我怎么能写一个单元测试，以确定是否一个对象被垃圾收集？ [英] How can I write a unit test to determine whether an object can be garbage collected?

问题描述

关于<一个href="http://stackoverflow.com/questions/578593/castle-windsor-will-my-transient-component-be-garbage-collected">my previous问题，我需要检查的部件将由温莎城堡被实例化，是否可以被垃圾收集后，我的code。使用它已经完成。我试图从previous问题的答案的建议，但它似乎并没有按预期，至少在我的code。所以我想编写一个单元测试，测试是否特定对象实例可以后我的一些code已经运行垃圾进行回收。

In relation to my previous question, I need to check whether a component that will be instantiated by Castle Windsor, can be garbage collected after my code has finished using it. I have tried the suggestion in the answers from the previous question, but it does not seem to work as expected, at least for my code. So I would like to write a unit test that tests whether a specific object instance can be garbage collected after some of my code has run.

这有可能做一个可靠的方法是什么？

Is that possible to do in a reliable way ?

修改

我现在有一个基于保罗Stovell的回答下面的测试，成功：

I currently have the following test based on Paul Stovell's answer, which succeeds:

     [TestMethod]
    public void ReleaseTest()
    {
        WindsorContainer container = new WindsorContainer();
        container.Kernel.ReleasePolicy = new NoTrackingReleasePolicy();
        container.AddComponentWithLifestyle<ReleaseTester>(LifestyleType.Transient);
        Assert.AreEqual(0, ReleaseTester.refCount);
        var weakRef = new WeakReference(container.Resolve<ReleaseTester>());
        Assert.AreEqual(1, ReleaseTester.refCount);
        GC.Collect();
        GC.WaitForPendingFinalizers();
        Assert.AreEqual(0, ReleaseTester.refCount, "Component not released");
    }

    private class ReleaseTester
    {
        public static int refCount = 0;

        public ReleaseTester()
        {
            refCount++;
        }

        ~ReleaseTester()
        {
            refCount--;
        }
    }

我说得对假设的基础上，上面的测试，我可以断定，使用NoTrackingReleasePolicy温莎时，不会造成内存泄露？

Am I right assuming that, based on the test above, I can conclude that Windsor will not leak memory when using the NoTrackingReleasePolicy ?

推荐答案

这就是我通常做的：

[Test]
public void MyTest() 
{
    WeakReference reference;
    new Action(() => 
    {
        var service = new Service();
        // Do things with service that might cause a memory leak...

        reference = new WeakReference(service, true);
    })();

    // Service should have gone out of scope about now, 
    // so the garbage collector can clean it up
    GC.Collect();
    GC.WaitForPendingFinalizers();

    Assert.IsNull(reference.Target);
}

注：有非常，非常几次，你应该在生产应用程序调用GC.Collect（）。但是，测试是否泄漏是地方适当的一个例子。

NB: There are very, very few times where you should call GC.Collect() in a production application. But testing for leaks is one example of where it's appropriate.

这篇关于我怎么能写一个单元测试，以确定是否一个对象被垃圾收集？的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！