From 0af8cacd4d513e75fa0c58890f7d5014cf204c08 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?=E2=98=99=E2=97=A6=20The=20Tablet=20=E2=9D=80=20GamerGirla?=
 =?UTF-8?q?ndCo=20=E2=97=A6=E2=9D=A7?= <i.am.the.tablet@proton.me>
Date: Wed, 6 May 2026 21:11:01 -0400
Subject: [PATCH] refactor: add `permission denied` error type to group model
 package

---
 models/group/errors.go  | 18 ++++++++++++++++++
 services/group/group.go |  5 ++++-
 2 files changed, 22 insertions(+), 1 deletion(-)

diff --git a/models/group/errors.go b/models/group/errors.go
index 812fc6ddc9..52aafbf655 100644
--- a/models/group/errors.go
+++ b/models/group/errors.go
@@ -42,3 +42,21 @@ func IsErrGroupTooDeep(err error) bool {
 func (err ErrGroupTooDeep) Error() string {
 	return fmt.Sprintf("group has reached or exceeded the subgroup nesting limit [id: %d]", err.ID)
 }
+
+type ErrUserDoesNotHaveAccessToGroup struct {
+	UserID, GroupID int64
+}
+
+func (e ErrUserDoesNotHaveAccessToGroup) Error() string {
+	return fmt.Sprintf("user %d does not have access to group %d", e.UserID, e.GroupID)
+}
+
+func (e ErrUserDoesNotHaveAccessToGroup) Unwrap() error {
+	return util.ErrPermissionDenied
+}
+
+func IsErrUserDoesNotHaveAccessToGroup(err error) bool {
+	var eNoAccess ErrUserDoesNotHaveAccessToGroup
+	ok := errors.As(err, &eNoAccess)
+	return ok
+}
diff --git a/services/group/group.go b/services/group/group.go
index d09077cbbf..ad48baaeb7 100644
--- a/services/group/group.go
+++ b/services/group/group.go
@@ -98,7 +98,10 @@ func MoveGroupItem(ctx context.Context, opts MoveGroupOptions, doer *user_model.
 			return err
 		}
 		if !canAccessNewParent {
-			return errors.New("cannot access new parent group")
+			return group_model.ErrUserDoesNotHaveAccessToGroup{
+				GroupID: opts.NewParent,
+				UserID:  doer.ID,
+			}
 		}
 
 		err = parentGroup.LoadSubgroups(ctx, false)