Don't manipulate input params in email notification (#16011) (#16033)

Backport #16011

Author: jpraet

modules/notification/mail/mail.go

@@ -54,7 +54,6 @@ func (m *mailNotifier) NotifyNewIssue(issue *models.Issue, mentions []*models.Us
 
 func (m *mailNotifier) NotifyIssueChangeStatus(doer *models.User, issue *models.Issue, actionComment *models.Comment, isClosed bool) {
 	var actionType models.ActionType
-	issue.Content = ""
 	if issue.IsPull {
 		if isClosed {
 			actionType = models.ActionClosePullRequest
@@ -120,7 +119,6 @@ func (m *mailNotifier) NotifyMergePullRequest(pr *models.PullRequest, doer *mode
 		log.Error("pr.LoadIssue: %v", err)
 		return
 	}
-	pr.Issue.Content = ""
 	if err := mailer.MailParticipants(pr.Issue, doer, models.ActionMergePullRequest, nil); err != nil {
 		log.Error("MailParticipants: %v", err)
 	}
@@ -147,7 +145,6 @@ func (m *mailNotifier) NotifyPullRequestPushCommits(doer *models.User, pr *model
 	if err := comment.LoadPushCommits(); err != nil {
 		log.Error("comment.LoadPushCommits: %v", err)
 	}
-	comment.Content = ""
 
 	m.NotifyCreateIssueComment(doer, comment.Issue.Repo, comment.Issue, comment, nil)
 }

services/mailer/mail_comment.go

@@ -20,12 +20,16 @@ func mailParticipantsComment(c *models.Comment, opType models.ActionType, issue
 	for i, u := range mentions {
 		mentionedIDs[i] = u.ID
 	}
+	content := c.Content
+	if c.Type == models.CommentTypePullPush {
+		content = ""
+	}
 	if err = mailIssueCommentToParticipants(
 		&mailCommentContext{
 			Issue:      issue,
 			Doer:       c.Poster,
 			ActionType: opType,
-			Content:    c.Content,
+			Content:    content,
 			Comment:    c,
 		}, mentionedIDs); err != nil {
 		log.Error("mailIssueCommentToParticipants: %v", err)

services/mailer/mail_issue.go

@@ -158,12 +158,18 @@ func mailParticipants(issue *models.Issue, doer *models.User, opType models.Acti
 	for i, u := range mentions {
 		mentionedIDs[i] = u.ID
 	}
+	content := issue.Content
+	if opType == models.ActionCloseIssue || opType == models.ActionClosePullRequest ||
+		opType == models.ActionReopenIssue || opType == models.ActionReopenPullRequest ||
+		opType == models.ActionMergePullRequest {
+		content = ""
+	}
 	if err = mailIssueCommentToParticipants(
 		&mailCommentContext{
 			Issue:      issue,
 			Doer:       doer,
 			ActionType: opType,
-			Content:    issue.Content,
+			Content:    content,
 			Comment:    nil,
 		}, mentionedIDs); err != nil {
 		log.Error("mailIssueCommentToParticipants: %v", err)