Fix some migration and repo name problems (#33986)

1. Ignore empty inputs in `UnmarshalHandleDoubleEncode`
2. Ignore non-existing `stateEvent.User` in gitlab migration
3. Enable `release` and `wiki` units when they are selected in migration
4. Sanitize repo name for migration and new repo

12 files changed, 123 insertions, 31 deletions

diff --git a/models/user/user_system.go b/models/user/user_system.go
index 6fbfd9e69e..e07274d291 100644
--- a/models/user/user_system.go
+++ b/models/user/user_system.go
@@ -10,8 +10,8 @@ import (
 )
 
 const (
-	GhostUserID   = -1
-	GhostUserName = "Ghost"
+	GhostUserID   int64 = -1
+	GhostUserName       = "Ghost"
 )
 
 // NewGhostUser creates and returns a fake user for someone has deleted their account.
@@ -36,9 +36,9 @@ func (u *User) IsGhost() bool {
 }
 
 const (
-	ActionsUserID    = -2
-	ActionsUserName  = "gitea-actions"
-	ActionsUserEmail = "teabot@gitea.io"
+	ActionsUserID    int64 = -2
+	ActionsUserName        = "gitea-actions"
+	ActionsUserEmail       = "teabot@gitea.io"
 )
 
 func IsGiteaActionsUserName(name string) bool {
diff --git a/modules/json/json.go b/modules/json/json.go
index 34568c75c6..acd4118573 100644
--- a/modules/json/json.go
+++ b/modules/json/json.go
@@ -145,6 +145,12 @@ func Valid(data []byte) bool {
 // UnmarshalHandleDoubleEncode - due to a bug in xorm (see https://gitea.com/xorm/xorm/pulls/1957) - it's
 // possible that a Blob may be double encoded or gain an unwanted prefix of 0xff 0xfe.
 func UnmarshalHandleDoubleEncode(bs []byte, v any) error {
+	if len(bs) == 0 {
+		// json.Unmarshal will report errors if input is empty (nil or zero-length)
+		// It seems that XORM ignores the nil but still passes zero-length string into this function
+		// To be consistent, we should treat all empty inputs as success
+		return nil
+	}
 	err := json.Unmarshal(bs, v)
 	if err != nil {
 		ok := true
diff --git a/modules/json/json_test.go b/modules/json/json_test.go
new file mode 100644
index 0000000000..ace7167913
--- /dev/null
+++ b/modules/json/json_test.go
@@ -0,0 +1,18 @@
+// Copyright 2025 The Gitea Authors. All rights reserved.
+// SPDX-License-Identifier: MIT
+
+package json
+
+import (
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+)
+
+func TestGiteaDBJSONUnmarshal(t *testing.T) {
+	var m map[any]any
+	err := UnmarshalHandleDoubleEncode(nil, &m)
+	assert.NoError(t, err)
+	err = UnmarshalHandleDoubleEncode([]byte(""), &m)
+	assert.NoError(t, err)
+}
diff --git a/services/auth/oauth2_test.go b/services/auth/oauth2_test.go
index 9edf18d58e..f003742a94 100644
--- a/services/auth/oauth2_test.go
+++ b/services/auth/oauth2_test.go
@@ -26,7 +26,7 @@ func TestUserIDFromToken(t *testing.T) {
 
 		o := OAuth2{}
 		uid := o.userIDFromToken(t.Context(), token, ds)
-		assert.Equal(t, int64(user_model.ActionsUserID), uid)
+		assert.Equal(t, user_model.ActionsUserID, uid)
 		assert.Equal(t, true, ds["IsActionsToken"])
 		assert.Equal(t, ds["ActionsTaskID"], int64(RunningTaskID))
 	})
diff --git a/services/doctor/fix16961_test.go b/services/doctor/fix16961_test.go
index 498ed9c8d5..d5eded1117 100644
--- a/services/doctor/fix16961_test.go
+++ b/services/doctor/fix16961_test.go
@@ -19,12 +19,6 @@ func Test_fixUnitConfig_16961(t *testing.T) {
 		wantErr   bool
 	}{
 		{
-			name:      "empty",
-			bs:        "",
-			wantFixed: true,
-			wantErr:   false,
-		},
-		{
 			name:      "normal: {}",
 			bs:        "{}",
 			wantFixed: false,
diff --git a/services/migrations/gitlab.go b/services/migrations/gitlab.go
index efc5b960cf..4bed8e2f6c 100644
--- a/services/migrations/gitlab.go
+++ b/services/migrations/gitlab.go
@@ -16,6 +16,7 @@ import (
 	"time"
 
 	issues_model "code.gitea.io/gitea/models/issues"
+	"code.gitea.io/gitea/models/user"
 	"code.gitea.io/gitea/modules/container"
 	"code.gitea.io/gitea/modules/log"
 	base "code.gitea.io/gitea/modules/migration"
@@ -535,11 +536,15 @@ func (g *GitlabDownloader) GetComments(ctx context.Context, commentable base.Com
 		}
 
 		for _, stateEvent := range stateEvents {
+			posterUserID, posterUsername := user.GhostUserID, user.GhostUserName
+			if stateEvent.User != nil {
+				posterUserID, posterUsername = int64(stateEvent.User.ID), stateEvent.User.Username
+			}
 			comment := &base.Comment{
 				IssueIndex: commentable.GetLocalIndex(),
 				Index:      int64(stateEvent.ID),
-				PosterID:   int64(stateEvent.User.ID),
-				PosterName: stateEvent.User.Username,
+				PosterID:   posterUserID,
+				PosterName: posterUsername,
 				Content:    "",
 				Created:    *stateEvent.CreatedAt,
 			}
diff --git a/services/repository/migrate.go b/services/repository/migrate.go
index 5b6feccb8d..9a5c6ffb0f 100644
--- a/services/repository/migrate.go
+++ b/services/repository/migrate.go
@@ -13,6 +13,7 @@ import (
 	"code.gitea.io/gitea/models/db"
 	"code.gitea.io/gitea/models/organization"
 	repo_model "code.gitea.io/gitea/models/repo"
+	unit_model "code.gitea.io/gitea/models/unit"
 	user_model "code.gitea.io/gitea/models/user"
 	"code.gitea.io/gitea/modules/git"
 	"code.gitea.io/gitea/modules/gitrepo"
@@ -246,6 +247,19 @@ func MigrateRepositoryGitData(ctx context.Context, u *user_model.User,
 		}
 	}
 
+	var enableRepoUnits []repo_model.RepoUnit
+	if opts.Releases && !unit_model.TypeReleases.UnitGlobalDisabled() {
+		enableRepoUnits = append(enableRepoUnits, repo_model.RepoUnit{RepoID: repo.ID, Type: unit_model.TypeReleases})
+	}
+	if opts.Wiki && !unit_model.TypeWiki.UnitGlobalDisabled() {
+		enableRepoUnits = append(enableRepoUnits, repo_model.RepoUnit{RepoID: repo.ID, Type: unit_model.TypeWiki})
+	}
+	if len(enableRepoUnits) > 0 {
+		err = UpdateRepositoryUnits(ctx, repo, enableRepoUnits, nil)
+		if err != nil {
+			return nil, err
+		}
+	}
 	return repo, committer.Commit()
 }
 
diff --git a/tests/integration/mirror_pull_test.go b/tests/integration/mirror_pull_test.go
index cf6faa7704..7ab8f72b4a 100644
--- a/tests/integration/mirror_pull_test.go
+++ b/tests/integration/mirror_pull_test.go
@@ -4,10 +4,12 @@
 package integration
 
 import (
+	"slices"
 	"testing"
 
 	"code.gitea.io/gitea/models/db"
 	repo_model "code.gitea.io/gitea/models/repo"
+	"code.gitea.io/gitea/models/unit"
 	"code.gitea.io/gitea/models/unittest"
 	user_model "code.gitea.io/gitea/models/user"
 	"code.gitea.io/gitea/modules/git"
@@ -19,11 +21,13 @@ import (
 	"code.gitea.io/gitea/tests"
 
 	"github.com/stretchr/testify/assert"
+	"github.com/stretchr/testify/require"
 )
 
 func TestMirrorPull(t *testing.T) {
 	defer tests.PrepareTestEnv(t)()
 
+	ctx := t.Context()
 	user := unittest.AssertExistsAndLoadBean(t, &user_model.User{ID: 2})
 	repo := unittest.AssertExistsAndLoadBean(t, &repo_model.Repository{ID: 1})
 	repoPath := repo_model.RepoPath(user.Name, repo.Name)
@@ -35,10 +39,10 @@ func TestMirrorPull(t *testing.T) {
 		Mirror:      true,
 		CloneAddr:   repoPath,
 		Wiki:        true,
-		Releases:    false,
+		Releases:    true,
 	}
 
-	mirrorRepo, err := repo_service.CreateRepositoryDirectly(db.DefaultContext, user, user, repo_service.CreateRepoOptions{
+	mirrorRepo, err := repo_service.CreateRepositoryDirectly(ctx, user, user, repo_service.CreateRepoOptions{
 		Name:        opts.RepoName,
 		Description: opts.Description,
 		IsPrivate:   opts.Private,
@@ -48,11 +52,15 @@ func TestMirrorPull(t *testing.T) {
 	assert.NoError(t, err)
 	assert.True(t, mirrorRepo.IsMirror, "expected pull-mirror repo to be marked as a mirror immediately after its creation")
 
-	ctx := t.Context()
-
-	mirror, err := repo_service.MigrateRepositoryGitData(ctx, user, mirrorRepo, opts, nil)
+	mirrorRepo, err = repo_service.MigrateRepositoryGitData(ctx, user, mirrorRepo, opts, nil)
 	assert.NoError(t, err)
 
+	// these units should have been enabled
+	mirrorRepo.Units = nil
+	require.NoError(t, mirrorRepo.LoadUnits(ctx))
+	assert.True(t, slices.ContainsFunc(mirrorRepo.Units, func(u *repo_model.RepoUnit) bool { return u.Type == unit.TypeReleases }))
+	assert.True(t, slices.ContainsFunc(mirrorRepo.Units, func(u *repo_model.RepoUnit) bool { return u.Type == unit.TypeWiki }))
+
 	gitRepo, err := gitrepo.OpenRepository(git.DefaultContext, repo)
 	assert.NoError(t, err)
 	defer gitRepo.Close()
@@ -60,10 +68,11 @@ func TestMirrorPull(t *testing.T) {
 	findOptions := repo_model.FindReleasesOptions{
 		IncludeDrafts: true,
 		IncludeTags:   true,
-		RepoID:        mirror.ID,
+		RepoID:        mirrorRepo.ID,
 	}
 	initCount, err := db.Count[repo_model.Release](db.DefaultContext, findOptions)
 	assert.NoError(t, err)
+	assert.Zero(t, initCount) // no sync yet, so even though there is a tag in source repo, the mirror's release table is still empty
 
 	assert.NoError(t, release_service.CreateRelease(gitRepo, &repo_model.Release{
 		RepoID:       repo.ID,
@@ -79,12 +88,15 @@ func TestMirrorPull(t *testing.T) {
 		IsTag:        true,
 	}, nil, ""))
 
-	_, err = repo_model.GetMirrorByRepoID(ctx, mirror.ID)
+	_, err = repo_model.GetMirrorByRepoID(ctx, mirrorRepo.ID)
 	assert.NoError(t, err)
 
-	ok := mirror_service.SyncPullMirror(ctx, mirror.ID)
+	ok := mirror_service.SyncPullMirror(ctx, mirrorRepo.ID)
 	assert.True(t, ok)
 
+	// actually there is a tag in the source repo, so after "sync", that tag will also come into the mirror
+	initCount++
+
 	count, err := db.Count[repo_model.Release](db.DefaultContext, findOptions)
 	assert.NoError(t, err)
 	assert.EqualValues(t, initCount+1, count)
@@ -93,7 +105,7 @@ func TestMirrorPull(t *testing.T) {
 	assert.NoError(t, err)
 	assert.NoError(t, release_service.DeleteReleaseByID(ctx, repo, release, user, true))
 
-	ok = mirror_service.SyncPullMirror(ctx, mirror.ID)
+	ok = mirror_service.SyncPullMirror(ctx, mirrorRepo.ID)
 	assert.True(t, ok)
 
 	count, err = db.Count[repo_model.Release](db.DefaultContext, findOptions)
diff --git a/web_src/js/features/repo-common.test.ts b/web_src/js/features/repo-common.test.ts
index 009dfc86b1..33a29ecb2c 100644
--- a/web_src/js/features/repo-common.test.ts
+++ b/web_src/js/features/repo-common.test.ts
@@ -1,7 +1,22 @@
-import {substituteRepoOpenWithUrl} from './repo-common.ts';
+import {sanitizeRepoName, substituteRepoOpenWithUrl} from './repo-common.ts';
 
 test('substituteRepoOpenWithUrl', () => {
   // For example: "x-github-client://openRepo/https://github.com/go-gitea/gitea"
   expect(substituteRepoOpenWithUrl('proto://a/{url}', 'https://gitea')).toEqual('proto://a/https://gitea');
   expect(substituteRepoOpenWithUrl('proto://a?link={url}', 'https://gitea')).toEqual('proto://a?link=https%3A%2F%2Fgitea');
 });
+
+test('sanitizeRepoName', () => {
+  expect(sanitizeRepoName(' a b ')).toEqual('a-b');
+  expect(sanitizeRepoName('a-b_c.git ')).toEqual('a-b_c');
+  expect(sanitizeRepoName('/x.git/')).toEqual('-x.git-');
+  expect(sanitizeRepoName('.profile')).toEqual('.profile');
+  expect(sanitizeRepoName('.profile.')).toEqual('.profile');
+  expect(sanitizeRepoName('.pro..file')).toEqual('.pro.file');
+
+  expect(sanitizeRepoName('foo.rss.atom.git.wiki')).toEqual('foo');
+
+  expect(sanitizeRepoName('.')).toEqual('');
+  expect(sanitizeRepoName('..')).toEqual('');
+  expect(sanitizeRepoName('-')).toEqual('');
+});
diff --git a/web_src/js/features/repo-common.ts b/web_src/js/features/repo-common.ts
index 4362a2c713..ebb6881c67 100644
--- a/web_src/js/features/repo-common.ts
+++ b/web_src/js/features/repo-common.ts
@@ -159,3 +159,19 @@ export async function updateIssuesMeta(url: string, action: string, issue_ids: s
     console.error(error);
   }
 }
+
+export function sanitizeRepoName(name: string): string {
+  name = name.trim().replace(/[^-.\w]/g, '-');
+  for (let lastName = ''; lastName !== name;) {
+    lastName = name;
+    name = name.replace(/\.+$/g, '');
+    name = name.replace(/\.{2,}/g, '.');
+    for (const ext of ['.git', '.wiki', '.rss', '.atom']) {
+      if (name.endsWith(ext)) {
+        name = name.substring(0, name.length - ext.length);
+      }
+    }
+  }
+  if (['.', '..', '-'].includes(name)) name = '';
+  return name;
+}
diff --git a/web_src/js/features/repo-migration.ts b/web_src/js/features/repo-migration.ts
index fb9c822f98..4914e47267 100644
--- a/web_src/js/features/repo-migration.ts
+++ b/web_src/js/features/repo-migration.ts
@@ -1,4 +1,5 @@
 import {hideElem, showElem, toggleElem} from '../utils/dom.ts';
+import {sanitizeRepoName} from './repo-common.ts';
 
 const service = document.querySelector<HTMLInputElement>('#service_type');
 const user = document.querySelector<HTMLInputElement>('#auth_username');
@@ -25,13 +26,19 @@ export function initRepoMigration() {
   });
   lfs?.addEventListener('change', setLFSSettingsVisibility);
 
-  const cloneAddr = document.querySelector<HTMLInputElement>('#clone_addr');
-  cloneAddr?.addEventListener('change', () => {
-    const repoName = document.querySelector<HTMLInputElement>('#repo_name');
-    if (cloneAddr.value && !repoName?.value) { // Only modify if repo_name input is blank
-      repoName.value = /^(.*\/)?((.+?)(\.git)?)$/.exec(cloneAddr.value)[3];
-    }
-  });
+  const elCloneAddr = document.querySelector<HTMLInputElement>('#clone_addr');
+  const elRepoName = document.querySelector<HTMLInputElement>('#repo_name');
+  if (elCloneAddr && elRepoName) {
+    let repoNameChanged = false;
+    elRepoName.addEventListener('input', () => {repoNameChanged = true});
+    elCloneAddr.addEventListener('input', () => {
+      if (repoNameChanged) return;
+      let repoNameFromUrl = elCloneAddr.value.split(/[?#]/)[0];
+      repoNameFromUrl = /^(.*\/)?((.+?)\/?)$/.exec(repoNameFromUrl)[3];
+      repoNameFromUrl = repoNameFromUrl.split(/[?#]/)[0];
+      elRepoName.value = sanitizeRepoName(repoNameFromUrl);
+    });
+  }
 }
 
 function checkAuth() {
diff --git a/web_src/js/features/repo-new.ts b/web_src/js/features/repo-new.ts
index f2c5eba62c..5128942465 100644
--- a/web_src/js/features/repo-new.ts
+++ b/web_src/js/features/repo-new.ts
@@ -1,6 +1,7 @@
 import {hideElem, showElem, toggleElem} from '../utils/dom.ts';
 import {htmlEscape} from 'escape-goat';
 import {fomanticQuery} from '../modules/fomantic/base.ts';
+import {sanitizeRepoName} from './repo-common.ts';
 
 const {appSubUrl} = window.config;
 
@@ -74,6 +75,10 @@ export function initRepoNew() {
     }
   };
   inputRepoName.addEventListener('input', updateUiRepoName);
+  inputRepoName.addEventListener('change', () => {
+    inputRepoName.value = sanitizeRepoName(inputRepoName.value);
+    updateUiRepoName();
+  });
   updateUiRepoName();
 
   initRepoNewTemplateSearch(form);