斯卡拉規格單元測試

Question

我已經得到了以下類，我想寫一些Spec測試用例，但我真的很陌生，我不知道如何開始。我的班級喜歡這樣：

class Board{ 

    val array = Array.fill(7)(Array.fill(6)(None:Option[Coin])) 

    def move(x:Int, coin:Coin) { 
    val y = array(x).indexOf(None) 
    require(y >= 0) 
    array(x)(y) = Some(coin) 
    } 

    def apply(x: Int, y: Int):Option[Coin] = 
    if (0 <= x && x < 7 && 0 <= y && y < 6) array(x)(y) 
    else None 

    def winner: Option[Coin] = winner(Cross).orElse(winner(Naught)) 

    private def winner(coin:Coin):Option[Coin] = { 
    val rows = (0 until 6).map(y => (0 until 7).map(x => apply(x,y))) 
    val cols = (0 until 7).map(x => (0 until 6).map(y => apply(x,y))) 
    val dia1 = (0 until 4).map(x => (0 until 6).map(y => apply(x+y,y))) 
    val dia2 = (3 until 7).map(x => (0 until 6).map(y => apply(x-y,y))) 

    val slice = List.fill(4)(Some(coin)) 
    if((rows ++ cols ++ dia1 ++ dia2).exists(_.containsSlice(slice))) 
     Some(coin) 
    else None 
    } 

    override def toString = { 
    val string = new StringBuilder 
    for(y <- 5 to 0 by -1; x <- 0 to 6){ 
     string.append(apply(x, y).getOrElse("_")) 
     if (x == 6) string.append ("\n") 
     else string.append("|") 
    } 
    string.append("0 1 2 3 4 5 6\n").toString 
    } 
} 

謝謝！

Answer 1

我建議你把所有的代碼都扔出去 - 好吧，保存在某個地方，但是使用TDD從零開始。

Specs2網站有很多關於如何編寫測試的例子，但是使用TDD - 測試驅動設計 - 來做到這一點。至少可以說，在事實之後添加測試並不理想。

因此，想想你想要處理的最簡單的功能最簡單的情況，寫一個測試，看到它失敗，編寫代碼來修復它。必要時重構，並重復下一個最簡單的情況。

如果您需要一般TDD的幫助，我衷心贊同Clean Coders上提供的有關TDD的視頻。至少，請看第二部分，鮑勃·馬丁寫下了從設計到結束的全班TDD風格。

如果您知道如何進行一般測試但對Scala或Specs感到困惑，請更具體地瞭解您的問題。

Answer 2

我只能用丹尼爾的建議，因爲使用TDD最終會得到更實用的API。

我也認爲你的應用程序可以很好地測試specs2和ScalaCheck的混合。這裏一個規範的草案，讓你開始：

import org.specs2._ 
    import org.scalacheck.{Arbitrary, Gen} 

    class TestSpec extends Specification with ScalaCheck { def is = 

    "moving a coin in a column moves the coin to the nearest empty slot" ! e1^ 
    "a coin wins if"             ^
     "a row contains 4 consecutive coins"        ! e2^ 
     "a column contains 4 consecutive coins"       ! e3^ 
     "a diagonal contains 4 consecutive coins"       ! e4^ 
                     end 

    def e1 = check { (b: Board, x: Int, c: Coin) => 
     try { b.move(x, c) } catch { case e =>() } 
     // either there was a coin before somewhere in that column 
     // or there is now after the move 
     (0 until 6).exists(y => b(x, y).isDefined) 
    } 

    def e2 = pending 
    def e3 = pending 
    def e4 = pending 

    /** 
    * Random data for Coins, x position and Board 
    */ 
    implicit def arbitraryCoin: Arbitrary[Coin]  = Arbitrary { Gen.oneOf(Cross,  Naught) } 
    implicit def arbitraryXPosition: Arbitrary[Int] = Arbitrary { Gen.choose(0, 6) } 
    implicit def arbitraryBoardMove: Arbitrary[(Int, Coin)] = Arbitrary { 
     for { 
     coin <- arbitraryCoin.arbitrary 
     x <- arbitraryXPosition.arbitrary 
     } yield (x, coin) 
    } 
    implicit def arbitraryBoard: Arbitrary[Board] = Arbitrary { 
     for { 
     moves <- Gen.listOf1(arbitraryBoardMove.arbitrary) 
     } yield { 
     val board = new Board 
     moves.foreach { case (x, coin) => 
      try { board.move(x, coin) } catch { case e =>() }} 
      board 
     } 
    } 


    } 

    object Cross extends Coin { 
    override def toString = "x" 
    } 
    object Naught extends Coin { 
    override def toString = "o" 
    } 
    sealed trait Coin 

的e1財產我實現是不是真實的東西，因爲它並沒有真正檢查我們感動的硬幣到最近空插槽，這就是你的代碼和API的建議。您還需要更改生成的數據，以便生成交替x和o的板。這應該是學習如何使用ScalaCheck的好方法！