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

4 files changed, 10 insertions, 10 deletions

diff --git a/light/lightchain_test.go b/light/lightchain_test.go
index b8ab1c51c..c0aa51da2 100644
--- a/light/lightchain_test.go
+++ b/light/lightchain_test.go
@@ -52,7 +52,7 @@ func makeHeaderChain(parent *types.Header, n int, db ethdb.Database, seed int) [
 // chain. Depending on the full flag, if creates either a full block chain or a
 // header only chain.
 func newCanonical(n int) (ethdb.Database, *LightChain, error) {
-	db, _ := ethdb.NewMemDatabase()
+	db := ethdb.NewMemDatabase()
 	gspec := core.Genesis{Config: params.TestChainConfig}
 	genesis := gspec.MustCommit(db)
 	blockchain, _ := NewLightChain(&dummyOdr{db: db}, gspec.Config, ethash.NewFaker())
@@ -69,7 +69,7 @@ func newCanonical(n int) (ethdb.Database, *LightChain, error) {
 
 // newTestLightChain creates a LightChain that doesn't validate anything.
 func newTestLightChain() *LightChain {
-	db, _ := ethdb.NewMemDatabase()
+	db := ethdb.NewMemDatabase()
 	gspec := &core.Genesis{
 		Difficulty: big.NewInt(1),
 		Config:     params.TestChainConfig,
diff --git a/light/odr_test.go b/light/odr_test.go
index cc7475df3..3e7ac1011 100644
--- a/light/odr_test.go
+++ b/light/odr_test.go
@@ -245,8 +245,8 @@ func testChainGen(i int, block *core.BlockGen) {
 
 func testChainOdr(t *testing.T, protocol int, fn odrTestFn) {
 	var (
-		sdb, _  = ethdb.NewMemDatabase()
-		ldb, _  = ethdb.NewMemDatabase()
+		sdb     = ethdb.NewMemDatabase()
+		ldb     = ethdb.NewMemDatabase()
 		gspec   = core.Genesis{Alloc: core.GenesisAlloc{testBankAddress: {Balance: testBankFunds}}}
 		genesis = gspec.MustCommit(sdb)
 	)
diff --git a/light/trie_test.go b/light/trie_test.go
index 0d6b2cc1d..84c6f162f 100644
--- a/light/trie_test.go
+++ b/light/trie_test.go
@@ -34,10 +34,10 @@ import (
 
 func TestNodeIterator(t *testing.T) {
 	var (
-		fulldb, _  = ethdb.NewMemDatabase()
-		lightdb, _ = ethdb.NewMemDatabase()
-		gspec      = core.Genesis{Alloc: core.GenesisAlloc{testBankAddress: {Balance: testBankFunds}}}
-		genesis    = gspec.MustCommit(fulldb)
+		fulldb  = ethdb.NewMemDatabase()
+		lightdb = ethdb.NewMemDatabase()
+		gspec   = core.Genesis{Alloc: core.GenesisAlloc{testBankAddress: {Balance: testBankFunds}}}
+		genesis = gspec.MustCommit(fulldb)
 	)
 	gspec.MustCommit(lightdb)
 	blockchain, _ := core.NewBlockChain(fulldb, nil, params.TestChainConfig, ethash.NewFullFaker(), vm.Config{})
diff --git a/light/txpool_test.go b/light/txpool_test.go
index 13d7d3ceb..ccbd83a94 100644
--- a/light/txpool_test.go
+++ b/light/txpool_test.go
@@ -81,8 +81,8 @@ func TestTxPool(t *testing.T) {
 	}
 
 	var (
-		sdb, _  = ethdb.NewMemDatabase()
-		ldb, _  = ethdb.NewMemDatabase()
+		sdb     = ethdb.NewMemDatabase()
+		ldb     = ethdb.NewMemDatabase()
 		gspec   = core.Genesis{Alloc: core.GenesisAlloc{testBankAddress: {Balance: testBankFunds}}}
 		genesis = gspec.MustCommit(sdb)
 	)