Fix natural sort (#31384) (#31394)

Backport #31384 by wxiaoguang

Fix #31374

Co-authored-by: wxiaoguang <wxiaoguang@gmail.com>

diff --git a/modules/base/natural_sort.go b/modules/base/natural_sort.go
index 0f90ec70cef44f3ea248c9b9c8a9cb259a90d598..acb90022764569933a512a60d064c3cbd33bbcec 100644 (file)
--- a/modules/base/natural_sort.go
+++ b/modules/base/natural_sort.go
@@ -4,12 +4,67 @@
 package base
 
 import (
+       "unicode/utf8"
+
        "golang.org/x/text/collate"
        "golang.org/x/text/language"
 )
 
+func naturalSortGetRune(str string, pos int) (r rune, size int, has bool) {
+       if pos >= len(str) {
+               return 0, 0, false
+       }
+       r, size = utf8.DecodeRuneInString(str[pos:])
+       if r == utf8.RuneError {
+               r, size = rune(str[pos]), 1 // if invalid input, treat it as a single byte ascii
+       }
+       return r, size, true
+}
+
+func naturalSortAdvance(str string, pos int) (end int, isNumber bool) {
+       end = pos
+       for {
+               r, size, has := naturalSortGetRune(str, end)
+               if !has {
+                       break
+               }
+               isCurRuneNum := '0' <= r && r <= '9'
+               if end == pos {
+                       isNumber = isCurRuneNum
+                       end += size
+               } else if isCurRuneNum == isNumber {
+                       end += size
+               } else {
+                       break
+               }
+       }
+       return end, isNumber
+}
+
 // NaturalSortLess compares two strings so that they could be sorted in natural order
 func NaturalSortLess(s1, s2 string) bool {
+       // There is a bug in Golang's collate package: https://github.com/golang/go/issues/67997
+       // text/collate: CompareString(collate.Numeric) returns wrong result for "0.0" vs "1.0" #67997
+       // So we need to handle the number parts by ourselves
        c := collate.New(language.English, collate.Numeric)
-       return c.CompareString(s1, s2) < 0
+       pos1, pos2 := 0, 0
+       for pos1 < len(s1) && pos2 < len(s2) {
+               end1, isNum1 := naturalSortAdvance(s1, pos1)
+               end2, isNum2 := naturalSortAdvance(s2, pos2)
+               part1, part2 := s1[pos1:end1], s2[pos2:end2]
+               if isNum1 && isNum2 {
+                       if part1 != part2 {
+                               if len(part1) != len(part2) {
+                                       return len(part1) < len(part2)
+                               }
+                               return part1 < part2
+                       }
+               } else {
+                       if cmp := c.CompareString(part1, part2); cmp != 0 {
+                               return cmp < 0
+                       }
+               }
+               pos1, pos2 = end1, end2
+       }
+       return len(s1) < len(s2)
 }

diff --git a/modules/base/natural_sort_test.go b/modules/base/natural_sort_test.go
index f27a4eb53a249da8754f4a519cb36d1d432c08a9..b001bc4ac97d5419f1ff973baa093f650499282d 100644 (file)
--- a/modules/base/natural_sort_test.go
+++ b/modules/base/natural_sort_test.go
@@ -10,21 +10,36 @@ import (
 )
 
 func TestNaturalSortLess(t *testing.T) {
-       test := func(s1, s2 string, less bool) {
-               assert.Equal(t, less, NaturalSortLess(s1, s2), "s1=%q, s2=%q", s1, s2)
+       testLess := func(s1, s2 string) {
+               assert.True(t, NaturalSortLess(s1, s2), "s1<s2 should be true: s1=%q, s2=%q", s1, s2)
+               assert.False(t, NaturalSortLess(s2, s1), "s2<s1 should be false: s1=%q, s2=%q", s1, s2)
        }
-       test("v1.20.0", "v1.2.0", false)
-       test("v1.20.0", "v1.29.0", true)
-       test("v1.20.0", "v1.20.0", false)
-       test("abc", "bcd", true)
-       test("a-1-a", "a-1-b", true)
-       test("2", "12", true)
-       test("a", "ab", true)
-
-       test("A", "b", true)
-       test("a", "B", true)
-
-       test("cafe", "café", true)
-       test("café", "cafe", false)
-       test("caff", "café", false)
+       testEqual := func(s1, s2 string) {
+               assert.False(t, NaturalSortLess(s1, s2), "s1<s2 should be false: s1=%q, s2=%q", s1, s2)
+               assert.False(t, NaturalSortLess(s2, s1), "s2<s1 should be false: s1=%q, s2=%q", s1, s2)
+       }
+
+       testEqual("", "")
+       testLess("", "a")
+       testLess("", "1")
+
+       testLess("v1.2", "v1.2.0")
+       testLess("v1.2.0", "v1.10.0")
+       testLess("v1.20.0", "v1.29.0")
+       testEqual("v1.20.0", "v1.20.0")
+
+       testLess("a", "A")
+       testLess("a", "B")
+       testLess("A", "b")
+       testLess("A", "ab")
+
+       testLess("abc", "bcd")
+       testLess("a-1-a", "a-1-b")
+       testLess("2", "12")
+
+       testLess("cafe", "café")
+       testLess("café", "caff")
+
+       testLess("A-2", "A-11")
+       testLess("0.txt", "1.txt")
 }