NUnit2.0详细使用方法 （二）
TestFixtureSetUp/TestFixtureTearDown ?? 有时,一组测试需要的资源太昂贵.例如,数据库连接可能是一个关键资源,在一个test fixture的每个测试中,打开/关闭数据库连接可能非常慢.这就是我在开始提到的问题.如何解决?NUnit有一对类似于前面讨论的SetUp/TearDown的属性: TestFixtureSetUp/TestFixtureTearDown.正如他们名字表明的一样,这些属性用来标记为整个test fixture初始化/释放资源方法一次的方法. ?? 例如,如果你想为所有test fixture的测试共享相同的数据库连接对象,我们可以写一个打开数据库连接的方法,标记为TestFixtureSetUp属性,编写另外一个关闭数据库连接的方法,标记为TestFixtureTearDown属性.这里是描述这个的例子.

?1using?NUnit.Framework;?2?3[TestFixture]?4public?class?DatabaseFixture?5{?6???[TestFixtureSetUp]?7???public?void?OpenConnection()?8???{?9??????//open?the?connection?to?the?database10???}11?12???[TestFixtureTearDown]13???public?void?CloseConnection()14???{15??????//close?the?connection?to?the?database16???}17???18???[SetUp]19???public?void?CreateDatabaseObjects()20???{21??????//insert?the?records?into?the?database?table22???}23?24???[TearDown]25???public?void?DeleteDatabaseObjects()26???{27??????//remove?the?inserted?records?from?the?database?table28???}29?30???[Test]31???public?void?ReadOneObject()32???{33??????//load?one?record?using?the?open?database?connection34???}35?36???[Test]37???public?void?ReadManyObjects()38???{39??????//load?many?records?using?the?open?database?connection40???}41}4243

Test Suite?? Test Suite是test case或其他test suite的集合. 合成(Composite),模式描述了test case和test suite之间的关系. ?参考来自NUnit的关于Suite的代码 Suite Attribute ?1namespace?NUnit.Tests
?2{
?3using?System;
?4??using?NUnit.Framework;
?5?
?6
?7
?8??public?class?AllTests
?9??{
10????[Suite]
11????public?static?TestSuite?Suite
12????{
13??????get
14??????{
15????????TestSuite?suite?=?new?TestSuite("All?Tests");
16????????suite.Add(new?OneTestCase());
17????????suite.Add(new?Assemblies.AssemblyTests());
18????????suite.Add(new?AssertionTest());
19????????return?suite;
20??????}
21????}
22??}
23}?
24 Category属性 ?对于测试来说，你有的时候需要将之分类，此属性正好就是用来解决这个问题的。 ?你可以选择你需要运行的测试类目录，也可以选择除了这些目录之外的测试都可以运行。在命令行环境里 /include 和/exclude来实现。在GUI环境下，就更简单了，选择左边工作域里的Catagories Tab，选择Add和Remove既可以了。 在上面的例子上做了一些改善，代码如下：

?1using?System;??2using?NUnit.Framework;??3???4namespace?NUnitQuickStart??5{??6????????????[TestFixture]??7????????????public?class?NumersFixture??8????????????{??9????????????????????????private?int?a;?10????????????????????????private?int?b;?11????????????????????????[SetUp]?12????????????????????????public??void?InitializeOperands()?13????????????????????????{?14????????????????????????????????????a?=?1;?15????????????????????????????????????b?=?2;?16????????????????????????}?17??18????????????????????????[Test]?19????????????????????????[Category("Numbers")]?20????????????????????????public?void?AddTwoNumbers()?21????????????????????????{?22????????????????????????????????????int?sum=a+b;?23????????????????????????????????????Assert.AreEqual(sum,3);?24????????????????????????}?25????????????????????????26????????????????????????[Test]?27????????????????[Category("Exception")]?28????????????????????????[ExpectedException(typeof(DivideByZeroException))]?29????????????????????????public?void?DivideByZero()?30????????????????????????{?31????????????????????????????????????int?zero?=?0;?32????????????????????????????????????int?infinity?=?a/zero;?33????????????????????????????????????Assert.Fail("Should?have?gotten?an?exception");?34????????????????????????}?35????????????????????????[Test]?36????????????????????????[Ignore("Multiplication?is?ignored")]?37????????????????????????[Category("Numbers")]?38????????????????????????public?void?MultiplyTwoNumbers()?39????????????????????????{?40????????????????????????????????????int?product?=?a?*?b;?41????????????????????????????????????Assert.AreEqual(2,?product);?42????????????????????????}?43??44???????????????}?45??????? NUnit-GUI界面如图5-2：

图5-2:使用Catagories属性的界面

Explicit属性 本属性忽略一个test和test fixture，直到它们显式的选择执行。如果test和test fixture在执行的过程中被发现，就忽略他们。所以，这样一来进度条显示为黄色，因为有test或test fixture忽略了。?例如：???1
?2????????????????????????[Test,Explicit]?
?3????????????????????????[Category("Exception")]?
?4????????????????????????[ExpectedException(typeof(DivideByZeroException))]?
?5????????????????????????public?void?DivideByZero()?
?6????????????????????????{?
?7????????????????????????????????????int?zero?=?0;?
?8????????????????????????????????????int?infinity?=?a/zero;?
?9????????????????????????????????????Assert.Fail("Should?have?gotten?an?exception");?
10????????????????????????}
11 ????为什么会设计成这样呢？原因是Ingore属性忽略了某个test或test fixture，那么他们你再想调用执行是不可能的。那么万一有一天我想调用被忽略的test或test fixture怎么办，就用Explicit属性了。我想这就是其中的原因吧。Expected Exception属性 ? 期望在运行时抛出一个期望的异常，如果是，则测试通过，否则不通过。参看下面的例子：?1[Test]?
?2[ExpectedException(typeofInvalidOperationException))]?
?3public?void?ExpectAnException()?
?4?{?
?5???int?zero?=?0;?
?6???int?infinity?=?a/zero;?
?7???Assert.Fail("Should?have?gotten?an?exception");?
?8???????????????????????
?9?}?
10 ??? 在本测试中，应该抛出DivideByZeroException，但是期望的是InvalidOperationException，所以不能通过。如果我们将[ExpectedException(typeof(InvalidOperationException))]改为[ExpectedException(typeof(DivideByZeroException))]，本测试通过。 5 . 测试生命周期合约 ?? 如果记得test case的定义,其中一个属性是测试的独立性或隔离性.SetUp/TearDown方法提供达到测试隔离性的目的.SetUp确保共享的资源在每个测试运行前正确初始化,TearDown确保没有运行测试产生的遗留副作用. TestFixtureSetUp/TestFixtureTearDown同样提供相同的目的,但是却在test fixture范围里,我们刚才描述的内容组成了测试框架的运行时容器(test runner)和你写的测试之间的生命周期合约(life-cycle contract). ?? 为了描述这个合约,我们写一个简单的测试来说明什么方法调用了,怎么合适调用的.这里是代码:

?1using?System;?2using?NUnit.Framework;?3[TestFixture]?4public?class?LifeCycleContractFixture?5{?6???[TestFixtureSetUp]?7???public?void?FixtureSetUp()?8???{?9??????Console.Out.WriteLine("FixtureSetUp");10???}11?12???[TestFixtureTearDown]13???public?void?FixtureTearDown()14???{15??????Console.Out.WriteLine("FixtureTearDown");16???}17???18???[SetUp]19???public?void?SetUp()20???{21??????Console.Out.WriteLine("SetUp");22???}2324???[TearDown]25???public?void?TearDown()26???{27??????Console.Out.WriteLine("TearDown");28???}29?30???[Test]31???public?void?Test1()32???{33??????Console.Out.WriteLine("Test?1");34???}3536???[Test]37???public?void?Test2()38???{39??????Console.Out.WriteLine("Test?2");40???}4142}4344

当编译和运行这个测试,可以在System.Console窗口看到下面的输出:

FixtureSetUpSetUpTest?1