Merge pull request #5635 from techAPJ/invite-muted

FIX: do not allow invite notifications from muted user/topic

app/models/topic.rb

@@ -791,6 +791,8 @@ SQL
       raise UserExists.new(I18n.t("topic_invite.user_exists"))
     end
 
+    return true if target_user && invite_existing_muted?(target_user, invited_by)
+
     if target_user && private_message? && topic_allowed_users.create!(user_id: target_user.id)
       add_small_action(invited_by, "invited_user", target_user.username)
 
@@ -835,6 +837,26 @@ SQL
     Invite.invite_by_email(email, invited_by, self, group_ids, custom_message)
   end
 
+  def invite_existing_muted?(target_user, invited_by)
+    if invited_by.id &&
+       MutedUser.where(user_id: target_user.id, muted_user_id: invited_by.id)
+           .joins(:muted_user)
+           .where('NOT admin AND NOT moderator')
+           .exists?
+      return true
+    end
+
+    if TopicUser.where(
+         topic: self,
+         user: target_user,
+         notification_level: TopicUser.notification_levels[:muted]
+        ).exists?
+      return true
+    end
+
+    false
+  end
+
   def email_already_exists_for?(invite)
     invite.email_already_exists && private_message?
   end