def insert_source_info(result):
    """Add info about source of test result if available."""
    comment = result.get('comment')
    if comment:
        return
    source = result.get('source')
    job_name = result.get('job_name')
    run = result.get('run')
    source_list = [source, job_name, run]
    if not all(source_list):
        return
    source_note = '/'.join(source_list)
    source_note = 'Source: {}'.format(source_note)
    result['comment'] = source_note
