Fix bug when pushing to a pull request which enabled dismiss approval automatically (#25882) (#26158)

Fix #25858
Backport #25882 

The option `dissmiss stale approvals` was listed on protected branch but
never implemented. This PR fixes that.

<img width="1006" alt="图片"

src="https://github.com/go-gitea/gitea/assets/81045/60bfa968-4db7-4c24-b8be-2e5978f91bb9">

<img width="1021" alt="图片"

src="https://github.com/go-gitea/gitea/assets/81045/8dabc14d-2dfe-40c2-94ed-24fcbf6e0e8f">

2 files changed, 63 insertions, 9 deletions

diff --git a/services/pull/pull.go b/services/pull/pull.go
index 8f2befa8ff..55c400947b 100644
--- a/services/pull/pull.go
+++ b/services/pull/pull.go
@@ -302,6 +302,17 @@ func AddTestPullRequestTask(doer *user_model.User, repoID int64, branch string,
 							if err := issues_model.MarkReviewsAsStale(pr.IssueID); err != nil {
 								log.Error("MarkReviewsAsStale: %v", err)
 							}
+
+							// dismiss all approval reviews if protected branch rule item enabled.
+							pb, err := git_model.GetFirstMatchProtectedBranchRule(ctx, pr.BaseRepoID, pr.BaseBranch)
+							if err != nil {
+								log.Error("GetFirstMatchProtectedBranchRule: %v", err)
+							}
+							if pb != nil && pb.DismissStaleApprovals {
+								if err := DismissApprovalReviews(ctx, doer, pr); err != nil {
+									log.Error("DismissApprovalReviews: %v", err)
+								}
+							}
 						}
 						if err := issues_model.MarkReviewsAsNotStale(pr.IssueID, newCommitID); err != nil {
 							log.Error("MarkReviewsAsNotStale: %v", err)
diff --git a/services/pull/review.go b/services/pull/review.go
index 6feffe4ec4..6b8373c089 100644
--- a/services/pull/review.go
+++ b/services/pull/review.go
@@ -316,6 +316,52 @@ func SubmitReview(ctx context.Context, doer *user_model.User, gitRepo *git.Repos
 	return review, comm, nil
 }
 
+// DismissApprovalReviews dismiss all approval reviews because of new commits
+func DismissApprovalReviews(ctx context.Context, doer *user_model.User, pull *issues_model.PullRequest) error {
+	reviews, err := issues_model.FindReviews(ctx, issues_model.FindReviewOptions{
+		ListOptions: db.ListOptions{
+			ListAll: true,
+		},
+		IssueID:   pull.IssueID,
+		Type:      issues_model.ReviewTypeApprove,
+		Dismissed: util.OptionalBoolFalse,
+	})
+	if err != nil {
+		return err
+	}
+
+	if err := reviews.LoadIssues(ctx); err != nil {
+		return err
+	}
+
+	return db.WithTx(ctx, func(subCtx context.Context) error {
+		for _, review := range reviews {
+			if err := issues_model.DismissReview(subCtx, review, true); err != nil {
+				return err
+			}
+
+			comment, err := issue_service.CreateComment(ctx, &issues_model.CreateCommentOptions{
+				Doer:     doer,
+				Content:  "New commits pushed, approval review dismissed automatically according to repository settings",
+				Type:     issues_model.CommentTypeDismissReview,
+				ReviewID: review.ID,
+				Issue:    review.Issue,
+				Repo:     review.Issue.Repo,
+			})
+			if err != nil {
+				return err
+			}
+
+			comment.Review = review
+			comment.Poster = doer
+			comment.Issue = review.Issue
+
+			notification.NotifyPullReviewDismiss(ctx, doer, review, comment)
+		}
+		return nil
+	})
+}
+
 // DismissReview dismissing stale review by repo admin
 func DismissReview(ctx context.Context, reviewID, repoID int64, message string, doer *user_model.User, isDismiss, dismissPriors bool) (comment *issues_model.Comment, err error) {
 	review, err := issues_model.GetReviewByID(ctx, reviewID)
@@ -337,12 +383,12 @@ func DismissReview(ctx context.Context, reviewID, repoID int64, message string,
 		return nil, fmt.Errorf("reviews's repository is not the same as the one we expect")
 	}
 
-	if err = issues_model.DismissReview(review, isDismiss); err != nil {
-		return
+	if err := issues_model.DismissReview(ctx, review, isDismiss); err != nil {
+		return nil, err
 	}
 
 	if dismissPriors {
-		reviews, err := issues_model.GetReviews(ctx, &issues_model.GetReviewOptions{
+		reviews, err := issues_model.FindReviews(ctx, issues_model.FindReviewOptions{
 			IssueID:    review.IssueID,
 			ReviewerID: review.ReviewerID,
 			Dismissed:  util.OptionalBoolFalse,
@@ -351,7 +397,7 @@ func DismissReview(ctx context.Context, reviewID, repoID int64, message string,
 			return nil, err
 		}
 		for _, oldReview := range reviews {
-			if err = issues_model.DismissReview(oldReview, true); err != nil {
+			if err = issues_model.DismissReview(ctx, oldReview, true); err != nil {
 				return nil, err
 			}
 		}
@@ -361,11 +407,8 @@ func DismissReview(ctx context.Context, reviewID, repoID int64, message string,
 		return nil, nil
 	}
 
-	if err = review.Issue.LoadPullRequest(ctx); err != nil {
-		return
-	}
-	if err = review.Issue.LoadAttributes(ctx); err != nil {
-		return
+	if err := review.Issue.LoadAttributes(ctx); err != nil {
+		return nil, err
 	}
 
 	comment, err = issue_service.CreateComment(ctx, &issues_model.CreateCommentOptions{