BlackNest 1.0.2

BlackNest 1.0.2

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由 symentis GmbH 维护。

BlackNest 1.0.2

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BlackNest - 可重用测试

像规格一样测试

我们开始一个非常简单的函数。

func asTuple(_ int: Int) -> (Int, Int) {
  return (int, int * 2)
}

在为该函数编写测试之前，我们添加 spec。Spec 是一个函数，它接收 Input 和 Expected，它返回 Output 或抛出错误（返回类型是可选的）。

在函数内部，所有的断言都是由 DSL 执行的。对于 Input 和 Expected，你可以选择任何类型 - 实际类型、元组、可选类型。

/// This is the spec.
func doubleTuple(input: (Int), expect: (Int, Int)) throws -> (Int, Int) {
  // Act: do the tuple
  let subject = asTuple(input)

  // Assert: check all proofs
  try "First entry should still be the same"
    => subject.0 == expect.0
  try "Second entry should be double the first"
    => subject.1 == expect.1

  return subject
}

DSL 使得测试看起来像方程。易于阅读。现在我们执行不同的测试组合。

// Named arguments
expect(004, in:doubleTuple, is:(04, 08))
expect(008, in:doubleTuple, is:(08, 16))
expect(012, in:doubleTuple, is:(12, 24))
expect(100, in:doubleTuple, is:(100, 200))

// Named Arguments and Operators
expect(004, in: doubleTuple => (04, 08))
expect(008, in: doubleTuple => (08, 16))
expect(012, in: doubleTuple => (12, 24))
expect(100, in: doubleTuple => (100, 200))

// Operators only
expect(004 | doubleTuple => (04, 08))
expect(008 | doubleTuple => (08, 16))
expect(012 | doubleTuple => (12, 24))
expect(100 | doubleTuple => (100, 200))

如果其中一个 spec 失败，你会看到原因

error output by BlackNest

测试组合

再添加一个函数。

func asSum(_ tuple: Int, Int) -> Int {
  return tuple.0 + tuple.1
}

并为它添加另一个 spec。

func tupleSum(input: (Int, Int), expect: (Int)) throws -> Int {
  // Act: do the sum
  let subject = asSum(input)

  // Assert: check the spec
  try "sum calculation"
    => subject == expect

  return subject
}

现在您可以 组合两者。

函数的每次调用都可以返回和接收 单独的期望。返回值将传递到下一次测试运行。相同的代码 - 没有重复 - 并且再次 - 容易记住。

///
expect(04, in:doubleTuple, is:(04, 08)).then(tupleSum, is:12)
expect(08, in:doubleTuple, is:(08, 16)).then(tupleSum, is:24)
expect(12, in:doubleTuple, is:(12, 24)).then(tupleSum, is:36)

///
expect(004 | doubleTuple => (04, 08)).then(tupleSum => 12)
expect(008 | doubleTuple => (08, 16)).then(tupleSum => 24)
expect(012 | doubleTuple => (12, 24)).then(tupleSum => 36)

///
expect(
   4 |  doubleTuple => (04, 08)
     |~ tupleSum    => (12)
     |~ doubleTuple => (12, 24)
     |~ tupleSum    => (36)
 )

///
expect(4,
  in: doubleTuple ◦ tupleSum ◦ doubleTuple ◦ tupleSum,
  is: (04, 08)    • 12       • (12, 24)    • 36
)

更多示例

我们有一个“观鸟者”角色，并且根据他的技能显示不同的显示名称。

struct BirdWatcher {
  var name: String
  var experience: Int?
  var birdsSeen: Int?

  init(_ name: String) {
    self.name = name
  }

  var display: String {
    switch (experience, birdsSeen) {
    case let (y?, s?) where y > 10 && s > 100:
      return name + " - The Great Master."
    case let (y?, s?) where y > 5 && s > 50:
      return name + " - The Master."
    case let (y?, s?) where y < 1 && s < 1:
      return name + " - The Bloody Rookie."
    case let (y?, s?) where y < 5 && s < 5:
      return name + " - The Rookie."
    case let (y?, s?) where y < 1 && s > 10:
      return name + " - The Talent."
    default: return name
    }
  }
}

规范应提供关于你要测试内容的清晰画面。

/// typealias for Input
typealias BirdWatcherInput = (name: String, experience: Int?, birdsSeen: Int?)
/// typealias for Expected Data Tuple
typealias Data = (name: String, experience: Int?, birdsSeen: Int?, display: String)

/// the function that returns our breeding function.
func birdWatcher(_ input: BirdWatcherInput, expect: Data) throws {
  // Act:
  let subject = BirdWatcher(
    name: input.name,
    experience: input.experience,
    birdsSeen: input.birdsSeen
  )
  // Assert:
  try "name is correct"
    => subject.name == expect.name
  try "birdsSeen is correct"
    => subject.birdsSeen == expect.birdsSeen
  try "experience is correct"
    => subject.experience == expect.experience
  try "display is built correctly"
    => subject.display == expect.display
}

expect(("Burt", nil, 100) |  birdWatcher => ("Burt", nil, 100, "Burt"))
expect(("Burt", 20, 100)  |  birdWatcher => ("Burt", 20, 100, "Burt - The Master."))
expect(("Burt", 20, 0)    |  birdWatcher => ("Burt", 0, 100, "Burt - The Talent."))
expect(("Burt", nil, 0)   |  birdWatcher => ("Burt", 0, 0, "Burt - The Bloody Rookie."))

为什么选择BlackNest？

以黑窝金丝燕命名。

我们想要在测试中做的事情就是保护好珍贵的specRuns。不应该有任何裂缝。就是这样——照顾你的代码。

要求

Swift 4.2

安装

CocoaPods

pod 'BlackNest', '1.0.2'

致谢 & 许可证

Corridor 由 Symentis GmbH 拥有并维护。

开发人员：Elmar Kretzer Twitter

所有模块均基于MIT许可证发布。有关详细信息，请参阅LICENSE。