linter: enable SA4018 and SA4004

build/BUILD.bazel

@@ -61,7 +61,9 @@ STATICHECK_ANALYZERS = [
     "SA2003",
     "SA3000",
     "SA3001",
+    "SA4004",
     "SA4009",
+    "SA4018",
     "SA5000",
     "SA5001",
     "SA5002",

build/nogo_config.json

@@ -1023,13 +1023,28 @@
       ".*_generated\\.go$": "ignore generated code"
     }
   },
+  "SA4004": {
+    "exclude_files": {
+      "parser/parser.go": "parser/parser.go code",
+      "server/http_status.go": "ignore server/http_status.go",
+      "external/": "no need to vet third party code",
+      ".*_generated\\.go$": "ignore generated code"
+    }
+  },
   "SA4009": {
     "exclude_files": {
       "parser/parser.go": "parser/parser.go code",
       "external/": "no need to vet third party code",
       ".*_generated\\.go$": "ignore generated code"
     }
   },
+  "SA4018": {
+    "exclude_files": {
+      "parser/parser.go": "parser/parser.go code",
+      "external/": "no need to vet third party code",
+      ".*_generated\\.go$": "ignore generated code"
+    }
+  },
   "SA5000": {
     "exclude_files": {
       "parser/parser.go": "parser/parser.go code",

store/mockstore/unistore/tikv/mvcc/tikv.go

@@ -129,52 +129,3 @@ const (
 )
 
 var errInvalidLockCFValue = errors.New("invalid lock CF value")
-
-// ParseLockCFValue parses the []byte data and returns a MvccLock.
-func ParseLockCFValue(data []byte) (lock Lock, err error) {
-	if len(data) == 0 {
-		err = errInvalidLockCFValue
-		return
-	}
-	switch data[0] {
-	case LockTypePut:
-		lock.Op = byte(kvrpcpb.Op_Put)
-	case LockTypeDelete:
-		lock.Op = byte(kvrpcpb.Op_Del)
-	case LockTypeLock:
-		lock.Op = byte(kvrpcpb.Op_Lock)
-	case LockTypePessimistic:
-		lock.Op = byte(kvrpcpb.Op_PessimisticLock)
-	default:
-		err = errInvalidLockCFValue
-		return
-	}
-	data, lock.Primary, err = codec.DecodeCompactBytes(data[1:])
-	if err != nil {
-		return
-	}
-	lock.PrimaryLen = uint16(len(lock.Primary))
-	data, lock.StartTS, err = codec.DecodeUvarint(data)
-	if err != nil || len(data) == 0 {
-		return
-	}
-	var ttl uint64
-	data, ttl, err = codec.DecodeUvarint(data)
-	lock.TTL = uint32(ttl)
-	if err != nil || len(data) == 0 {
-		return
-	}
-	if data[0] == shortValuePrefix {
-		shortValLen := int(data[1])
-		data = data[2:]
-		lock.Value = data[:shortValLen]
-		data = data[shortValLen:]
-	}
-	if len(data) > 0 && data[0] == forUpdatePrefix {
-		data, lock.ForUpdateTS, err = codec.DecodeUint(data[1:])
-	}
-	if len(data) > 0 && data[0] == minCommitTsPrefix {
-		data, lock.MinCommitTS, err = codec.DecodeUint(data[1:])
-	}
-	return
-}

util/dbutil/common.go

@@ -606,7 +606,7 @@ func GetTidbLatestTSO(ctx context.Context, db QueryExecutor) (int64, error) {
 	}
 	defer rows.Close()
 
-	for rows.Next() {
+	if rows.Next() {
 		fields, err1 := ScanRow(rows)
 		if err1 != nil {
 			return 0, errors.Trace(err1)
@@ -648,12 +648,11 @@ func GetDBVersion(ctx context.Context, db QueryExecutor) (string, error) {
 	defer result.Close()
 
 	var version sql.NullString
-	for result.Next() {
+	if result.Next() {
 		err := result.Scan(&version)
 		if err != nil {
 			return "", errors.Trace(err)
 		}
-		break
 	}
 
 	if version.Valid {