fix golint issues in core/stringx (#516)

core/stringx/random.go

@@ -42,10 +42,12 @@ func (ls *lockedSource) Seed(seed int64) {
 	ls.source.Seed(seed)
 }
 
+// Rand returns a random string.
 func Rand() string {
 	return Randn(defaultRandLen)
 }
 
+// RandId returns a random id string.
 func RandId() string {
 	b := make([]byte, idLen)
 	_, err := crand.Read(b)
@@ -56,6 +58,7 @@ func RandId() string {
 	return fmt.Sprintf("%x%x%x%x", b[0:2], b[2:4], b[4:6], b[6:8])
 }
 
+// Randn returns a random string with length n.
 func Randn(n int) string {
 	b := make([]byte, n)
 	// A src.Int63() generates 63 random bits, enough for letterIdxMax characters!
@@ -74,6 +77,7 @@ func Randn(n int) string {
 	return string(b)
 }
 
+// Seed sets the seed to seed.
 func Seed(seed int64) {
 	src.Seed(seed)
 }

core/stringx/replacer.go

@@ -3,6 +3,7 @@ package stringx
 import "strings"
 
 type (
+	// Replacer interface wraps the Replace method.
 	Replacer interface {
 		Replace(text string) string
 	}
@@ -13,6 +14,7 @@ type (
 	}
 )
 
+// NewReplacer returns a Replacer.
 func NewReplacer(mapping map[string]string) Replacer {
 	var rep = &replacer{
 		mapping: mapping,

core/stringx/strings.go

@@ -7,10 +7,13 @@ import (
 )
 
 var (
+	// ErrInvalidStartPosition is an error that indicates the start position is invalid.
 	ErrInvalidStartPosition = errors.New("start position is invalid")
-	ErrInvalidStopPosition  = errors.New("stop position is invalid")
+	// ErrInvalidStopPosition is an error that indicates the stop position is invalid.
+	ErrInvalidStopPosition = errors.New("stop position is invalid")
 )
 
+// Contains checks if str is in list.
 func Contains(list []string, str string) bool {
 	for _, each := range list {
 		if each == str {
@@ -21,6 +24,7 @@ func Contains(list []string, str string) bool {
 	return false
 }
 
+// Filter filters chars from s with given filter function.
 func Filter(s string, filter func(r rune) bool) string {
 	var n int
 	chars := []rune(s)
@@ -36,6 +40,7 @@ func Filter(s string, filter func(r rune) bool) string {
 	return string(chars[:n])
 }
 
+// HasEmpty checks if there are empty strings in args.
 func HasEmpty(args ...string) bool {
 	for _, arg := range args {
 		if len(arg) == 0 {
@@ -46,10 +51,12 @@ func HasEmpty(args ...string) bool {
 	return false
 }
 
+// NotEmpty checks if all strings are not empty in args.
 func NotEmpty(args ...string) bool {
 	return !HasEmpty(args...)
 }
 
+// Remove removes given strs from strings.
 func Remove(strings []string, strs ...string) []string {
 	out := append([]string(nil), strings...)
 
@@ -67,6 +74,7 @@ func Remove(strings []string, strs ...string) []string {
 	return out
 }
 
+// Reverse reverses s.
 func Reverse(s string) string {
 	runes := []rune(s)
 
@@ -77,7 +85,7 @@ func Reverse(s string) string {
 	return string(runes)
 }
 
-// Substr returns runes between start and stop [start, stop) regardless of the chars are ascii or utf8
+// Substr returns runes between start and stop [start, stop) regardless of the chars are ascii or utf8.
 func Substr(str string, start int, stop int) (string, error) {
 	rs := []rune(str)
 	length := len(rs)
@@ -93,6 +101,7 @@ func Substr(str string, start int, stop int) (string, error) {
 	return string(rs[start:stop]), nil
 }
 
+// TakeOne returns valid string if not empty or later one.
 func TakeOne(valid, or string) string {
 	if len(valid) > 0 {
 		return valid
@@ -101,6 +110,7 @@ func TakeOne(valid, or string) string {
 	return or
 }
 
+// TakeWithPriority returns the first not empty result from fns.
 func TakeWithPriority(fns ...func() string) string {
 	for _, fn := range fns {
 		val := fn()
@@ -112,6 +122,7 @@ func TakeWithPriority(fns ...func() string) string {
 	return ""
 }
 
+// Union merges the strings in first and second.
 func Union(first, second []string) []string {
 	set := make(map[string]lang.PlaceholderType)
 

core/stringx/trie.go

@@ -5,8 +5,10 @@ import "github.com/tal-tech/go-zero/core/lang"
 const defaultMask = '*'
 
 type (
+	// TrieOption defines the method to customize a Trie.
 	TrieOption func(trie *trieNode)
 
+	// A Trie is a tree implementation that used to find elements rapidly.
 	Trie interface {
 		Filter(text string) (string, []string, bool)
 		FindKeywords(text string) []string
@@ -23,6 +25,7 @@ type (
 	}
 )
 
+// NewTrie returns a Trie.
 func NewTrie(words []string, opts ...TrieOption) Trie {
 	n := new(trieNode)
 
@@ -130,6 +133,7 @@ func (n *trieNode) replaceWithAsterisk(chars []rune, start, stop int) {
 	}
 }
 
+// WithMask customizes a Trie with keywords masked as given mask char.
 func WithMask(mask rune) TrieOption {
 	return func(n *trieNode) {
 		n.mask = mask