使用 specs 测试

由 Shaodengdeng 创建， 最后一次修改 2016-08-12 使用 specs 测试扩展规格让我们直接开始。import org.specs._object ArithmeticSpec extends Specification { "Arithmetic" should { "add two numbers" in { 1 + 1 mustEqual 2 } "add three numbers" in { 1 + 1 + 1 mustEqual 3 } }}Arithmetic（算术） 是一个 规范约束下的系统add（加） 是一个上下文。add two numbers（两个数相加），和 add three numbers（三个数字相加） 是例子。mustEqual 表示 预期1 mustEqual 1 是编写实际测试前使用的一种常见的预期占位符。所有的测试用例都应该至少有一个预期。复制注意到两个测试都是怎样将 add 加在其名称中的吗？我们可以通过嵌套预期摆脱这种重复。import org.specs._object ArithmeticSpec extends Specification { "Arithmetic" should { "add" in { "two numbers" in { 1 + 1 mustEqual 2 } "three numbers" in { 1 + 1 + 1 mustEqual 3 } } }}执行模型object ExecSpec extends Specification { "Mutations are isolated" should { var x = 0 "x equals 1 if we set it." in { x = 1 x mustEqual 1 } "x is the default value if we don't change it" in { x mustEqual 0 } }}Setup, TeardowndoBefore & doAfter"my system" should { doBefore { resetTheSystem() /** user-defined reset function */ } "mess up the system" in {...} "and again" in {...} doAfter { cleanThingsUp() }}注意 doBefore/doAfter 只能运行在叶子用例上。doFirst & doLastdoFirst/doLast 用来做一次性的设置。（需要例子，我不使用这个）"Foo" should { doFirst { openTheCurtains() } "test stateless methods" in {...} "test other stateless methods" in {...} doLast { closeTheCurtains() }}Matchers你有数据，并且想要确保它是正确的。让我们看看最常用的匹配器是如何帮助你的。mustEqual我们已经看到几个 mustEqual 的例子了。1 mustEqual 1"a" mustEqual "a"引用相等，值相等。序列中的元素val numbers = List(1, 2, 3)numbers must contain(1)numbers must not contain(4)numbers must containAll(List(1, 2, 3))numbers must containInOrder(List(1, 2, 3))List(1, List(2, 3, List(4)), 5) must haveTheSameElementsAs(List(5, List(List(4), 2, 3), 1))映射中的元素map must haveKey(k)map must notHaveKey(k)map must haveValue(v)map must notHaveValue(v)数字a must beGreaterThan(b)a must beGreaterThanOrEqualTo(b)a must beLessThan(b)a must beLessThanOrEqualTo(b)a must beCloseTo(b, delta)Optionsa must beNonea must beSome[Type]a must beSomethinga must beSome(value)throwAa must throwA[WhateverException]这是一个针对try\catch块中有异常抛出的用例的简写。您也可以期望一个特定的消息a must throwA(WhateverException("message"))您也可以匹配异常：a must throwA(new Exception) like { case Exception(m) => m.startsWith("bad")}编写你自己的匹配器import org.specs.matcher.Matcher作为一个不变量"A matcher" should { "be created as a val" in { val beEven = new Matcher[Int] { def apply(n: => Int) = { (n % 2 == 0, "%d is even".format(n), "%d is odd".format(n)) } } 2 must beEven }}契约是返回一个包含三个值的元组，分别是期望是否为真、为真时的消息和为假时的消息。作为一个样本类case class beEven(b: Int) extends Matcher[Int]() { def apply(n: => Int) = (n % 2 == 0, "%d is even".format(n), "%d is odd".format(n))}使用样本类可以增加代码的重用性。Mocksimport org.specs.Specificationimport org.specs.mock.Mockitoclass Foo[T] { def get(i: Int): T}object MockExampleSpec extends Specification with Mockito { val m = mock[Foo[String]] m.get(0) returns "one" m.get(0) there was one(m).get(0) there was no(m).get(1)}参考 Using MockitoSpiesSpies（间谍）可以对真正的对象做一些“局部 mocking”：val list = new LinkedList[String]val spiedList = spy(list)// methods can be stubbed on a spyspiedList.size returns 100// other methods can also be usedspiedList.add("one")spiedList.add("two")// and verification can happen on a spythere was one(spiedList).add("one")然而，使用间谍可能会出现非常诡异的情况：// if the list is empty, this will throws an IndexOutOfBoundsExceptionspiedList.get(0) returns "one"这里必须使用 doReturn ：doReturn("one").when(spiedList).get(0)在 sbt 中运行单个 specs> test-only com.twitter.yourservice.UserSpec将只运行那个规范。> ~ test-only com.twitter.yourservice.UserSpec将在一个循环中运行该测试，文件的每一次修改都将触发测试运行。