fix: PR merge (#39442)

* Revert the behavior introduced by #30805
* Now the PR status is still managed in Gitea's code where the operation
is triggerred but not in post-receive hook
* Fix #39254 and many more related bugs.
    * Fix #39124

```
// MarkAsMerged sets a pull request to merged and closes the corresponding issue
// To make sure the pull request is marked as merged correctly, the caller uses multiple-stage operations:
//  1. Create a temp repo from base, merge the head into the temp repo, and get the merged commit ID and timestamp,
//  2. The merged commit ID and related information are stored into pull request
//  3. Push the merged commit to the base repo
//  4. Call MarkAsMerged to mark the pull request as merged and do post-processing (notification, close issues, etc)
//
// If failure occurs in step 1/2/3: the pull request is still open, the base repo is not changed, the doer can start a new merge.
// If failure occurs in step 4: the pull request can be marked as merged by the merged commit ID stored in it later.
```

models/issues/pull.go

@@ -216,16 +216,10 @@ func (pr *PullRequest) OptionalHeadUserName(ctx context.Context) string {
 // LoadAttributes loads pull request attributes from database
 // Note: don't try to get Issue because will end up recursive querying.
 func (pr *PullRequest) LoadAttributes(ctx context.Context) (err error) {
-	if pr.HasMerged && pr.Merger == nil {
-		pr.Merger, err = user_model.GetUserByID(ctx, pr.MergerID)
-		if user_model.IsErrUserNotExist(err) {
-			pr.MergerID = user_model.GhostUserID
-			pr.Merger = user_model.NewGhostUser()
-		} else if err != nil {
-			return fmt.Errorf("getUserByID [%d]: %w", pr.MergerID, err)
-		}
+	if pr.Merger == nil && pr.MergerID != 0 {
+		pr.MergerID, pr.Merger, err = user_model.GetPossibleUserByID(ctx, pr.MergerID)
+		return err
 	}
-
 	return nil
 }
 

models/issues/pull_list.go

@@ -166,6 +166,14 @@ func GetPullRequestIDsByCheckStatus(ctx context.Context, status PullRequestStatu
 		Find(&prs)
 }
 
+func GetInterruptedPullRequestIDs(ctx context.Context) ([]int64, error) {
+	prs := make([]int64, 0, 10)
+	return prs, db.GetEngine(ctx).Table("pull_request").
+		Where("merged_commit_id <> '' AND has_merged = ? AND merged_unix >= ?", false, timeutil.TimeStampNow()-24*3600).
+		Cols("pull_request.id").
+		Find(&prs)
+}
+
 // PullRequests returns all pull requests for a base Repo by the given conditions
 func PullRequests(ctx context.Context, baseRepoID int64, opts *PullRequestsOptions) (PullRequestList, int64, error) {
 	if opts.Page <= 0 {

models/pull/automerge.go

@@ -23,6 +23,7 @@ type AutoMerge struct {
 	Message                string                `xorm:"LONGTEXT"`
 	DeleteBranchAfterMerge bool
 	CreatedUnix            timeutil.TimeStamp `xorm:"created"`
+	MergedCommitID         string             `xorm:"VARCHAR(64)"`
 }
 
 // TableName return database table name for xorm
@@ -86,15 +87,6 @@ func GetScheduledMergePullIDsSince(ctx context.Context, since timeutil.TimeStamp
 	return pullIDs, err
 }
 
-// DeleteScheduledAutoMerge delete a scheduled pull request
-func DeleteScheduledAutoMerge(ctx context.Context, pullID int64) error {
-	exist, scheduledPRM, err := GetScheduledMergeByPullID(ctx, pullID)
-	if err != nil {
-		return err
-	} else if !exist {
-		return db.ErrNotExist{Resource: "auto_merge", ID: pullID}
-	}
-
-	_, err = db.GetEngine(ctx).ID(scheduledPRM.ID).Delete(&AutoMerge{})
-	return err
+func DeleteScheduledAutoMerge(ctx context.Context, pullID int64) (int64, error) {
+	return db.GetEngine(ctx).Where("pull_id = ?", pullID).Delete(&AutoMerge{})
 }