Fix bug

Author: lunny

services/automerge/automerge.go

@@ -5,12 +5,15 @@ package automerge
 
 import (
 	"context"
+	"errors"
 	"fmt"
 	"strconv"
 	"strings"
 
 	"code.gitea.io/gitea/models/db"
 	issues_model "code.gitea.io/gitea/models/issues"
+	"code.gitea.io/gitea/models/perm"
+	access_model "code.gitea.io/gitea/models/perm/access"
 	pull_model "code.gitea.io/gitea/models/pull"
 	repo_model "code.gitea.io/gitea/models/repo"
 	user_model "code.gitea.io/gitea/models/user"
@@ -281,7 +284,17 @@ func handlePullRequestAutoMerge(pullID int64, sha string) {
 	}
 
 	// We don't check doer's permission here because their permissions have been checked
-	// before ids were written to the auto_merge table
+	// before ids were stored to the auto_merge table
+	perm := access_model.Permission{AccessMode: perm.AccessModeWrite}
+
+	if err := pull_service.CheckPullMergeable(ctx, doer, &perm, pr, pull_service.MergeCheckTypeGeneral, false); err != nil {
+		if errors.Is(pull_service.ErrUserNotAllowedToMerge, err) {
+			log.Info("%-v was scheduled to automerge by an unauthorized user", pr)
+			return
+		}
+		log.Error("%-v CheckPullMergeable: %v", pr, err)
+		return
+	}
 
 	if err := pull_service.Merge(ctx, pr, doer, baseGitRepo, scheduledPRM.MergeStyle, "", scheduledPRM.Message, true); err != nil {
 		log.Error("pull_service.Merge: %v", err)