1 files changed, 5 insertions, 0 deletions

diff --git a/models/issues/milestone.go b/models/issues/milestone.go
index 1021938b20..3ccade7411 100644
--- a/models/issues/milestone.go
+++ b/models/issues/milestone.go
@@ -15,6 +15,7 @@ import (
 	"code.gitea.io/gitea/modules/setting"
 	api "code.gitea.io/gitea/modules/structs"
 	"code.gitea.io/gitea/modules/timeutil"
+	"code.gitea.io/gitea/modules/util"
 
 	"xorm.io/builder"
 )
@@ -39,6 +40,10 @@ func (err ErrMilestoneNotExist) Error() string {
 	return fmt.Sprintf("milestone does not exist [id: %d, repo_id: %d]", err.ID, err.RepoID)
 }
 
+func (err ErrMilestoneNotExist) Unwrap() error {
+	return util.ErrNotExist
+}
+
 // Milestone represents a milestone of repository.
 type Milestone struct {
 	ID              int64                  `xorm:"pk autoincr"`