Sort repository tree entries in natural way (#2506)

* Sort repository tree entries in natural way

* Fix sort for different length strings with first parts equal

* Improve test case

* Refactor return statements

* Update gitea/git dependency

modules/base/natural_sort.go

@@ -0,0 +1,89 @@
+// Copyright 2017 The Gitea Authors. All rights reserved.
+// Use of this source code is governed by a MIT-style
+// license that can be found in the LICENSE file.
+
+package base
+
+import (
+	"math/big"
+	"unicode/utf8"
+)
+
+// NaturalSortLess compares two strings so that they could be sorted in natural order
+func NaturalSortLess(s1, s2 string) bool {
+	var i1, i2 int
+	for {
+		rune1, j1, end1 := getNextRune(s1, i1)
+		rune2, j2, end2 := getNextRune(s2, i2)
+		if end1 || end2 {
+			return end1 != end2 && end1
+		}
+		dec1 := isDecimal(rune1)
+		dec2 := isDecimal(rune2)
+		var less, equal bool
+		if dec1 && dec2 {
+			i1, i2, less, equal = compareByNumbers(s1, i1, s2, i2)
+		} else if !dec1 && !dec2 {
+			equal = rune1 == rune2
+			less = rune1 < rune2
+			i1 = j1
+			i2 = j2
+		} else {
+			return rune1 < rune2
+		}
+		if !equal {
+			return less
+		}
+	}
+}
+
+func getNextRune(str string, pos int) (rune, int, bool) {
+	if pos < len(str) {
+		r, w := utf8.DecodeRuneInString(str[pos:])
+		// Fallback to ascii
+		if r == utf8.RuneError {
+			r = rune(str[pos])
+			w = 1
+		}
+		return r, pos + w, false
+	}
+	return 0, pos, true
+}
+
+func isDecimal(r rune) bool {
+	return '0' <= r && r <= '9'
+}
+
+func compareByNumbers(str1 string, pos1 int, str2 string, pos2 int) (i1, i2 int, less, equal bool) {
+	var d1, d2 bool = true, true
+	var dec1, dec2 string
+	for d1 || d2 {
+		if d1 {
+			r, j, end := getNextRune(str1, pos1)
+			if !end && isDecimal(r) {
+				dec1 += string(r)
+				pos1 = j
+			} else {
+				d1 = false
+			}
+		}
+		if d2 {
+			r, j, end := getNextRune(str2, pos2)
+			if !end && isDecimal(r) {
+				dec2 += string(r)
+				pos2 = j
+			} else {
+				d2 = false
+			}
+		}
+	}
+	less, equal = compareBigNumbers(dec1, dec2)
+	return pos1, pos2, less, equal
+}
+
+func compareBigNumbers(dec1, dec2 string) (less, equal bool) {
+	d1, _ := big.NewInt(0).SetString(dec1, 10)
+	d2, _ := big.NewInt(0).SetString(dec2, 10)
+	cmp := d1.Cmp(d2)
+	return cmp < 0, cmp == 0
+}

modules/base/natural_sort_test.go

@@ -0,0 +1,24 @@
+// Copyright 2017 The Gitea Authors. All rights reserved.
+// Use of this source code is governed by a MIT-style
+// license that can be found in the LICENSE file.
+
+package base
+
+import (
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+)
+
+func TestNaturalSortLess(t *testing.T) {
+	test := func(s1, s2 string, less bool) {
+		assert.Equal(t, less, NaturalSortLess(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", "abc" < "bcd")
+	test("a-1-a", "a-1-b", true)
+	test("2", "12", true)
+	test("a", "ab", "a" < "ab")
+}

routers/repo/view.go

@@ -47,7 +47,7 @@ func renderDirectory(ctx *context.Context, treeLink string) {
 		ctx.Handle(500, "ListEntries", err)
 		return
 	}
-	entries.Sort()
+	entries.CustomSort(base.NaturalSortLess)
 
 	ctx.Data["Files"], err = entries.GetCommitsInfo(ctx.Repo.Commit, ctx.Repo.TreePath)
 	if err != nil {

vendor/code.gitea.io/git/tree_entry.go

@@ -116,35 +116,51 @@ func (te *TreeEntry) GetSubJumpablePathName() string {
 // Entries a list of entry
 type Entries []*TreeEntry
 
-var sorter = []func(t1, t2 *TreeEntry) bool{
-	func(t1, t2 *TreeEntry) bool {
+type customSortableEntries struct {
+	Comparer func(s1, s2 string) bool
+	Entries
+}
+
+var sorter = []func(t1, t2 *TreeEntry, cmp func(s1, s2 string) bool) bool{
+	func(t1, t2 *TreeEntry, cmp func(s1, s2 string) bool) bool {
 		return (t1.IsDir() || t1.IsSubModule()) && !t2.IsDir() && !t2.IsSubModule()
 	},
-	func(t1, t2 *TreeEntry) bool {
-		return t1.name < t2.name
+	func(t1, t2 *TreeEntry, cmp func(s1, s2 string) bool) bool {
+		return cmp(t1.name, t2.name)
 	},
 }
 
-func (tes Entries) Len() int      { return len(tes) }
-func (tes Entries) Swap(i, j int) { tes[i], tes[j] = tes[j], tes[i] }
-func (tes Entries) Less(i, j int) bool {
-	t1, t2 := tes[i], tes[j]
+func (ctes customSortableEntries) Len() int { return len(ctes.Entries) }
+
+func (ctes customSortableEntries) Swap(i, j int) {
+	ctes.Entries[i], ctes.Entries[j] = ctes.Entries[j], ctes.Entries[i]
+}
+
+func (ctes customSortableEntries) Less(i, j int) bool {
+	t1, t2 := ctes.Entries[i], ctes.Entries[j]
 	var k int
 	for k = 0; k < len(sorter)-1; k++ {
 		s := sorter[k]
 		switch {
-		case s(t1, t2):
+		case s(t1, t2, ctes.Comparer):
 			return true
-		case s(t2, t1):
+		case s(t2, t1, ctes.Comparer):
 			return false
 		}
 	}
-	return sorter[k](t1, t2)
+	return sorter[k](t1, t2, ctes.Comparer)
 }
 
 // Sort sort the list of entry
 func (tes Entries) Sort() {
-	sort.Sort(tes)
+	sort.Sort(customSortableEntries{func(s1, s2 string) bool {
+		return s1 < s2
+	}, tes})
+}
+
+// CustomSort customizable string comparing sort entry list
+func (tes Entries) CustomSort(cmp func(s1, s2 string) bool) {
+	sort.Sort(customSortableEntries{cmp, tes})
 }
 
 type commitInfo struct {

vendor/vendor.json

@@ -3,10 +3,10 @@
 	"ignore": "test appengine",
 	"package": [
 		{
-			"checksumSHA1": "fR5YDSoG7xYv2aLO23rne95gWps=",
+			"checksumSHA1": "9dxw/SGpdhNNm704gt6F02ItYtQ=",
 			"path": "code.gitea.io/git",
-			"revision": "479f87e5d189e7b8f1fd51dbcd25faa32b632cd2",
-			"revisionTime": "2017-08-03T00:53:29Z"
+			"revision": "d7487da878e40ee6c4fac7280b518c0ed0be702c",
+			"revisionTime": "2017-09-16T17:49:37Z"
 		},
 		{
 			"checksumSHA1": "Zgp5RqU+20L2p9TNl1rSsUIWEEE=",