diff --git a/signer/core/api.go b/signer/core/api.go
index 244767acaf..c10bf578d2 100644
--- a/signer/core/api.go
+++ b/signer/core/api.go
@@ -269,7 +269,7 @@ type (
 	}
 )
 
-var ErrRequestDenied = errors.New("Request denied")
+var ErrRequestDenied = errors.New("request denied")
 
 // NewSignerAPI creates a new API that can be used for Account management.
 // ksLocation specifies the directory where to store the password protected private
@@ -552,6 +552,9 @@ func (api *SignerAPI) SignTransaction(ctx context.Context, args SendTxArgs, meth
 	}
 
 	rlpdata, err := rlp.EncodeToBytes(signedTx)
+	if err != nil {
+		return nil, err
+	}
 	response := ethapi.SignTransactionResult{Raw: rlpdata, Tx: signedTx}
 
 	// Finally, send the signed tx to the UI
diff --git a/signer/core/api_test.go b/signer/core/api_test.go
index 30948f99bf..800020b0cf 100644
--- a/signer/core/api_test.go
+++ b/signer/core/api_test.go
@@ -71,7 +71,7 @@ func (ui *headlessUi) ApproveTx(request *core.SignTxRequest) (core.SignTxRespons
 }
 
 func (ui *headlessUi) ApproveSignData(request *core.SignDataRequest) (core.SignDataResponse, error) {
-	approved := "Y" == <-ui.approveCh
+	approved := (<-ui.approveCh == "Y")
 	return core.SignDataResponse{approved}, nil
 }
 
@@ -91,7 +91,7 @@ func (ui *headlessUi) ApproveListing(request *core.ListRequest) (core.ListRespon
 }
 
 func (ui *headlessUi) ApproveNewAccount(request *core.NewAccountRequest) (core.NewAccountResponse, error) {
-	if "Y" == <-ui.approveCh {
+	if <-ui.approveCh == "Y" {
 		return core.NewAccountResponse{true}, nil
 	}
 	return core.NewAccountResponse{false}, nil
diff --git a/signer/core/cliui.go b/signer/core/cliui.go
index 1502238bf7..1e033299af 100644
--- a/signer/core/cliui.go
+++ b/signer/core/cliui.go
@@ -58,34 +58,6 @@ func (ui *CommandlineUI) readString() string {
 	}
 }
 
-// readPassword reads a single line from stdin, trimming it from the trailing new
-// line and returns it. The input will not be echoed.
-func (ui *CommandlineUI) readPassword() string {
-	fmt.Printf("Enter password to approve:\n")
-	fmt.Printf("> ")
-
-	text, err := terminal.ReadPassword(int(os.Stdin.Fd()))
-	if err != nil {
-		log.Crit("Failed to read password", "err", err)
-	}
-	fmt.Println()
-	fmt.Println("-----------------------")
-	return string(text)
-}
-
-// readPassword reads a single line from stdin, trimming it from the trailing new
-// line and returns it. The input will not be echoed.
-func (ui *CommandlineUI) readPasswordText(inputstring string) string {
-	fmt.Printf("Enter %s:\n", inputstring)
-	fmt.Printf("> ")
-	text, err := terminal.ReadPassword(int(os.Stdin.Fd()))
-	if err != nil {
-		log.Crit("Failed to read password", "err", err)
-	}
-	fmt.Println("-----------------------")
-	return string(text)
-}
-
 func (ui *CommandlineUI) OnInputRequired(info UserInputRequest) (UserInputResponse, error) {
 
 	fmt.Printf("## %s\n\n%s\n", info.Title, info.Prompt)
diff --git a/signer/core/stdioui.go b/signer/core/stdioui.go
index 9ffe1398d4..6963a89122 100644
--- a/signer/core/stdioui.go
+++ b/signer/core/stdioui.go
@@ -18,7 +18,6 @@ package core
 
 import (
 	"context"
-	"sync"
 
 	"github.com/ethereum/go-ethereum/internal/ethapi"
 	"github.com/ethereum/go-ethereum/log"
@@ -27,7 +26,6 @@ import (
 
 type StdIOUI struct {
 	client rpc.Client
-	mu     sync.Mutex
 }
 
 func NewStdIOUI() *StdIOUI {
diff --git a/signer/core/types.go b/signer/core/types.go
index f147f06cd1..58b377c8d8 100644
--- a/signer/core/types.go
+++ b/signer/core/types.go
@@ -60,7 +60,7 @@ func (v *ValidationMessages) getWarnings() error {
 		}
 	}
 	if len(messages) > 0 {
-		return fmt.Errorf("Validation failed: %s", strings.Join(messages, ","))
+		return fmt.Errorf("validation failed: %s", strings.Join(messages, ","))
 	}
 	return nil
 }
diff --git a/signer/core/uiapi.go b/signer/core/uiapi.go
index 7c2d233f89..36735d37ee 100644
--- a/signer/core/uiapi.go
+++ b/signer/core/uiapi.go
@@ -173,7 +173,7 @@ func (s *UIServerAPI) Export(ctx context.Context, addr common.Address) (json.Raw
 		return nil, err
 	}
 	if wallet.URL().Scheme != keystore.KeyStoreScheme {
-		return nil, fmt.Errorf("Account is not a keystore-account")
+		return nil, fmt.Errorf("account is not a keystore-account")
 	}
 	return ioutil.ReadFile(wallet.URL().Path)
 }
diff --git a/signer/rules/deps/bindata.go b/signer/rules/deps/bindata.go
index 0b27f45172..401dfca5a9 100644
--- a/signer/rules/deps/bindata.go
+++ b/signer/rules/deps/bindata.go
@@ -1,8 +1,6 @@
-// Code generated by go-bindata.
+// Package deps Code generated by go-bindata. (@generated) DO NOT EDIT.
 // sources:
 // bignumber.js
-// DO NOT EDIT!
-
 package deps
 
 import (
@@ -20,7 +18,7 @@ import (
 func bindataRead(data []byte, name string) ([]byte, error) {
 	gz, err := gzip.NewReader(bytes.NewBuffer(data))
 	if err != nil {
-		return nil, fmt.Errorf("Read %q: %v", name, err)
+		return nil, fmt.Errorf("read %q: %v", name, err)
 	}
 
 	var buf bytes.Buffer
@@ -28,7 +26,7 @@ func bindataRead(data []byte, name string) ([]byte, error) {
 	clErr := gz.Close()
 
 	if err != nil {
-		return nil, fmt.Errorf("Read %q: %v", name, err)
+		return nil, fmt.Errorf("read %q: %v", name, err)
 	}
 	if clErr != nil {
 		return nil, err
@@ -49,21 +47,32 @@ type bindataFileInfo struct {
 	modTime time.Time
 }
 
+// Name return file name
 func (fi bindataFileInfo) Name() string {
 	return fi.name
 }
+
+// Size return file size
 func (fi bindataFileInfo) Size() int64 {
 	return fi.size
 }
+
+// Mode return file mode
 func (fi bindataFileInfo) Mode() os.FileMode {
 	return fi.mode
 }
+
+// ModTime return file modify time
 func (fi bindataFileInfo) ModTime() time.Time {
 	return fi.modTime
 }
+
+// IsDir return file whether a directory
 func (fi bindataFileInfo) IsDir() bool {
-	return false
+	return fi.mode&os.ModeDir != 0
 }
+
+// Sys return file is sys mode
 func (fi bindataFileInfo) Sys() interface{} {
 	return nil
 }
diff --git a/signer/rules/rules.go b/signer/rules/rules.go
index 39538d18b9..cb375a62ad 100644
--- a/signer/rules/rules.go
+++ b/signer/rules/rules.go
@@ -152,7 +152,7 @@ func (r *rulesetUI) checkApproval(jsfunc string, jsarg []byte, err error) (bool,
 		log.Info("Op rejected")
 		return false, nil
 	}
-	return false, fmt.Errorf("Unknown response")
+	return false, fmt.Errorf("unknown response")
 }
 
 func (r *rulesetUI) ApproveTx(request *core.SignTxRequest) (core.SignTxResponse, error) {
diff --git a/signer/storage/storage.go b/signer/storage/storage.go
index 06b0fd98f7..33c0d66f9b 100644
--- a/signer/storage/storage.go
+++ b/signer/storage/storage.go
@@ -41,8 +41,7 @@ type Storage interface {
 // EphemeralStorage is an in-memory storage that does
 // not persist values to disk. Mainly used for testing
 type EphemeralStorage struct {
-	data      map[string]string
-	namespace string
+	data map[string]string
 }
 
 // Put stores a value by key. 0-length keys results in noop.
@@ -83,5 +82,5 @@ type NoStorage struct{}
 func (s *NoStorage) Put(key, value string) {}
 func (s *NoStorage) Del(key string)        {}
 func (s *NoStorage) Get(key string) (string, error) {
-	return "", errors.New("I forgot")
+	return "", errors.New("missing key, I probably forgot")
 }
diff --git a/tests/block_test_util.go b/tests/block_test_util.go
index 81dd7b1d04..b5f1de3efc 100644
--- a/tests/block_test_util.go
+++ b/tests/block_test_util.go
@@ -179,7 +179,7 @@ func (t *BlockTest) insertBlocks(blockchain *core.BlockChain) ([]btBlock, error)
 			if b.BlockHeader == nil {
 				continue // OK - block is supposed to be invalid, continue with next block
 			} else {
-				return nil, fmt.Errorf("Block RLP decoding failed when expected to succeed: %v", err)
+				return nil, fmt.Errorf("block RLP decoding failed when expected to succeed: %v", err)
 			}
 		}
 		// RLP decoding worked, try to insert into chain:
@@ -189,16 +189,16 @@ func (t *BlockTest) insertBlocks(blockchain *core.BlockChain) ([]btBlock, error)
 			if b.BlockHeader == nil {
 				continue // OK - block is supposed to be invalid, continue with next block
 			} else {
-				return nil, fmt.Errorf("Block #%v insertion into chain failed: %v", blocks[i].Number(), err)
+				return nil, fmt.Errorf("block #%v insertion into chain failed: %v", blocks[i].Number(), err)
 			}
 		}
 		if b.BlockHeader == nil {
-			return nil, fmt.Errorf("Block insertion should have failed")
+			return nil, fmt.Errorf("block insertion should have failed")
 		}
 
 		// validate RLP decoding by checking all values against test file JSON
 		if err = validateHeader(b.BlockHeader, cb.Header()); err != nil {
-			return nil, fmt.Errorf("Deserialised block header validation failed: %v", err)
+			return nil, fmt.Errorf("deserialised block header validation failed: %v", err)
 		}
 		validBlocks = append(validBlocks, b)
 	}
@@ -207,49 +207,49 @@ func (t *BlockTest) insertBlocks(blockchain *core.BlockChain) ([]btBlock, error)
 
 func validateHeader(h *btHeader, h2 *types.Header) error {
 	if h.Bloom != h2.Bloom {
-		return fmt.Errorf("Bloom: want: %x have: %x", h.Bloom, h2.Bloom)
+		return fmt.Errorf("bloom: want: %x have: %x", h.Bloom, h2.Bloom)
 	}
 	if h.Coinbase != h2.Coinbase {
-		return fmt.Errorf("Coinbase: want: %x have: %x", h.Coinbase, h2.Coinbase)
+		return fmt.Errorf("coinbase: want: %x have: %x", h.Coinbase, h2.Coinbase)
 	}
 	if h.MixHash != h2.MixDigest {
 		return fmt.Errorf("MixHash: want: %x have: %x", h.MixHash, h2.MixDigest)
 	}
 	if h.Nonce != h2.Nonce {
-		return fmt.Errorf("Nonce: want: %x have: %x", h.Nonce, h2.Nonce)
+		return fmt.Errorf("nonce: want: %x have: %x", h.Nonce, h2.Nonce)
 	}
 	if h.Number.Cmp(h2.Number) != 0 {
-		return fmt.Errorf("Number: want: %v have: %v", h.Number, h2.Number)
+		return fmt.Errorf("number: want: %v have: %v", h.Number, h2.Number)
 	}
 	if h.ParentHash != h2.ParentHash {
-		return fmt.Errorf("Parent hash: want: %x have: %x", h.ParentHash, h2.ParentHash)
+		return fmt.Errorf("parent hash: want: %x have: %x", h.ParentHash, h2.ParentHash)
 	}
 	if h.ReceiptTrie != h2.ReceiptHash {
-		return fmt.Errorf("Receipt hash: want: %x have: %x", h.ReceiptTrie, h2.ReceiptHash)
+		return fmt.Errorf("receipt hash: want: %x have: %x", h.ReceiptTrie, h2.ReceiptHash)
 	}
 	if h.TransactionsTrie != h2.TxHash {
-		return fmt.Errorf("Tx hash: want: %x have: %x", h.TransactionsTrie, h2.TxHash)
+		return fmt.Errorf("tx hash: want: %x have: %x", h.TransactionsTrie, h2.TxHash)
 	}
 	if h.StateRoot != h2.Root {
-		return fmt.Errorf("State hash: want: %x have: %x", h.StateRoot, h2.Root)
+		return fmt.Errorf("state hash: want: %x have: %x", h.StateRoot, h2.Root)
 	}
 	if h.UncleHash != h2.UncleHash {
-		return fmt.Errorf("Uncle hash: want: %x have: %x", h.UncleHash, h2.UncleHash)
+		return fmt.Errorf("uncle hash: want: %x have: %x", h.UncleHash, h2.UncleHash)
 	}
 	if !bytes.Equal(h.ExtraData, h2.Extra) {
-		return fmt.Errorf("Extra data: want: %x have: %x", h.ExtraData, h2.Extra)
+		return fmt.Errorf("extra data: want: %x have: %x", h.ExtraData, h2.Extra)
 	}
 	if h.Difficulty.Cmp(h2.Difficulty) != 0 {
-		return fmt.Errorf("Difficulty: want: %v have: %v", h.Difficulty, h2.Difficulty)
+		return fmt.Errorf("difficulty: want: %v have: %v", h.Difficulty, h2.Difficulty)
 	}
 	if h.GasLimit != h2.GasLimit {
-		return fmt.Errorf("GasLimit: want: %d have: %d", h.GasLimit, h2.GasLimit)
+		return fmt.Errorf("gasLimit: want: %d have: %d", h.GasLimit, h2.GasLimit)
 	}
 	if h.GasUsed != h2.GasUsed {
-		return fmt.Errorf("GasUsed: want: %d have: %d", h.GasUsed, h2.GasUsed)
+		return fmt.Errorf("gasUsed: want: %d have: %d", h.GasUsed, h2.GasUsed)
 	}
 	if h.Timestamp != h2.Time {
-		return fmt.Errorf("Timestamp: want: %v have: %v", h.Timestamp, h2.Time)
+		return fmt.Errorf("timestamp: want: %v have: %v", h.Timestamp, h2.Time)
 	}
 	return nil
 }
@@ -287,7 +287,7 @@ func (t *BlockTest) validateImportedHeaders(cm *core.BlockChain, validBlocks []b
 	// be part of the longest chain until last block is imported.
 	for b := cm.CurrentBlock(); b != nil && b.NumberU64() != 0; b = cm.GetBlockByHash(b.Header().ParentHash) {
 		if err := validateHeader(bmap[b.Hash()].BlockHeader, b.Header()); err != nil {
-			return fmt.Errorf("Imported block header validation failed: %v", err)
+			return fmt.Errorf("imported block header validation failed: %v", err)
 		}
 	}
 	return nil
diff --git a/tests/init_test.go b/tests/init_test.go
index 622318adb9..5af3e44bff 100644
--- a/tests/init_test.go
+++ b/tests/init_test.go
@@ -289,3 +289,14 @@ func runTestFunc(runTest interface{}, t *testing.T, name string, m reflect.Value
 		m.MapIndex(reflect.ValueOf(key)),
 	})
 }
+
+func TestMatcherWhitelist(t *testing.T) {
+	t.Parallel()
+	tm := new(testMatcher)
+	tm.whitelist("invalid*")
+	tm.walk(t, rlpTestDir, func(t *testing.T, name string, test *RLPTest) {
+		if name[:len("invalidRLPTest.json")] != "invalidRLPTest.json" {
+			t.Fatalf("invalid test found: %s != invalidRLPTest.json", name)
+		}
+	})
+}
diff --git a/tests/transaction_test_util.go b/tests/transaction_test_util.go
index 7aa1672927..43debae830 100644
--- a/tests/transaction_test_util.go
+++ b/tests/transaction_test_util.go
@@ -86,25 +86,25 @@ func (tt *TransactionTest) Run(config *params.ChainConfig) error {
 
 		if testcase.fork.Sender == (common.UnprefixedAddress{}) {
 			if err == nil {
-				return fmt.Errorf("Expected error, got none (address %v)[%v]", sender.String(), testcase.name)
+				return fmt.Errorf("expected error, got none (address %v)[%v]", sender.String(), testcase.name)
 			}
 			continue
 		}
 		// Should resolve the right address
 		if err != nil {
-			return fmt.Errorf("Got error, expected none: %v", err)
+			return fmt.Errorf("got error, expected none: %v", err)
 		}
 		if sender == nil {
 			return fmt.Errorf("sender was nil, should be %x", common.Address(testcase.fork.Sender))
 		}
 		if *sender != common.Address(testcase.fork.Sender) {
-			return fmt.Errorf("Sender mismatch: got %x, want %x", sender, testcase.fork.Sender)
+			return fmt.Errorf("sender mismatch: got %x, want %x", sender, testcase.fork.Sender)
 		}
 		if txhash == nil {
 			return fmt.Errorf("txhash was nil, should be %x", common.Hash(testcase.fork.Hash))
 		}
 		if *txhash != common.Hash(testcase.fork.Hash) {
-			return fmt.Errorf("Hash mismatch: got %x, want %x", *txhash, testcase.fork.Hash)
+			return fmt.Errorf("hash mismatch: got %x, want %x", *txhash, testcase.fork.Hash)
 		}
 	}
 	return nil