Start automerge check again after the conflict check and the schedule (#34989)

Fix #34988

Co-authored-by: posativ

services/automergequeue/automergequeue.go

@@ -0,0 +1,49 @@
+// Copyright 2025 The Gitea Authors. All rights reserved.
+// SPDX-License-Identifier: MIT
+
+package automergequeue
+
+import (
+	"context"
+	"fmt"
+
+	issues_model "code.gitea.io/gitea/models/issues"
+	"code.gitea.io/gitea/modules/gitrepo"
+	"code.gitea.io/gitea/modules/log"
+	"code.gitea.io/gitea/modules/queue"
+)
+
+var AutoMergeQueue *queue.WorkerPoolQueue[string]
+
+var AddToQueue = func(pr *issues_model.PullRequest, sha string) {
+	log.Trace("Adding pullID: %d to the pull requests patch checking queue with sha %s", pr.ID, sha)
+	if err := AutoMergeQueue.Push(fmt.Sprintf("%d_%s", pr.ID, sha)); err != nil {
+		log.Error("Error adding pullID: %d to the pull requests patch checking queue %v", pr.ID, err)
+	}
+}
+
+// StartPRCheckAndAutoMerge start an automerge check and auto merge task for a pull request
+func StartPRCheckAndAutoMerge(ctx context.Context, pull *issues_model.PullRequest) {
+	if pull == nil || pull.HasMerged || !pull.CanAutoMerge() {
+		return
+	}
+
+	if err := pull.LoadBaseRepo(ctx); err != nil {
+		log.Error("LoadBaseRepo: %v", err)
+		return
+	}
+
+	gitRepo, err := gitrepo.OpenRepository(ctx, pull.BaseRepo)
+	if err != nil {
+		log.Error("OpenRepository: %v", err)
+		return
+	}
+	defer gitRepo.Close()
+	commitID, err := gitRepo.GetRefCommitID(pull.GetGitRefName())
+	if err != nil {
+		log.Error("GetRefCommitID: %v", err)
+		return
+	}
+
+	AddToQueue(pull, commitID)
+}