In WT-11820, the following assertion was added in test/suite/wtbackup.py:

    def take_full_backup(self, backup_dir, backup_cur=None):
        assert os.path.exists(backup_dir), f"The directory '{backup_dir}' does not exist"

This ensures the backup dir has been created before creating a full backup. If we don't create it, the function simply copies the files and renames each of them to the folder's name that was supposed to be the folder for the backup.

Example of failing task.

This ticket should either add this assert or silently create the folder if it does not exist yet and fix the impacted tests.