all: get rid of error when creating memory database (#16716)

* all: get rid of error when create mdb

* core: clean up variables definition

* all: inline mdb definition

7 files changed, 14 insertions, 16 deletions

diff --git a/eth/api_test.go b/eth/api_test.go
index 900a82bb6..47b062a40 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/downloader/downloader_test.go b/eth/downloader/downloader_test.go
index e85e234c0..d1a9a8694 100644
--- a/eth/downloader/downloader_test.go
+++ b/eth/downloader/downloader_test.go
@@ -75,7 +75,7 @@ type downloadTester struct {
 
 // newTester creates a new downloader test mocker.
 func newTester() *downloadTester {
-	testdb, _ := ethdb.NewMemDatabase()
+	testdb := ethdb.NewMemDatabase()
 	genesis := core.GenesisBlockForTesting(testdb, testAddress, big.NewInt(1000000000))
 
 	tester := &downloadTester{
@@ -93,7 +93,7 @@ func newTester() *downloadTester {
 		peerChainTds:      make(map[string]map[common.Hash]*big.Int),
 		peerMissingStates: make(map[string]map[common.Hash]bool),
 	}
-	tester.stateDb, _ = ethdb.NewMemDatabase()
+	tester.stateDb = ethdb.NewMemDatabase()
 	tester.stateDb.Put(genesis.Root().Bytes(), []byte{0x00})
 
 	tester.downloader = New(FullSync, tester.stateDb, new(event.TypeMux), tester, nil, tester.dropPeer)
diff --git a/eth/fetcher/fetcher_test.go b/eth/fetcher/fetcher_test.go
index 1e536fcac..3d4f0d1e5 100644
--- a/eth/fetcher/fetcher_test.go
+++ b/eth/fetcher/fetcher_test.go
@@ -34,7 +34,7 @@ import (
 )
 
 var (
-	testdb, _    = ethdb.NewMemDatabase()
+	testdb       = ethdb.NewMemDatabase()
 	testKey, _   = crypto.HexToECDSA("b71c71a67e1177ad4e901695e1b4b9ee17ae16c6668d313eac2f96dbcda3f291")
 	testAddress  = crypto.PubkeyToAddress(testKey.PublicKey)
 	genesis      = core.GenesisBlockForTesting(testdb, testAddress, big.NewInt(1000000000))
diff --git a/eth/filters/filter_system_test.go b/eth/filters/filter_system_test.go
index 73819eadc..b4df24b47 100644
--- a/eth/filters/filter_system_test.go
+++ b/eth/filters/filter_system_test.go
@@ -153,7 +153,7 @@ func TestBlockSubscription(t *testing.T) {
 
 	var (
 		mux         = new(event.TypeMux)
-		db, _       = ethdb.NewMemDatabase()
+		db          = ethdb.NewMemDatabase()
 		txFeed      = new(event.Feed)
 		rmLogsFeed  = new(event.Feed)
 		logsFeed    = new(event.Feed)
@@ -210,7 +210,7 @@ func TestPendingTxFilter(t *testing.T) {
 
 	var (
 		mux        = new(event.TypeMux)
-		db, _      = ethdb.NewMemDatabase()
+		db         = ethdb.NewMemDatabase()
 		txFeed     = new(event.Feed)
 		rmLogsFeed = new(event.Feed)
 		logsFeed   = new(event.Feed)
@@ -273,7 +273,7 @@ func TestPendingTxFilter(t *testing.T) {
 func TestLogFilterCreation(t *testing.T) {
 	var (
 		mux        = new(event.TypeMux)
-		db, _      = ethdb.NewMemDatabase()
+		db         = ethdb.NewMemDatabase()
 		txFeed     = new(event.Feed)
 		rmLogsFeed = new(event.Feed)
 		logsFeed   = new(event.Feed)
@@ -322,7 +322,7 @@ func TestInvalidLogFilterCreation(t *testing.T) {
 
 	var (
 		mux        = new(event.TypeMux)
-		db, _      = ethdb.NewMemDatabase()
+		db         = ethdb.NewMemDatabase()
 		txFeed     = new(event.Feed)
 		rmLogsFeed = new(event.Feed)
 		logsFeed   = new(event.Feed)
@@ -352,7 +352,7 @@ func TestLogFilter(t *testing.T) {
 
 	var (
 		mux        = new(event.TypeMux)
-		db, _      = ethdb.NewMemDatabase()
+		db         = ethdb.NewMemDatabase()
 		txFeed     = new(event.Feed)
 		rmLogsFeed = new(event.Feed)
 		logsFeed   = new(event.Feed)
@@ -471,7 +471,7 @@ func TestPendingLogsSubscription(t *testing.T) {
 
 	var (
 		mux        = new(event.TypeMux)
-		db, _      = ethdb.NewMemDatabase()
+		db         = ethdb.NewMemDatabase()
 		txFeed     = new(event.Feed)
 		rmLogsFeed = new(event.Feed)
 		logsFeed   = new(event.Feed)
diff --git a/eth/handler_test.go b/eth/handler_test.go
index e336dfa28..fee4114eb 100644
--- a/eth/handler_test.go
+++ b/eth/handler_test.go
@@ -366,7 +366,7 @@ func testGetNodeData(t *testing.T, protocol int) {
 			t.Errorf("data hash mismatch: have %x, want %x", hash, want)
 		}
 	}
-	statedb, _ := ethdb.NewMemDatabase()
+	statedb := ethdb.NewMemDatabase()
 	for i := 0; i < len(data); i++ {
 		statedb.Put(hashes[i].Bytes(), data[i])
 	}
@@ -468,7 +468,7 @@ func testDAOChallenge(t *testing.T, localForked, remoteForked bool, timeout bool
 	var (
 		evmux         = new(event.TypeMux)
 		pow           = ethash.NewFaker()
-		db, _         = ethdb.NewMemDatabase()
+		db            = ethdb.NewMemDatabase()
 		config        = &params.ChainConfig{DAOForkBlock: big.NewInt(1), DAOForkSupport: localForked}
 		gspec         = &core.Genesis{Config: config}
 		genesis       = gspec.MustCommit(db)
diff --git a/eth/helper_test.go b/eth/helper_test.go
index 2b05cea80..8a0260fc9 100644
--- a/eth/helper_test.go
+++ b/eth/helper_test.go
@@ -53,7 +53,7 @@ func newTestProtocolManager(mode downloader.SyncMode, blocks int, generator func
 	var (
 		evmux  = new(event.TypeMux)
 		engine = ethash.NewFaker()
-		db, _  = ethdb.NewMemDatabase()
+		db     = ethdb.NewMemDatabase()
 		gspec  = &core.Genesis{
 			Config: params.TestChainConfig,
 			Alloc:  core.GenesisAlloc{testBank: {Balance: big.NewInt(1000000)}},
diff --git a/eth/tracers/tracers_test.go b/eth/tracers/tracers_test.go
index bf8120228..d25fc459a 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")