Files
gitea/modules/base/natural_sort_test.go
SEONGHYUN HONG 84b67d50a6 fix(base): correct natural sort of numbers with leading zeros (#38163)
### Description

`NaturalSortCompare` (`modules/base/natural_sort.go`) compares two
numeric run parts by **raw string length**:

```go
if len(part1) != len(part2) {
    return len(part1) - len(part2)
}
```

"Longer digit string = larger number" only holds without leading zeros.
With zero-padded numbers the comparison inverts:

- `file0001` vs `file2` → claims `file0001 > file2`, but `1 < 2`
- `a08` vs `a9` → claims `a08 > a9`, but `8 < 9`

This affects any natural-ordered listing where zero-padded and shorter
unpadded numbers mix (branch/tag/file names, etc.).

### Fix

Strip leading zeros before comparing digit-count magnitude; on equal
magnitude fall back to collation, then to the original length so fewer
leading zeros sort first. Added a small `naturalSortTrimZeros` helper
(keeps one char so `"000"` → `"0"`).

Signed-off-by: Seonghyun Hong <s3onghyun.hong@gmail.com>
Signed-off-by: wxiaoguang <wxiaoguang@gmail.com>
Co-authored-by: silverwind <me@silverwind.io>
Co-authored-by: wxiaoguang <wxiaoguang@gmail.com>
2026-08-22 09:40:49 +00:00

49 lines
1.0 KiB
Go

// Copyright 2017 The Gitea Authors. All rights reserved.
// SPDX-License-Identifier: MIT
package base
import (
"testing"
"github.com/stretchr/testify/assert"
)
func TestNaturalSortLess(t *testing.T) {
testLess := func(s1, s2 string) {
assert.Negative(t, NaturalSortCompare(s1, s2), "s1<s2 should be true: s1=%q, s2=%q", s1, s2)
}
testEqual := func(s1, s2 string) {
assert.Zero(t, NaturalSortCompare(s1, s2), "s1<s2 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")
testLess("file0001", "file2")
testLess("a8", "a08")
testLess("00", "1")
testLess("0", "00") // equal value, fewer leading zeros sorts first
}