检查异步方法的 Received() 调用

当我运行以下代码时：

[Test]
public async Task Can_Test_Update()
{
    var response = await _controller.UpdateAsync(Guid.NewGuid());
    response.Valid.Should().BeTrue();

    _commands.Received().UpdateAsync(
        Arg.Is<Something>(
            l => l.Status == Status.Updated)); 
}

如果我添加“await“ 之前的 ”_commands.Received().UpdateAsync”，它抛出一个空引用异常。我怎样才能阻止这种情况发生，或者是await不必要？

我找到了答案here https://gist.github.com/HEskandari/8235481.

Received.InOrder(async () =>
{
    await _Commands.UpdateAsync(Arg.Is<Lobby>(l => l.Status == Status.Updated));
});