services/repository: fix ListUnadoptedRepositories incorrect total count (#17865)

The total count returned by ListUnadoptedRepositories is incorrectly
calculated.

The code snippet within ListUnadoptedRepositories used to verify
unadopted repositories is repeated three times in the function. It is
moved in the checkUnadoptedRepositories function and a unit test is
added to verify it works as expected.

A unit test is added to verify the total count returned by
ListUnadoptedRepositories is as expected.

Signed-off-by: singuliere <singuliere@autistici.org>

2 files changed, 156 insertions, 110 deletions

diff --git a/services/repository/adopt.go b/services/repository/adopt.go
index 2f87b0d7bd..fc3fdc608f 100644
--- a/services/repository/adopt.go
+++ b/services/repository/adopt.go
@@ -217,6 +217,57 @@ func DeleteUnadoptedRepository(doer, u *user_model.User, repoName string) error
 	return util.RemoveAll(repoPath)
 }
 
+type unadoptedRrepositories struct {
+	repositories []string
+	index        int
+	start        int
+	end          int
+}
+
+func (unadopted *unadoptedRrepositories) add(repository string) {
+	if unadopted.index >= unadopted.start && unadopted.index < unadopted.end {
+		unadopted.repositories = append(unadopted.repositories, repository)
+	}
+	unadopted.index++
+}
+
+func checkUnadoptedRepositories(userName string, repoNamesToCheck []string, unadopted *unadoptedRrepositories) error {
+	if len(repoNamesToCheck) == 0 {
+		return nil
+	}
+	ctxUser, err := user_model.GetUserByName(userName)
+	if err != nil {
+		if user_model.IsErrUserNotExist(err) {
+			log.Debug("Missing user: %s", userName)
+			return nil
+		}
+		return err
+	}
+	repos, _, err := models.GetUserRepositories(&models.SearchRepoOptions{
+		Actor:   ctxUser,
+		Private: true,
+		ListOptions: db.ListOptions{
+			Page:     1,
+			PageSize: len(repoNamesToCheck),
+		}, LowerNames: repoNamesToCheck})
+	if err != nil {
+		return err
+	}
+	if len(repos) == len(repoNamesToCheck) {
+		return nil
+	}
+	repoNames := make(map[string]bool, len(repos))
+	for _, repo := range repos {
+		repoNames[repo.LowerName] = true
+	}
+	for _, repoName := range repoNamesToCheck {
+		if _, ok := repoNames[repoName]; !ok {
+			unadopted.add(filepath.Join(userName, repoName))
+		}
+	}
+	return nil
+}
+
 // ListUnadoptedRepositories lists all the unadopted repositories that match the provided query
 func ListUnadoptedRepositories(query string, opts *db.ListOptions) ([]string, int, error) {
 	globUser, _ := glob.Compile("*")
@@ -236,15 +287,17 @@ func ListUnadoptedRepositories(query string, opts *db.ListOptions) ([]string, in
 			}
 		}
 	}
-	start := (opts.Page - 1) * opts.PageSize
-	end := start + opts.PageSize
-
-	repoNamesToCheck := make([]string, 0, opts.PageSize)
+	var repoNamesToCheck []string
 
-	repoNames := make([]string, 0, opts.PageSize)
-	var ctxUser *user_model.User
+	start := (opts.Page - 1) * opts.PageSize
+	unadopted := &unadoptedRrepositories{
+		repositories: make([]string, 0, opts.PageSize),
+		start:        start,
+		end:          start + opts.PageSize,
+		index:        0,
+	}
 
-	count := 0
+	var userName string
 
 	// We're going to iterate by pagesize.
 	root := filepath.Clean(setting.RepoRootPath)
@@ -258,51 +311,16 @@ func ListUnadoptedRepositories(query string, opts *db.ListOptions) ([]string, in
 
 		if !strings.ContainsRune(path[len(root)+1:], filepath.Separator) {
 			// Got a new user
-
-			// Clean up old repoNamesToCheck
-			if len(repoNamesToCheck) > 0 {
-				repos, _, err := models.GetUserRepositories(&models.SearchRepoOptions{
-					Actor:   ctxUser,
-					Private: true,
-					ListOptions: db.ListOptions{
-						Page:     1,
-						PageSize: opts.PageSize,
-					}, LowerNames: repoNamesToCheck})
-				if err != nil {
-					return err
-				}
-				for _, name := range repoNamesToCheck {
-					found := false
-				repoLoopCatchup:
-					for i, repo := range repos {
-						if repo.LowerName == name {
-							found = true
-							repos = append(repos[:i], repos[i+1:]...)
-							break repoLoopCatchup
-						}
-					}
-					if !found {
-						if count >= start && count < end {
-							repoNames = append(repoNames, fmt.Sprintf("%s/%s", ctxUser.Name, name))
-						}
-						count++
-					}
-				}
-				repoNamesToCheck = repoNamesToCheck[:0]
+			if err = checkUnadoptedRepositories(userName, repoNamesToCheck, unadopted); err != nil {
+				return err
 			}
+			repoNamesToCheck = repoNamesToCheck[:0]
 
 			if !globUser.Match(info.Name()) {
 				return filepath.SkipDir
 			}
 
-			ctxUser, err = user_model.GetUserByName(info.Name())
-			if err != nil {
-				if user_model.IsErrUserNotExist(err) {
-					log.Debug("Missing user: %s", info.Name())
-					return filepath.SkipDir
-				}
-				return err
-			}
+			userName = info.Name()
 			return nil
 		}
 
@@ -315,74 +333,16 @@ func ListUnadoptedRepositories(query string, opts *db.ListOptions) ([]string, in
 		if repo_model.IsUsableRepoName(name) != nil || strings.ToLower(name) != name || !globRepo.Match(name) {
 			return filepath.SkipDir
 		}
-		if count < end {
-			repoNamesToCheck = append(repoNamesToCheck, name)
-			if len(repoNamesToCheck) >= opts.PageSize {
-				repos, _, err := models.GetUserRepositories(&models.SearchRepoOptions{
-					Actor:   ctxUser,
-					Private: true,
-					ListOptions: db.ListOptions{
-						Page:     1,
-						PageSize: opts.PageSize,
-					}, LowerNames: repoNamesToCheck})
-				if err != nil {
-					return err
-				}
-				for _, name := range repoNamesToCheck {
-					found := false
-				repoLoop:
-					for i, repo := range repos {
-						if repo.LowerName == name {
-							found = true
-							repos = append(repos[:i], repos[i+1:]...)
-							break repoLoop
-						}
-					}
-					if !found {
-						if count >= start && count < end {
-							repoNames = append(repoNames, fmt.Sprintf("%s/%s", ctxUser.Name, name))
-						}
-						count++
-					}
-				}
-				repoNamesToCheck = repoNamesToCheck[:0]
-			}
-			return filepath.SkipDir
-		}
-		count++
+
+		repoNamesToCheck = append(repoNamesToCheck, name)
 		return filepath.SkipDir
 	}); err != nil {
 		return nil, 0, err
 	}
 
-	if len(repoNamesToCheck) > 0 {
-		repos, _, err := models.GetUserRepositories(&models.SearchRepoOptions{
-			Actor:   ctxUser,
-			Private: true,
-			ListOptions: db.ListOptions{
-				Page:     1,
-				PageSize: opts.PageSize,
-			}, LowerNames: repoNamesToCheck})
-		if err != nil {
-			return nil, 0, err
-		}
-		for _, name := range repoNamesToCheck {
-			found := false
-		repoLoop:
-			for i, repo := range repos {
-				if repo.LowerName == name {
-					found = true
-					repos = append(repos[:i], repos[i+1:]...)
-					break repoLoop
-				}
-			}
-			if !found {
-				if count >= start && count < end {
-					repoNames = append(repoNames, fmt.Sprintf("%s/%s", ctxUser.Name, name))
-				}
-				count++
-			}
-		}
+	if err := checkUnadoptedRepositories(userName, repoNamesToCheck, unadopted); err != nil {
+		return nil, 0, err
 	}
-	return repoNames, count, nil
+
+	return unadopted.repositories, unadopted.index, nil
 }
diff --git a/services/repository/adopt_test.go b/services/repository/adopt_test.go
new file mode 100644
index 0000000000..2053151106
--- /dev/null
+++ b/services/repository/adopt_test.go
@@ -0,0 +1,86 @@
+// Copyright 2021 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 repository
+
+import (
+	"os"
+	"path"
+	"testing"
+
+	"code.gitea.io/gitea/models/db"
+	"code.gitea.io/gitea/models/unittest"
+	"code.gitea.io/gitea/modules/setting"
+
+	"github.com/stretchr/testify/assert"
+)
+
+func TestCheckUnadoptedRepositories_Add(t *testing.T) {
+	start := 10
+	end := 20
+	unadopted := &unadoptedRrepositories{
+		start: start,
+		end:   end,
+		index: 0,
+	}
+
+	total := 30
+	for i := 0; i < total; i++ {
+		unadopted.add("something")
+	}
+
+	assert.Equal(t, total, unadopted.index)
+	assert.Equal(t, end-start, len(unadopted.repositories))
+}
+
+func TestCheckUnadoptedRepositories(t *testing.T) {
+	assert.NoError(t, unittest.PrepareTestDatabase())
+	//
+	// Non existent user
+	//
+	unadopted := &unadoptedRrepositories{start: 0, end: 100}
+	err := checkUnadoptedRepositories("notauser", []string{"repo"}, unadopted)
+	assert.NoError(t, err)
+	assert.Equal(t, 0, len(unadopted.repositories))
+	//
+	// Unadopted repository is returned
+	// Existing (adopted) repository is not returned
+	//
+	userName := "user2"
+	repoName := "repo2"
+	unadoptedRepoName := "unadopted"
+	unadopted = &unadoptedRrepositories{start: 0, end: 100}
+	err = checkUnadoptedRepositories(userName, []string{repoName, unadoptedRepoName}, unadopted)
+	assert.NoError(t, err)
+	assert.Equal(t, []string{path.Join(userName, unadoptedRepoName)}, unadopted.repositories)
+	//
+	// Existing (adopted) repository is not returned
+	//
+	unadopted = &unadoptedRrepositories{start: 0, end: 100}
+	err = checkUnadoptedRepositories(userName, []string{repoName}, unadopted)
+	assert.NoError(t, err)
+	assert.Equal(t, 0, len(unadopted.repositories))
+	assert.Equal(t, 0, unadopted.index)
+}
+
+func TestListUnadoptedRepositories_ListOptions(t *testing.T) {
+	assert.NoError(t, unittest.PrepareTestDatabase())
+	username := "user2"
+	unadoptedList := []string{path.Join(username, "unadopted1"), path.Join(username, "unadopted2")}
+	for _, unadopted := range unadoptedList {
+		_ = os.Mkdir(path.Join(setting.RepoRootPath, unadopted+".git"), 0755)
+	}
+
+	opts := db.ListOptions{Page: 1, PageSize: 1}
+	repoNames, count, err := ListUnadoptedRepositories("", &opts)
+	assert.NoError(t, err)
+	assert.Equal(t, 2, count)
+	assert.Equal(t, unadoptedList[0], repoNames[0])
+
+	opts = db.ListOptions{Page: 2, PageSize: 1}
+	repoNames, count, err = ListUnadoptedRepositories("", &opts)
+	assert.NoError(t, err)
+	assert.Equal(t, 2, count)
+	assert.Equal(t, unadoptedList[1], repoNames[0])
+}