def METHOD_NAME(tracer):
    """
    Ensure a simple trace doesn't leak span objects.
    """
    wd = WeakValueDictionary()
    with trace(wd, tracer, "span1"):
        with trace(wd, tracer, "span2"):
            pass
    # Spans are serialized and unreferenced when traces are finished
    # so gc-ing right away should delete all span objects.
    gc.collect()
    assert len(wd) == 0