書寫測(cè)試用例一個(gè)步驟是書寫測(cè)試的預(yù)期結(jié)果。

函數(shù)化

Spec2 中缺省 Specification Trait 是函數(shù)化的，也就是說(shuō) Example 的 Result 值為代碼中的最后一條語(yǔ)句提供。比如下面的示例，永遠(yuǎn)不會(huì)失敗，這是本例的第一個(gè)測(cè)試的結(jié)果給丟掉了。

"my example on strings" ! e1           // will never fail!

def e1 = {
  "hello" must have size(10000)        // because this expectation will not be returned,...
  "hello" must startWith("hell")
}

因此正確的寫法為：

"my example on strings" ! e1           // will fail

def e1 = "hello" must have size(10000) and
                           startWith("hell")

Thrown

上面的函數(shù)化需要仔細(xì)指明所有的期望，有時(shí)你可能覺得這樣很麻煩，比如還是用什么的那個(gè)不會(huì)失敗的例子：

import org.specs2._

class HelloWorldAcceptanceSpec extends Specification  { def is = s2"""

 This is a specification to check the 'Hello world' string

  "my example on strings"    $e1
                                                                 """

  def e1 = {
    "hello" must have size(10000)        // because this expectation will not be returned,...
    "hello" must startWith("hell")
  }
}

這個(gè)例子來(lái)執(zhí)行不會(huì)報(bào)失敗，我們希望在執(zhí)行“hello” must have size(10000）報(bào)錯(cuò)，不繼續(xù)執(zhí)行下面的測(cè)試，此時(shí)我們可以使用 org.specs2.matcher.ThrownExpectations，此時(shí)如果將這個(gè) Trait 混合到定義的規(guī)范中，所有沒有達(dá)到期望值的測(cè)試都會(huì)拋出 FailureException 異常，Example 之后的測(cè)試也不執(zhí)行，比如修改后代碼：

import org.specs2._
import org.specs2.matcher.ThrownExpectations

class HelloWorldAcceptanceSpec extends Specification with ThrownExpectations { def is = s2"""

 This is a specification to check the 'Hello world' string

  "my example on strings"    $e1
                                                                 """

  def e1 = {
    "hello" must have size(10000)        // because this expectation will not be returned,...
    "hello" must startWith("hell")
  }
}

這個(gè)測(cè)試的第一個(gè)檢測(cè)“hello” must have size(10000)失敗，整個(gè) Example 失敗，后續(xù)的測(cè)試也不會(huì)執(zhí)行。