionQueueTimeLimiting(t *testing.T, nolocals bool) {
 	evictionInterval = time.Second
 
 	// Create the pool to test the non-expiration enforcement
-	db := ethdb.NewMemDatabase()
-	statedb, _ := state.New(common.Hash{}, state.NewDatabase(db))
+	statedb, _ := state.New(common.Hash{}, state.NewDatabase(ethdb.NewMemDatabase()))
 	blockchain := &testBlockChain{statedb, 1000000, new(event.Feed)}
 
 	config := testTxPoolConfig
@@ -1013,8 +1005,7 @@ func TestTransactionPendingGlobalLimiting(t *testing.T) {
 	t.Parallel()
 
 	// Create the pool to test the limit enforcement with
-	db := ethdb.NewMemDatabase()
-	statedb, _ := state.New(common.Hash{}, state.NewDatabase(db))
+	statedb, _ := state.New(common.Hash{}, state.NewDatabase(ethdb.NewMemDatabase()))
 	blockchain := &testBlockChain{statedb, 1000000, new(event.Feed)}
 
 	config := testTxPoolConfig
@@ -1060,8 +1051,7 @@ func TestTransactionCapClearsFromAll(t *testing.T) {
 	t.Parallel()
 
 	// Create the pool to test the limit enforcement with
-	db := ethdb.NewMemDatabase()
-	statedb, _ := state.New(common.Hash{}, state.NewDatabase(db))
+	statedb, _ := state.New(common.Hash{}, state.NewDatabase(ethdb.NewMemDatabase()))
 	blockchain := &testBlockChain{statedb, 1000000, new(event.Feed)}
 
 	config := testTxPoolConfig
@@ -1095,8 +1085,7 @@ func TestTransactionPendingMinimumAllowance(t *testing.T) {
 	t.Parallel()
 
 	// Create the pool to test the limit enforcement with
-	db := ethdb.NewMemDatabase()
-	statedb, _ := state.New(common.Hash{}, state.NewDatabase(db))
+	statedb, _ := state.New(common.Hash{}, state.NewDatabase(ethdb.NewMemDatabase()))
 	blockchain := &testBlockChain{statedb, 1000000, new(event.Feed)}
 
 	config := testTxPoolConfig
@@ -1144,8 +1133,7 @@ func TestTransactionPoolRepricing(t *testing.T) {
 	t.Parallel()
 
 	// Create the pool to test the pricing enforcement with
-	db := ethdb.NewMemDatabase()
-	statedb, _ := state.New(common.Hash{}, state.NewDatabase(db))
+	statedb, _ := state.New(common.Hash{}, state.NewDatabase(ethdb.NewMemDatabase()))
 	blockchain := &testBlockChain{statedb, 1000000, new(event.Feed)}
 
 	pool := NewTxPool(testTxPoolConfig, params.TestChainConfig, blockchain)
@@ -1266,8 +1254,7 @@ func TestTransactionPoolRepricingKeepsLocals(t *testing.T) {
 	t.Parallel()
 
 	// Create the pool to test the pricing enforcement with
-	db := ethdb.NewMemDatabase()
-	statedb, _ := state.New(common.Hash{}, state.NewDatabase(db))
+	statedb, _ := state.New(common.Hash{}, state.NewDatabase(ethdb.NewMemDatabase()))
 	blockchain := &testBlockChain{statedb, 1000000, new(event.Feed)}
 
 	pool := NewTxPool(testTxPoolConfig, params.TestChainConfig, blockchain)
@@ -1329,8 +1316,7 @@ func TestTransactionPoolUnderpricing(t *testing.T) {
 	t.Parallel()
 
 	// Create the pool to test the pricing enforcement with
-	db := ethdb.NewMemDatabase()
-	statedb, _ := state.New(common.Hash{}, state.NewDatabase(db))
+	statedb, _ := state.New(common.Hash{}, state.NewDatabase(ethdb.NewMemDatabase()))
 	blockchain := &testBlockChain{statedb, 1000000, new(event.Feed)}
 
 	config := testTxPoolConfig
@@ -1436,8 +1422,7 @@ func TestTransactionPoolStableUnderpricing(t *testing.T) {
 	t.Parallel()
 
 	// Create the pool to test the pricing enforcement with
-	db := ethdb.NewMemDatabase()
-	statedb, _ := state.New(common.Hash{}, state.NewDatabase(db))
+	statedb, _ := state.New(common.Hash{}, state.NewDatabase(ethdb.NewMemDatabase()))
 	blockchain := &testBlockChain{statedb, 1000000, new(event.Feed)}
 
 	config := testTxPoolConfig
@@ -1503,8 +1488,7 @@ func TestTransactionReplacement(t *testing.T) {
 	t.Parallel()
 
 	// Create the pool to test the pricing enforcement with
-	db := ethdb.NewMemDatabase()
-	statedb, _ := state.New(common.Hash{}, state.NewDatabase(db))
+	statedb, _ := state.New(common.Hash{}, state.NewDatabase(ethdb.NewMemDatabase()))
 	blockchain := &testBlockChain{statedb, 1000000, new(event.Feed)}
 
 	pool := NewTxPool(testTxPoolConfig, params.TestChainConfig, blockchain)
@@ -1598,8 +1582,7 @@ func testTransactionJournaling(t *testing.T, nolocals bool) {
 	os.Remove(journal)
 
 	// Create the original pool to inject transaction into the journal
-	db := ethdb.NewMemDatabase()
-	statedb, _ := state.New(common.Hash{}, state.NewDatabase(db))
+	statedb, _ := state.New(common.Hash{}, state.NewDatabase(ethdb.NewMemDatabase()))
 	blockchain := &testBlockChain{statedb, 1000000, new(event.Feed)}
 
 	config := testTxPoolConfig
@@ -1697,8 +1680,7 @@ func TestTransactionStatusCheck(t *testing.T) {
 	t.Parallel()
 
 	// Create the pool to test the status retrievals with
-	db := ethdb.NewMemDatabase()
-	statedb, _ := state.New(common.Hash{}, state.NewDatabase(db))
+	statedb, _ := state.New(common.Hash{}, state.NewDatabase(ethdb.NewMemDatabase()))
 	blockchain := &testBlockChain{statedb, 1000000, new(event.Feed)}
 
 	pool := NewTxPool(testTxPoolConfig, params.TestChainConfig, blockchain)
diff --git a/core/vm/runtime/runtime.go b/core/vm/runtime/runtime.go
index 8de73e5ab3ef..c8c5d34d9d41 100644
--- a/core/vm/runtime/runtime.go
+++ b/core/vm/runtime/runtime.go
@@ -99,8 +99,7 @@ func Execute(code, input []byte, cfg *Config) ([]byte, *state.StateDB, error) {
 	setDefaults(cfg)
 
 	if cfg.State == nil {
-		db := ethdb.NewMemDatabase()
-		cfg.State, _ = state.New(common.Hash{}, state.NewDatabase(db))
+		cfg.State, _ = state.New(common.Hash{}, state.NewDatabase(ethdb.NewMemDatabase()))
 	}
 	var (
 		address = common.BytesToAddress([]byte("contract"))
@@ -130,8 +129,7 @@ func Create(input []byte, cfg *Config) ([]byte, common.Address, uint64, error) {
 	setDefaults(cfg)
 
 	if cfg.State == nil {
-		db := ethdb.NewMemDatabase()
-		cfg.State, _ = state.New(common.Hash{}, state.NewDatabase(db))
+		cfg.State, _ = state.New(common.Hash{}, state.NewDatabase(ethdb.NewMemDatabase()))
 	}
 	var (
 		vmenv  = NewEnv(cfg)
diff --git a/core/vm/runtime/runtime_test.go b/core/vm/runtime/runtime_test.go
index c061dc2ec541..ef664bda30cd 100644
--- a/core/vm/runtime/runtime_test.go
+++ b/core/vm/runtime/runtime_test.go
@@ -94,8 +94,7 @@ func TestExecute(t *testing.T) {
 }
 
 func TestCall(t *testing.T) {
-	db := ethdb.NewMemDatabase()
-	state, _ := state.New(common.Hash{}, state.NewDatabase(db))
+	state, _ := state.New(common.Hash{}, state.NewDatabase(ethdb.NewMemDatabase()))
 	address := common.HexToAddress("0x0a")
 	state.SetCode(address, []byte{
 		byte(vm.PUSH1), 10,
diff --git a/eth/api_test.go b/eth/api_test.go
index ed1889cd26bf..47b062a40c46 100644
--- a/eth/api_test.go
+++ b/eth/api_test.go
@@ -31,8 +31,7 @@ var dumper = spew.ConfigState{Indent: "    "}
 func TestStorageRangeAt(t *testing.T) {
 	// Create a state where account 0x010000... has a few storage entries.
 	var (
-		db       = ethdb.NewMemDatabase()
-		state, _ = state.New(common.Hash{}, state.NewDatabase(db))
+		state, _ = state.New(common.Hash{}, state.NewDatabase(ethdb.NewMemDatabase()))
 		addr     = common.Address{0x01}
 		keys     = []common.Hash{ // hashes of Keys of storage
 			common.HexToHash("340dd630ad21bf010b4e676dbfa9ba9a02175262d1fa356232cfde6cb5b47ef2"),
diff --git a/eth/tracers/tracers_test.go b/eth/tracers/tracers_test.go
index a58ef1af3380..d25fc459a1d0 100644
--- a/eth/tracers/tracers_test.go
+++ b/eth/tracers/tracers_test.go
@@ -159,8 +159,7 @@ func TestCallTracer(t *testing.T) {
 				GasLimit:    uint64(test.Context.GasLimit),
 				GasPrice:    tx.GasPrice(),
 			}
-			db := ethdb.NewMemDatabase()
-			statedb := tests.MakePreState(db, test.Genesis.Alloc)
+			statedb := tests.MakePreState(ethdb.NewMemDatabase(), test.Genesis.Alloc)
 
 			// Create the tracer, the EVM environment and run it
 			tracer, err := New("callTracer")
diff --git a/ethdb/database_test.go b/ethdb/database_test.go
index bc680ff93887..2deb50988caa 100644
--- a/ethdb/database_test.go
+++ b/ethdb/database_test.go
@@ -53,8 +53,7 @@ func TestLDB_PutGet(t *testing.T) {
 }
 
 func TestMemoryDB_PutGet(t *testing.T) {
-	db := ethdb.NewMemDatabase()
-	testPutGet(db, t)
+	testPutGet(ethdb.NewMemDatabase(), t)
 }
 
 func testPutGet(db ethdb.Database, t *testing.T) {
@@ -131,8 +130,7 @@ func TestLDB_ParallelPutGet(t *testing.T) {
 }
 
 func TestMemoryDB_ParallelPutGet(t *testing.T) {
-	db := ethdb.NewMemDatabase()
-	testParallelPutGet(db, t)
+	testParallelPutGet(ethdb.NewMemDatabase(), t)
 }
 
 func testParallelPutGet(db ethdb.Database, t *testing.T) {
diff --git a/les/handler_test.go b/les/handler_test.go
index d24b2c66599a..31aad3ed450d 100644
--- a/les/handler_test.go
+++ b/les/handler_test.go
@@ -51,8 +51,7 @@ func TestGetBlockHeadersLes1(t *testing.T) { testGetBlockHeaders(t, 1) }
 func TestGetBlockHeadersLes2(t *testing.T) { testGetBlockHeaders(t, 2) }
 
 func testGetBlockHeaders(t *testing.T, protocol int) {
-	db := ethdb.NewMemDatabase()
-	pm := newTestProtocolManagerMust(t, false, downloader.MaxHashFetch+15, nil, nil, nil, db)
+	pm := newTestProtocolManagerMust(t, false, downloader.MaxHashFetch+15, nil, nil, nil, ethdb.NewMemDatabase())
 	bc := pm.blockchain.(*core.BlockChain)
 	peer, _ := newTestPeer(t, "peer", protocol, pm, true)
 	defer peer.close()
@@ -181,8 +180,7 @@ func TestGetBlockBodiesLes1(t *testing.T) { testGetBlockBodies(t, 1) }
 func TestGetBlockBodiesLes2(t *testing.T) { testGetBlockBodies(t, 2) }
 
 func testGetBlockBodies(t *testing.T, protocol int) {
-	db := ethdb.NewMemDatabase()
-	pm := newTestProtocolManagerMust(t, false, downloader.MaxBlockFetch+15, nil, nil, nil, db)
+	pm := newTestProtocolManagerMust(t, false, downloader.MaxBlockFetch+15, nil, nil, nil, ethdb.NewMemDatabase())
 	bc := pm.blockchain.(*core.BlockChain)
 	peer, _ := newTestPeer(t, "peer", protocol, pm, true)
 	defer peer.close()
@@ -259,8 +257,7 @@ func TestGetCodeLes2(t *testing.T) { testGetCode(t, 2) }
 
 func testGetCode(t *testing.T, protocol int) {
 	// Assemble the test environment
-	db := ethdb.NewMemDatabase()
-	pm := newTestProtocolManagerMust(t, false, 4, testChainGen, nil, nil, db)
+	pm := newTestProtocolManagerMust(t, false, 4, testChainGen, nil, nil, ethdb.NewMemDatabase())
 	bc := pm.blockchain.(*core.BlockChain)
 	peer, _ := newTestPeer(t, "peer", protocol, pm, true)
 	defer peer.close()
diff --git a/tests/state_test_util.go b/tests/state_test_util.go
index ff71e0eb917a..84581fae18d9 100644
--- a/tests/state_test_util.go
+++ b/tests/state_test_util.go
@@ -126,8 +126,7 @@ func (t *StateTest) Run(subtest StateSubtest, vmconfig vm.Config) (*state.StateD
 		return nil, UnsupportedForkError{subtest.Fork}
 	}
 	block := t.genesis(config).ToBlock(nil)
-	db := ethdb.NewMemDatabase()
-	statedb := MakePreState(db, t.json.Pre)
+	statedb := MakePreState(ethdb.NewMemDatabase(), t.json.Pre)
 
 	post := t.json.Post[subtest.Fork][subtest.Index]
 	msg, err := t.json.Tx.toMessage(post)
diff --git a/tests/vm_test_util.go b/tests/vm_test_util.go
index c9cc4a59ef11..cb81c5b94e39 100644
--- a/tests/vm_test_util.go
+++ b/tests/vm_test_util.go
@@ -79,8 +79,7 @@ type vmExecMarshaling struct {
 }
 
 func (t *VMTest) Run(vmconfig vm.Config) error {
-	db := ethdb.NewMemDatabase()
-	statedb := MakePreState(db, t.json.Pre)
+	statedb := MakePreState(ethdb.NewMemDatabase(), t.json.Pre)
 	ret, gasRemaining, err := t.exec(statedb, vmconfig)
 
 	if t.json.GasRemaining == nil {
diff --git a/trie/secure_trie_test.go b/trie/secure_trie_test.go
index 85173d116fc7..d16d999684a3 100644
--- a/trie/secure_trie_test.go
+++ b/trie/secure_trie_test.go
@@ -28,18 +28,14 @@ import (
 )
 
 func newEmptySecure() *SecureTrie {
-	diskdb := ethdb.NewMemDatabase()
-	triedb := NewDatabase(diskdb)
-
-	trie, _ := NewSecure(common.Hash{}, triedb, 0)
+	trie, _ := NewSecure(common.Hash{}, NewDatabase(ethdb.NewMemDatabase()), 0)
 	return trie
 }
 
 // makeTestSecureTrie creates a large enough secure trie for testing.
 func makeTestSecureTrie() (*Database, *SecureTrie, map[string][]byte) {
 	// Create an empty trie
-	diskdb := ethdb.NewMemDatabase()
-	triedb := NewDatabase(diskdb)
+	triedb := NewDatabase(ethdb.NewMemDatabase())
 
 	trie, _ := NewSecure(common.Hash{}, triedb, 0)
 
diff --git a/trie/sync_test.go b/trie/sync_test.go
index 505d79f25bc7..142a6f5b1a5c 100644
--- a/trie/sync_test.go
+++ b/trie/sync_test.go
@@ -27,8 +27,7 @@ import (
 // makeTestTrie create a sample test trie to test node-wise reconstruction.
 func makeTestTrie() (*Database, *Trie, map[string][]byte) {
 	// Create an empty trie
-	diskdb := ethdb.NewMemDatabase()
-	triedb := NewDatabase(diskdb)
+	triedb := NewDatabase(ethdb.NewMemDatabase())
 	trie, _ := New(common.Hash{}, triedb)
 
 	// Fill it with some arbitrary data
@@ -89,18 +88,13 @@ func checkTrieConsistency(db *Database, root common.Hash) error {
 
 // Tests that an empty trie is not scheduled for syncing.
 func TestEmptyTrieSync(t *testing.T) {
-	diskdbA := ethdb.NewMemDatabase()
-	triedbA := NewDatabase(diskdbA)
-
-	diskdbB := ethdb.NewMemDatabase()
-	triedbB := NewDatabase(diskdbB)
-
-	emptyA, _ := New(common.Hash{}, triedbA)
-	emptyB, _ := New(emptyRoot, triedbB)
+	dbA := NewDatabase(ethdb.NewMemDatabase())
+	dbB := NewDatabase(ethdb.NewMemDatabase())
+	emptyA, _ := New(common.Hash{}, dbA)
+	emptyB, _ := New(emptyRoot, dbB)
 
 	for i, trie := range []*Trie{emptyA, emptyB} {
-		diskdb := ethdb.NewMemDatabase()
-		if req := NewTrieSync(trie.Hash(), diskdb, nil).Missing(1); len(req) != 0 {
+		if req := NewTrieSync(trie.Hash(), ethdb.NewMemDatabase(), nil).Missing(1); len(req) != 0 {
 			t.Errorf("test %d: content requested for empty trie: %v", i, req)
 		}
 	}
diff --git a/trie/trie_test.go b/trie/trie_test.go
index 1a4e3385b9fd..f8e5fd12a184 100644
--- a/trie/trie_test.go
+++ b/trie/trie_test.go
@@ -43,8 +43,7 @@ func init() {
 
 // Used for testing
 func newEmpty() *Trie {
-	diskdb := ethdb.NewMemDatabase()
-	trie, _ := New(common.Hash{}, NewDatabase(diskdb))
+	trie, _ := New(common.Hash{}, NewDatabase(ethdb.NewMemDatabase()))
 	return trie
 }
 
@@ -68,8 +67,7 @@ func TestNull(t *testing.T) {
 }
 
 func TestMissingRoot(t *testing.T) {
-	diskdb := ethdb.NewMemDatabase()
-	trie, err := New(common.HexToHash("0beec7b5ea3f0fdbc95d0dd47f3c5bc275da8a33"), NewDatabase(diskdb))
+	trie, err := New(common.HexToHash("0beec7b5ea3f0fdbc95d0dd47f3c5bc275da8a33"), NewDatabase(ethdb.NewMemDatabase()))
 	if trie != nil {
 		t.Error("New returned non-nil trie for invalid root")
 	}
@@ -413,8 +411,7 @@ func (randTest) Generate(r *rand.Rand, size int) reflect.Value {
 }
 
 func runRandTest(rt randTest) bool {
-	diskdb := ethdb.NewMemDatabase()
-	triedb := NewDatabase(diskdb)
+	triedb := NewDatabase(ethdb.NewMemDatabase())
 
 	tr, _ := New(common.Hash{}, triedb)
 	values := make(map[string]string) // tracks content of the trie