Fix commit range paging (#32944) (#32962)

Backport #32944 by wxiaoguang

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

modules/git/repo_commit.go

@@ -216,8 +216,6 @@ type CommitsByFileAndRangeOptions struct {
 
 // CommitsByFileAndRange return the commits according revision file and the page
 func (repo *Repository) CommitsByFileAndRange(opts CommitsByFileAndRangeOptions) ([]*Commit, error) {
-	skip := (opts.Page - 1) * setting.Git.CommitsRangeSize
-
 	stdoutReader, stdoutWriter := io.Pipe()
 	defer func() {
 		_ = stdoutReader.Close()
@@ -226,8 +224,8 @@ func (repo *Repository) CommitsByFileAndRange(opts CommitsByFileAndRangeOptions)
 	go func() {
 		stderr := strings.Builder{}
 		gitCmd := NewCommand(repo.Ctx, "rev-list").
-			AddOptionFormat("--max-count=%d", setting.Git.CommitsRangeSize*opts.Page).
+			AddOptionFormat("--max-count=%d", setting.Git.CommitsRangeSize).
-			AddOptionFormat("--skip=%d", skip)
+			AddOptionFormat("--skip=%d", (opts.Page-1)*setting.Git.CommitsRangeSize)
 		gitCmd.AddDynamicArguments(opts.Revision)
 
 		if opts.Not != "" {

modules/git/repo_commit_test.go

@@ -8,7 +8,11 @@ import (
 	"path/filepath"
 	"testing"
 
+	"code.gitea.io/gitea/modules/setting"
+	"code.gitea.io/gitea/modules/test"
+
 	"github.com/stretchr/testify/assert"
+	"github.com/stretchr/testify/require"
 )
 
 func TestRepository_GetCommitBranches(t *testing.T) {
@@ -126,3 +130,21 @@ func TestGetRefCommitID(t *testing.T) {
 		}
 	}
 }
+
+func TestCommitsByFileAndRange(t *testing.T) {
+	defer test.MockVariableValue(&setting.Git.CommitsRangeSize, 2)()
+
+	bareRepo1Path := filepath.Join(testReposDir, "repo1_bare")
+	bareRepo1, err := openRepositoryWithDefaultContext(bareRepo1Path)
+	require.NoError(t, err)
+	defer bareRepo1.Close()
+
+	// "foo" has 3 commits in "master" branch
+	commits, err := bareRepo1.CommitsByFileAndRange(CommitsByFileAndRangeOptions{Revision: "master", File: "foo", Page: 1})
+	require.NoError(t, err)
+	assert.Len(t, commits, 2)
+
+	commits, err = bareRepo1.CommitsByFileAndRange(CommitsByFileAndRangeOptions{Revision: "master", File: "foo", Page: 2})
+	require.NoError(t, err)
+	assert.Len(t, commits, 1)
+}