linter: add metalinter to Makefile & apply some fixes

Makefile

@@ -2,7 +2,9 @@
 
 GOTOOLS = \
 	github.com/Masterminds/glide \
-	github.com/jteeuwen/go-bindata/go-bindata
+	github.com/jteeuwen/go-bindata/go-bindata \
+	github.com/alecthomas/gometalinter
+
 REPO:=github.com/tendermint/go-crypto
 
 all: get_vendor_deps test
@@ -31,3 +33,37 @@ codegen:
 	@echo "--> regenerating all interface wrappers"
 	@gen
 	@echo "Done!"
+
+metalinter: ensure_tools
+	@gometalinter --install
+	gometalinter --vendor --deadline=600s --enable-all --disable=lll ./...
+
+metalinter_test: ensure_tools
+	@gometalinter --install
+	gometalinter --vendor --deadline=600s --disable-all  \
+		--enable=aligncheck \
+		--enable=deadcode \
+		--enable=gas \
+		--enable=goconst \
+		--enable=gocyclo \
+		--enable=goimports \
+		--enable=gosimple \
+		--enable=gotype \
+	 	--enable=ineffassign \
+	   	--enable=interfacer \
+		--enable=megacheck \
+	 	--enable=misspell \
+		--enable=safesql \
+		--enable=staticcheck \
+		--enable=structcheck \
+	   	--enable=unconvert \
+		--enable=unused \
+		--enable=vetshadow \
+		--enable=vet \
+		--enable=unparam \
+		--enable=varcheck \
+		./...
+
+		#--enable=dupl \
+		#--enable=errcheck \
+		#--enable=golint \ <== comments on anything exported

_gen.go

@@ -1,6 +0,0 @@
-package main
-
-import (
-	_ "github.com/tendermint/go-wire/gen"
-	_ "github.com/clipperhouse/stringer"
-)

armor.go

@@ -22,7 +22,7 @@ func EncodeArmor(blockType string, headers map[string]string, data []byte) strin
 	if err != nil {
 		PanicSanity("Error encoding ascii armor: " + err.Error())
 	}
-	return string(buf.Bytes())
+	return buf.String()
 }
 
 func DecodeArmor(armorStr string) (blockType string, headers map[string]string, data []byte, err error) {

bcrypt/bcrypt.go

@@ -50,7 +50,7 @@ func (ih InvalidHashPrefixError) Error() string {
 type InvalidCostError int
 
 func (ic InvalidCostError) Error() string {
-	return fmt.Sprintf("crypto/bcrypt: cost %d is outside allowed range (%d,%d)", int(ic), int(MinCost), int(MaxCost))
+	return fmt.Sprintf("crypto/bcrypt: cost %d is outside allowed range (%d,%d)", int(ic), int(MinCost), int(MaxCost)) // nolint: unconvert
 }
 
 const (

hash.go

@@ -1,3 +1,4 @@
+// nolint: goimports
 package crypto
 
 import (

hd/address.go

@@ -11,7 +11,6 @@ import (
 	"errors"
 	"fmt"
 	"hash"
-	"log"
 	"math/big"
 	"strconv"
 	"strings"
@@ -88,18 +87,6 @@ func ComputeTxId(rawTxHex string) string {
 
 // Private methods...
 
-func printKeyInfo(privKeyBytes []byte, pubKeyBytes []byte, chain []byte) {
-	if pubKeyBytes == nil {
-		pubKeyBytes = PubKeyBytesFromPrivKeyBytes(privKeyBytes, true)
-	}
-	addr := AddrFromPubKeyBytes(pubKeyBytes)
-	log.Println("\nprikey:\t%v\npubKeyBytes:\t%v\naddr:\t%v\nchain:\t%v",
-		HexEncode(privKeyBytes),
-		HexEncode(pubKeyBytes),
-		addr,
-		HexEncode(chain))
-}
-
 func DerivePrivateKeyForPath(privKeyBytes []byte, chain []byte, path string) []byte {
 	data := privKeyBytes
 	parts := strings.Split(path, "/")
@@ -144,7 +131,7 @@ func DerivePublicKeyForPath(pubKeyBytes []byte, chain []byte, path string) []byt
 }
 
 func DerivePrivateKey(privKeyBytes []byte, chain []byte, i uint32, prime bool) ([]byte, []byte) {
-	data := []byte{}
+	data := []byte{} // nolint [ megacheck, deadcode ]
 	if prime {
 		i = i | 0x80000000
 		data = append([]byte{byte(0)}, privKeyBytes...)
@@ -177,7 +164,7 @@ func addPoints(a []byte, b []byte) []byte {
 		panic(err)
 	}
 	sumX, sumY := btcec.S256().Add(ap.X, ap.Y, bp.X, bp.Y)
-	sum := (*btcec.PublicKey)(&btcec.PublicKey{
+	sum := (*btcec.PublicKey)(&btcec.PublicKey{ // nolint: unconvert
 		Curve: btcec.S256(),
 		X:     sumX,
 		Y:     sumY,
@@ -248,7 +235,7 @@ func WIFFromPrivKeyBytes(privKeyBytes []byte, compress bool) string {
 
 func PubKeyBytesFromPrivKeyBytes(privKeyBytes []byte, compress bool) (pubKeyBytes []byte) {
 	x, y := btcec.S256().ScalarBaseMult(privKeyBytes)
-	pub := (*btcec.PublicKey)(&btcec.PublicKey{
+	pub := (*btcec.PublicKey)(&btcec.PublicKey{ // nolint: unconvert
 		Curve: btcec.S256(),
 		X:     x,
 		Y:     y,

hd/hd_test.go

@@ -1,10 +1,8 @@
+// nolint: goimports
 package hd
 
 import (
 	"bytes"
-	"crypto/hmac"
-	"crypto/sha512"
-	"encoding/binary"
 	"encoding/hex"
 	"encoding/json"
 	"fmt"
@@ -15,11 +13,6 @@ import (
 	"github.com/stretchr/testify/assert"
 	"github.com/tyler-smith/go-bip39"
 
-	"github.com/btcsuite/btcd/chaincfg"
-	"github.com/btcsuite/btcutil/hdkeychain"
-	"github.com/mndrix/btcutil"
-	"github.com/tyler-smith/go-bip32"
-
 	"github.com/tendermint/go-crypto"
 )
 
@@ -33,7 +26,7 @@ type addrData struct {
 }
 
 // NOTE: atom fundraiser address
-var hdPath string = "m/44'/118'/0'/0/0"
+// var hdPath string = "m/44'/118'/0'/0/0"
 var hdToAddrTable []addrData
 
 func init() {
@@ -109,13 +102,6 @@ func TestReverseBytes(t *testing.T) {
 	}
 }
 
-func ifExit(err error, n int) {
-	if err != nil {
-		fmt.Println(n, err)
-		os.Exit(1)
-	}
-}
-
 func gocrypto(seed []byte) ([]byte, []byte, []byte) {
 
 	_, priv, ch, _ := ComputeMastersFromSeed(string(seed))
@@ -131,83 +117,6 @@ func gocrypto(seed []byte) ([]byte, []byte, []byte) {
 	return HexDecode(priv), privBytes, pubBytes
 }
 
-func btcsuite(seed []byte) ([]byte, []byte, []byte) {
-	fmt.Println("HD")
-	masterKey, err := hdkeychain.NewMaster(seed, &chaincfg.MainNetParams)
-	if err != nil {
-		hmac := hmac.New(sha512.New, []byte("Bitcoin seed"))
-		hmac.Write([]byte(seed))
-		intermediary := hmac.Sum(nil)
-
-		curve := btcutil.Secp256k1()
-		curveParams := curve.Params()
-
-		// Split it into our key and chain code
-		keyBytes := intermediary[:32]
-		fmt.Printf("\t%X\n", keyBytes)
-		fmt.Printf("\t%X\n", curveParams.N.Bytes())
-		keyInt, _ := binary.ReadVarint(bytes.NewBuffer(keyBytes))
-		fmt.Printf("\t%d\n", keyInt)
-	}
-	fh := hdkeychain.HardenedKeyStart
-	k, err := masterKey.Child(uint32(fh + 44))
-	ifExit(err, 44)
-	k, err = k.Child(uint32(fh + 118))
-	ifExit(err, 118)
-	k, err = k.Child(uint32(fh + 0))
-	ifExit(err, 1)
-	k, err = k.Child(uint32(0))
-	ifExit(err, 2)
-	k, err = k.Child(uint32(0))
-	ifExit(err, 3)
-	ecpriv, err := k.ECPrivKey()
-	ifExit(err, 10)
-	ecpub, err := k.ECPubKey()
-	ifExit(err, 11)
-
-	priv := ecpriv.Serialize()
-	pub := ecpub.SerializeCompressed()
-	mkey, _ := masterKey.ECPrivKey()
-	return mkey.Serialize(), priv, pub
-}
-
-// return priv and pub
-func tylerSmith(seed []byte) ([]byte, []byte, []byte) {
-	masterKey, err := bip32.NewMasterKey(seed)
-	if err != nil {
-		hmac := hmac.New(sha512.New, []byte("Bitcoin seed"))
-		hmac.Write([]byte(seed))
-		intermediary := hmac.Sum(nil)
-
-		curve := btcutil.Secp256k1()
-		curveParams := curve.Params()
-
-		// Split it into our key and chain code
-		keyBytes := intermediary[:32]
-		fmt.Printf("\t%X\n", keyBytes)
-		fmt.Printf("\t%X\n", curveParams.N.Bytes())
-		keyInt, _ := binary.ReadVarint(bytes.NewBuffer(keyBytes))
-		fmt.Printf("\t%d\n", keyInt)
-
-	}
-	ifExit(err, 0)
-	fh := bip32.FirstHardenedChild
-	k, err := masterKey.NewChildKey(fh + 44)
-	ifExit(err, 44)
-	k, err = k.NewChildKey(fh + 118)
-	ifExit(err, 118)
-	k, err = k.NewChildKey(fh + 0)
-	ifExit(err, 1)
-	k, err = k.NewChildKey(0)
-	ifExit(err, 2)
-	k, err = k.NewChildKey(0)
-	ifExit(err, 3)
-
-	priv := k.Key
-	pub := k.PublicKey().Key
-	return masterKey.Key, priv, pub
-}
-
 // Benchmarks
 
 var revBytesCases = [][]byte{
@@ -237,6 +146,6 @@ func BenchmarkReverseBytes(b *testing.B) {
 
 	// sink is necessary to ensure if the compiler tries
 	// to smart, that it won't optimize away the benchmarks.
-	if sink != nil {
+	if sink != nil { // nolint: megacheck
 	}
 }

keys/cryptostore/holder.go

@@ -25,11 +25,13 @@ func New(coder Encoder, store keys.Storage, codec keys.Codec) Manager {
 }
 
 // exists just to make sure we fulfill the Signer interface
+// nolint [ megacheck, deadcode ]
 func (s Manager) assertSigner() keys.Signer {
 	return s
 }
 
 // exists just to make sure we fulfill the Manager interface
+// nolint [ megacheck, deadcode ]
 func (s Manager) assertKeyManager() keys.Manager {
 	return s
 }

keys/server/helpers.go

@@ -5,6 +5,8 @@ for key management, transaction signing, and query validation.
 Please read the README and godoc to see how to
 configure the server for your application.
 */
+
+// nolint: goimports
 package server
 
 import (
@@ -12,8 +14,8 @@ import (
 	"io/ioutil"
 	"net/http"
 
-	data "github.com/tendermint/go-wire/data"
 	"github.com/tendermint/go-crypto/keys/server/types"
+	data "github.com/tendermint/go-wire/data"
 
 	"github.com/pkg/errors"
 )

keys/storage/filestorage/main.go

@@ -22,8 +22,8 @@ const (
 	PrivExt   = "tlc"
 	PubExt    = "pub"
 	keyPerm   = os.FileMode(0600)
-	pubPerm   = os.FileMode(0644)
-	dirPerm   = os.FileMode(0700)
+	// pubPerm   = os.FileMode(0644)
+	dirPerm = os.FileMode(0700)
 )
 
 type FileStore struct {
@@ -43,6 +43,7 @@ func New(dir string) FileStore {
 }
 
 // assertStorage just makes sure we implement the proper Storage interface
+// nolint [ megacheck, deadcode ]
 func (s FileStore) assertStorage() keys.Storage {
 	return s
 }

keys/storage/memstorage/main.go

@@ -23,6 +23,7 @@ func New() MemStore {
 }
 
 // assertStorage just makes sure we implement the Storage interface
+// nolint [ megacheck, deadcode ]
 func (s MemStore) assertStorage() keys.Storage {
 	return s
 }

keys/wordcodec_test.go

@@ -119,8 +119,8 @@ func TestCheckInvalidLists(t *testing.T) {
 			w, err := codec.BytesToWords(data)
 			if tc.valid {
 				assert.Nil(err, "%d: %+v", i, err)
-				b, err := codec.WordsToBytes(w)
-				assert.Nil(err, "%d: %+v", i, err)
+				b, err1 := codec.WordsToBytes(w)
+				assert.Nil(err1, "%d: %+v", i, err1)
 				assert.Equal(data, b)
 			} else {
 				assert.NotNil(err, "%d", i)

keys/wordlist/wordlist.go

@@ -6,6 +6,7 @@
 // keys/wordlist/spanish.txt
 // DO NOT EDIT!
 
+// nolint: goimports
 package wordlist
 
 import (
@@ -204,9 +205,9 @@ func AssetNames() []string {
 // _bindata is a table, holding each asset generator, mapped to its name.
 var _bindata = map[string]func() (*asset, error){
 	"keys/wordlist/chinese_simplified.txt": keysWordlistChinese_simplifiedTxt,
-	"keys/wordlist/english.txt": keysWordlistEnglishTxt,
-	"keys/wordlist/japanese.txt": keysWordlistJapaneseTxt,
-	"keys/wordlist/spanish.txt": keysWordlistSpanishTxt,
+	"keys/wordlist/english.txt":            keysWordlistEnglishTxt,
+	"keys/wordlist/japanese.txt":           keysWordlistJapaneseTxt,
+	"keys/wordlist/spanish.txt":            keysWordlistSpanishTxt,
 }
 
 // AssetDir returns the file names below a certain
@@ -248,13 +249,14 @@ type bintree struct {
 	Func     func() (*asset, error)
 	Children map[string]*bintree
 }
+
 var _bintree = &bintree{nil, map[string]*bintree{
 	"keys": &bintree{nil, map[string]*bintree{
 		"wordlist": &bintree{nil, map[string]*bintree{
 			"chinese_simplified.txt": &bintree{keysWordlistChinese_simplifiedTxt, map[string]*bintree{}},
-			"english.txt": &bintree{keysWordlistEnglishTxt, map[string]*bintree{}},
-			"japanese.txt": &bintree{keysWordlistJapaneseTxt, map[string]*bintree{}},
-			"spanish.txt": &bintree{keysWordlistSpanishTxt, map[string]*bintree{}},
+			"english.txt":            &bintree{keysWordlistEnglishTxt, map[string]*bintree{}},
+			"japanese.txt":           &bintree{keysWordlistJapaneseTxt, map[string]*bintree{}},
+			"spanish.txt":            &bintree{keysWordlistSpanishTxt, map[string]*bintree{}},
 		}},
 	}},
 }}
@@ -305,4 +307,3 @@ func _filePath(dir, name string) string {
 	cannonicalName := strings.Replace(name, "\\", "/", -1)
 	return filepath.Join(append([]string{dir}, strings.Split(cannonicalName, "/")...)...)
 }
-