chore: remove usages of sort.Sort (#6689)

improve language stats rounding:

- Add tests (I had to omit some edge cases as the current method is
non-determistic in some cases, due to random order of map access).
- Document the algorithm used.
- Lower the amount of calculations that need to be done.
- Because of the aforementioned non-determistic don't use stable sort
and instead regular sort.

better sorting for `RepositoryList`:

- Add testing
- Use `slices.Sortfunc` instead of `sort.Sort`.
- Remove the methods needed for `sort.Sort`.

better git tag sorter:

- Use `slices.SortFunc` instead of `sort.Sort`.
- Remove `tagSorter` and its related methods.
- Added testing.

Reviewed-on: https://codeberg.org/forgejo/forgejo/pulls/6689
Reviewed-by: Earl Warren <earl-warren@noreply.codeberg.org>
Co-authored-by: Gusted <postmaster@gusted.xyz>
Co-committed-by: Gusted <postmaster@gusted.xyz>

modules/git/repo_tag.go

@@ -9,6 +9,7 @@ import (
 	"errors"
 	"fmt"
 	"io"
+	"slices"
 	"strings"
 
 	"code.gitea.io/gitea/modules/git/foreachref"
@@ -153,7 +154,9 @@ func (repo *Repository) GetTagInfos(page, pageSize int) ([]*Tag, int, error) {
 		return nil, 0, fmt.Errorf("GetTagInfos: parse output: %w", err)
 	}
 
-	sortTagsByTime(tags)
+	slices.SortFunc(tags, func(b, a *Tag) int {
+		return a.Tagger.When.Compare(b.Tagger.When)
+	})
 	tagsTotal := len(tags)
 	if page != 0 {
 		tags = util.PaginateSlice(tags, page, pageSize).([]*Tag)

modules/git/repo_tag_test.go

@@ -6,6 +6,7 @@ package git
 import (
 	"path/filepath"
 	"testing"
+	"time"
 
 	"github.com/stretchr/testify/assert"
 	"github.com/stretchr/testify/require"
@@ -30,9 +31,11 @@ func TestRepository_GetTags(t *testing.T) {
 	assert.EqualValues(t, "signed-tag", tags[0].Name)
 	assert.EqualValues(t, "36f97d9a96457e2bab511db30fe2db03893ebc64", tags[0].ID.String())
 	assert.EqualValues(t, "tag", tags[0].Type)
+	assert.EqualValues(t, time.Date(2022, time.November, 13, 16, 40, 20, 0, time.FixedZone("", 3600)), tags[0].Tagger.When)
 	assert.EqualValues(t, "test", tags[1].Name)
 	assert.EqualValues(t, "3ad28a9149a2864384548f3d17ed7f38014c9e8a", tags[1].ID.String())
 	assert.EqualValues(t, "tag", tags[1].Type)
+	assert.EqualValues(t, time.Date(2018, time.June, 16, 20, 13, 18, 0, time.FixedZone("", -25200)), tags[1].Tagger.When)
 }
 
 func TestRepository_GetTag(t *testing.T) {

modules/git/tag.go

@@ -5,7 +5,6 @@ package git
 
 import (
 	"bytes"
-	"sort"
 	"strings"
 
 	api "code.gitea.io/gitea/modules/structs"
@@ -107,23 +106,3 @@ l:
 
 	return tag, nil
 }
-
-type tagSorter []*Tag
-
-func (ts tagSorter) Len() int {
-	return len([]*Tag(ts))
-}
-
-func (ts tagSorter) Less(i, j int) bool {
-	return []*Tag(ts)[i].Tagger.When.After([]*Tag(ts)[j].Tagger.When)
-}
-
-func (ts tagSorter) Swap(i, j int) {
-	[]*Tag(ts)[i], []*Tag(ts)[j] = []*Tag(ts)[j], []*Tag(ts)[i]
-}
-
-// sortTagsByTime
-func sortTagsByTime(tags []*Tag) {
-	sorter := tagSorter(tags)
-	sort.Sort(sorter)
-}