将 Scalacheck 与 Inside trait 结合使用

Question

我有一个非常简单的场景：测试作为参数传递到案例中的任何一对长度为 10 的随机字符串 class 对（正在测试的自定义字符串）应该相同。

class ExercisesPropSpec extends PropSpec with Checkers with Matchers with Inside{

  import Exercises._

  lazy val genPairs = for {
    left <- Gen.listOfN(10, Gen.alphaChar)
    right <- Gen.listOfN(10, Gen.alphaChar)
  } yield (left.mkString, right.mkString)

  property("pattern match tuples of alphanumerics to our custom pair class"){
    forAll(genPairs) {case (left: String, right: String) =>
      val pair = Pair(left, right)
      inside(pair) { case Pair(firstName, lastName) =>
        firstName shouldEqual(left)
        lastName shouldEqual(right)
      }
    }
  }
}

然而，当我从 sbt 运行 testOnly *ExercisesPropSpec 时，我得到了这个编译错误：

Compiling 1 Scala source to /home/vgorcinschi/ideaProjects/Learning Concurrent Programming in Scala/chapter01_introduction/target/scala-2.12/test-classes ...
[error] ~/ideaProjects/Learning Concurrent Programming in Scala/chapter01_introduction/src/test/scala/org/learningconcurrency/ExercisesPropSpec.scala:18:28: No implicit view available from org.scalatest.Assertion => org.scalacheck.Prop.
[error]     check(forAll(genPairs) {case (left: String, right: String) =>
[error]                            ^

A note 在 scalacheck-cookbook 中说

what the error message indicates is that our property check is not evaluating in terms of Boolean logic

我希望最后的内部块应该返回布尔值。如果您能指出我在理解基于属性的测试或在此实现中使用 Inside trait 时遗漏了什么，我将不胜感激。

Answer 1

你只需要写

firstName == left && lastName == right

相反。

（如果 shouldEqual 做了 return Boolean，firstName shouldEqual(left) 的结果将被丢弃。）

将 Scalacheck 与 Inside trait 结合使用

Using Scalacheck with Inside trait

scala

scalatest

scalacheck