Fix force push comments of pull request

services/pull/comment.go

@@ -6,6 +6,7 @@ package pull
 import (
 	"context"
 
+	"code.gitea.io/gitea/models/db"
 	issues_model "code.gitea.io/gitea/models/issues"
 	repo_model "code.gitea.io/gitea/models/repo"
 	user_model "code.gitea.io/gitea/models/user"
@@ -61,27 +62,51 @@ func CreatePushPullComment(ctx context.Context, pusher *user_model.User, pr *iss
 	}
 
 	var data issues_model.PushActionContent
-	if opts.IsForcePush {
-		data.CommitIDs = []string{oldCommitID, newCommitID}
-		data.IsForcePush = true
-	} else {
-		data.CommitIDs, err = getCommitIDsFromRepo(ctx, pr.BaseRepo, oldCommitID, newCommitID, pr.BaseBranch)
-		if err != nil {
-			return nil, err
-		}
-		// It maybe an empty pull request. Only non-empty pull request need to create push comment
-		if len(data.CommitIDs) == 0 {
-			return nil, nil //nolint:nilnil // return nil because no comment needs to be created
-		}
-	}
-
-	dataJSON, err := json.Marshal(data)
+	data.CommitIDs, err = getCommitIDsFromRepo(ctx, pr.BaseRepo, oldCommitID, newCommitID, pr.BaseBranch)
 	if err != nil {
 		return nil, err
 	}
+	// It maybe an empty pull request. Only non-empty pull request need to create push comment
+	if len(data.CommitIDs) == 0 && !isForcePush {
+		return nil, nil //nolint:nilnil // return nil because no comment needs to be created
+	}
 
-	opts.Content = string(dataJSON)
-	comment, err = issues_model.CreateComment(ctx, opts)
+	return db.WithTx2(ctx, func(ctx context.Context) (*issues_model.Comment, error) {
+		if isForcePush {
+			if _, err := db.GetEngine(ctx).Where("issue_id = ?", pr.IssueID).
+				And("type = ?", issues_model.CommentTypePullRequestPush).
+				NoAutoCondition().
+				Delete(new(issues_model.Comment)); err != nil {
+				return nil, err
+			}
+		}
 
-	return comment, err
+		if len(data.CommitIDs) > 0 {
+			dataJSON, err := json.Marshal(data)
+			if err != nil {
+				return nil, err
+			}
+			opts.Content = string(dataJSON)
+			comment, err = issues_model.CreateComment(ctx, opts)
+			if err != nil {
+				return nil, err
+			}
+		}
+
+		if opts.IsForcePush { // if it's a force push, we needs to add a force push comment
+			data.CommitIDs = []string{oldCommitID, newCommitID}
+			data.IsForcePush = true
+			dataJSON, err := json.Marshal(data)
+			if err != nil {
+				return nil, err
+			}
+			opts.Content = string(dataJSON)
+			comment, err = issues_model.CreateComment(ctx, opts)
+			if err != nil {
+				return nil, err
+			}
+		}
+
+		return comment, err
+	})
 }

services/pull/comment_test.go

@@ -0,0 +1,94 @@
+// Copyright 2025 The Gitea Authors. All rights reserved.
+// SPDX-License-Identifier: MIT
+
+package pull
+
+import (
+	"testing"
+
+	issues_model "code.gitea.io/gitea/models/issues"
+	"code.gitea.io/gitea/models/unittest"
+	user_model "code.gitea.io/gitea/models/user"
+	"code.gitea.io/gitea/modules/gitrepo"
+	"code.gitea.io/gitea/modules/json"
+
+	"github.com/stretchr/testify/assert"
+)
+
+func TestCreatePushPullCommentForcePushDeletesOldComments(t *testing.T) {
+	assert.NoError(t, unittest.PrepareTestDatabase())
+
+	pr := unittest.AssertExistsAndLoadBean(t, &issues_model.PullRequest{ID: 2})
+	assert.NoError(t, pr.LoadIssue(t.Context()))
+	assert.NoError(t, pr.LoadBaseRepo(t.Context()))
+
+	pusher := unittest.AssertExistsAndLoadBean(t, &user_model.User{ID: 1})
+
+	_, err := issues_model.CreateComment(t.Context(), &issues_model.CreateCommentOptions{
+		Type:    issues_model.CommentTypePullRequestPush,
+		Doer:    pusher,
+		Repo:    pr.BaseRepo,
+		Issue:   pr.Issue,
+		Content: "{}",
+	})
+	assert.NoError(t, err)
+	_, err = issues_model.CreateComment(t.Context(), &issues_model.CreateCommentOptions{
+		Type:    issues_model.CommentTypePullRequestPush,
+		Doer:    pusher,
+		Repo:    pr.BaseRepo,
+		Issue:   pr.Issue,
+		Content: "{}",
+	})
+	assert.NoError(t, err)
+
+	comments, err := issues_model.FindComments(t.Context(), &issues_model.FindCommentsOptions{
+		IssueID: pr.IssueID,
+		Type:    issues_model.CommentTypePullRequestPush,
+	})
+	assert.NoError(t, err)
+	assert.Len(t, comments, 2)
+
+	gitRepo, err := gitrepo.OpenRepository(t.Context(), pr.BaseRepo)
+	assert.NoError(t, err)
+	defer gitRepo.Close()
+
+	headCommit, err := gitRepo.GetBranchCommit(pr.BaseBranch)
+	assert.NoError(t, err)
+	oldCommit := headCommit
+	if headCommit.ParentCount() > 0 {
+		parentCommit, err := headCommit.Parent(0)
+		assert.NoError(t, err)
+		oldCommit = parentCommit
+	}
+
+	comment, err := CreatePushPullComment(t.Context(), pusher, pr, oldCommit.ID.String(), headCommit.ID.String(), true)
+	assert.NoError(t, err)
+	assert.NotNil(t, comment)
+	var createdData issues_model.PushActionContent
+	assert.NoError(t, json.Unmarshal([]byte(comment.Content), &createdData))
+	assert.True(t, createdData.IsForcePush)
+
+	commits, err := gitRepo.CommitsBetweenNotBase(headCommit, oldCommit, pr.BaseBranch)
+	assert.NoError(t, err)
+	expectedCount := 1
+	if len(commits) > 0 {
+		expectedCount = 2
+	}
+
+	comments, err = issues_model.FindComments(t.Context(), &issues_model.FindCommentsOptions{
+		IssueID: pr.IssueID,
+		Type:    issues_model.CommentTypePullRequestPush,
+	})
+	assert.NoError(t, err)
+	assert.Len(t, comments, expectedCount)
+
+	forcePushCount := 0
+	for _, comment := range comments {
+		var pushData issues_model.PushActionContent
+		assert.NoError(t, json.Unmarshal([]byte(comment.Content), &pushData))
+		if pushData.IsForcePush {
+			forcePushCount++
+		}
+	}
+	assert.Equal(t, 1, forcePushCount)
+}