refactor: rename files *_util.go to *_internal.go

strutil/string_util.go

@@ -1,40 +0,0 @@
-package strutil
-
-import "strings"
-
-// splitWordsToLower split a string into worlds by uppercase char
-func splitWordsToLower(s string) []string {
-	var res []string
-
-	upperIndexes := upperIndex(s)
-	l := len(upperIndexes)
-	if upperIndexes == nil || l == 0 {
-		if s != "" {
-			res = append(res, s)
-		}
-		return res
-	}
-	for i := 0; i < l; i++ {
-		if i < l-1 {
-			res = append(res, strings.ToLower(s[upperIndexes[i]:upperIndexes[i+1]]))
-		} else {
-			res = append(res, strings.ToLower(s[upperIndexes[i]:]))
-		}
-	}
-	return res
-}
-
-// upperIndex get a int slice which elements are all the uppercase char index of a string
-func upperIndex(s string) []int {
-	var res []int
-	for i := 0; i < len(s); i++ {
-		if 64 < s[i] && s[i] < 91 {
-			res = append(res, i)
-		}
-	}
-	if len(s) > 0 && res != nil && res[0] != 0 {
-		res = append([]int{0}, res...)
-	}
-
-	return res
-}