patmatnew.scala

JAVA 语言的函数式编程扩展

trait Treez { self: Shmeez =>
  abstract class Tree
  case class Beez(i:Int) extends Tree
  case object HagbardCeline extends Tree
}

trait Shmeez extends AnyRef with Treez {
  val tree: Tree

  def foo = tree match {
    case Beez(2) => 1
    case HagbardCeline => 0
  }
}

import scala.testing.SUnit._

object Test extends TestConsoleMain {

  //just compilation
  def zipFun[a,b](xs:List[a], ys:List[b]):List[Pair[a,b]] = (Pair(xs,ys): @unchecked) match {
    // !!! case Pair(List(), _), Pair(_, List()) => List()
    case Pair(x :: xs1, y :: ys1) => Pair(x, y) :: zipFun(xs1, ys1)
  }

  def suite = new TestSuite(
      new TestSimpleIntSwitch,
      new SimpleUnapply,
      SeqUnapply,
      applyFromJcl,
      new Test717,
      TestGuards,
      TestEqualsPatternOpt,
      TestSequence01,
      TestSequence02,
      TestSequence03,
      TestSequence04,
      TestSequence05,
      TestSequence06,
      TestSequence07,
      TestSequence08,
      TestStream,
      new Test903,
      new Test1163_Order,
      new TestUnbox,
      Bug457,
      Bug508,
      Bug789,
      Bug995,
      Bug1093,
      Bug1094,
      ClassDefInGuard,
      Ticket2,
      Ticket11,
      Ticket37,
      Ticket44,
      Ticket346
    )

  class Foo(j:Int) {
    case class Bar(i:Int)
  }
  class SimpleUnapply extends TestCase("simpleUnapply") {
    override def runTest() { // from sortedmap, old version
      List((1,2)).head match {
        case kv @ Pair(key, _) => kv.toString + " " + key.toString
      }


    }
  }

  object SeqUnapply extends TestCase("seqUnapply") {
    case class SFB(i:int,xs:List[Int])
    override def runTest() { 
      List(1,2) match {
        case List(1) => assert(false, "wrong case")
        case List(1,2,xs @ _*) => assert(xs.isEmpty, "not empty")
        case Nil => assert(false, "wrong case")
      }
      SFB(1,List(1)) match {
        case SFB(_,List(x)) => assert(x==1)
        case SFB(_,_) => assert(false)
      }
    }
  }

  object applyFromJcl extends TestCase("applyFromJcl") {
    override def runTest {
      val p = (1,2)
        Some(2) match {
          case Some(p._2) =>         ;
          case _ => assert(false) ;
        }
    }
  }

  class TestSimpleIntSwitch extends TestCase("SimpleIntSwitch") {
    override def runTest() = {
      assertEquals("s1", 1, 1 match {
        case 3 => 3
        case 2 => 2
        case 1 => 1
        case 0 => 0
      })
      assertEquals("s2", 1, 1 match {
        case 1 => 1 
        case _ => 0
      })
      assertEquals("s2boxed", 1, (1:Any) match {
        case 1 => 1 
        case _ => 0
      })
      assertEquals("s3", 1, ("hello") match {
        case s:String => 1
        //case _        => 0 // unreachable!
      })
      val xyz: (int, String, boolean) = (1, "abc", true);
      assertEquals("s4", 1, xyz._1 match {
        case 1 => 1
        case _ => 0
      })
    }
  }
  class Test717 extends TestCase("#717 test path of case classes") {
    val foo1 = new Foo(1)
    val foo2 = new Foo(2)

    override def runTest() = {
      val res = (foo1.Bar(2):Any) match {
       case foo2.Bar(2) => false
       case foo1.Bar(2) => true
      }
      assertTrue("ok", res);
    }
  }

  object TestGuards extends TestCase("multiple guards for same pattern") with Shmeez {
    val tree:Tree = Beez(2)
    override def runTest = {
      val res = tree match {
        case Beez(x) if x == 3 => false
        case Beez(x) if x == 2 => true
      }
      assertTrue("ok", res);
      val ret = (Beez(3):Tree) match {
        case Beez(x) if x == 3 => true
        case Beez(x) if x == 2 => false
      }
      assertTrue("ok", ret);
    }
  }

  object TestEqualsPatternOpt extends TestCase("test EqualsPatternClass in combination with MixTypes opt, bug #1276") {
    val NoContext = new Object
    override def runTest {
      assertEquals(1,((NoContext:Any) match {
        case that : AnyRef if this eq that => 0
        case NoContext => 1
        case _ => 2
      }))
    }
  }

  object TestSequence01 extends TestCase("uno (all ignoring patterns on List)") {
    def doMatch(xs: List[String]): String = xs match {
      case List(_*) => "ok"
    }
    def doMatch2(xs: List[String]): List[String] = xs match {
      case List(_, rest @ _*) => rest.toList
    }
    override def runTest() {
      val list1 = List()
      assertEquals(doMatch(list1), "ok")
      val list2 = List("1","2","3")
      assertEquals(doMatch(list2), "ok")
      val list3 = List("1","2","3")
      assertEquals(doMatch2(list3), List("2","3"))
    }
  }


  object TestSequence02 extends TestCase("due (all ignoring patterns on Seq)") {
    def doMatch(l: Seq[String]): String = l match {
      case Seq(_*) => "ok"
    }
    override def runTest() {
      val list1 = List()
      assertEquals(doMatch(list1), "ok")
      val list2 = List("1", "2", "3")
      assertEquals(doMatch(list2), "ok")
      val array3 = Array[String]()
      assertEquals(doMatch(array3), "ok")
      val array4 = Array[String]("ga", "gu")
      assertEquals(doMatch(array4), "ok")
    }
  }

  object TestSequence03 extends TestCase("tre (right-ignoring patterns on List, defaults)") {
    def doMatch(xs: List[String]): String = xs match {
      case List(_,_,_,_*) => "ok"
      case _ => "not ok"
    }
    override def runTest() {
      val list1 = List()
      assertEquals(doMatch(list1), "not ok")
      val list2 = List("1","2","3")
      assertEquals(doMatch(list2), "ok")
      val list3 = List("1","2","3","4")
      assertEquals(doMatch(list3), "ok")
    }
  }


  object TestSequence04 extends TestCase("quattro (all- and right-ignoring pattern on case class w/ seq param)") {
    case class Foo(i: Int, chars: Char*)

    override def runTest() = {
      val a = Foo(0, 'a') match {
        case Foo(i, c, chars @ _*) => c
        case _ => null
      }
      assertEquals(a, 'a')

      val b = Foo(0, 'a') match {
        case Foo(i, chars @ _*) => 'b'
        case _ => null
      }
      assertEquals(b, 'b')
    }
  }

  object TestSequence05 extends TestCase("cinque (sealed case class with ignoring seq patterns)") {
    sealed abstract class Con;

    case class Foo() extends Con
    case class Bar(xs:Con*) extends Con
    
    override def runTest() {
      val res = (Bar(Foo()):Con) match {
        case Bar(xs@_*) => xs // this should be optimized away to a pattern Bar(xs)
        case _ => Nil
      }
      assertEquals("res instance"+res.isInstanceOf[Seq[Con] forSome { type Con }]+" res(0)="+res(0), true, res.isInstanceOf[Seq[Foo] forSome { type Foo}] && res(0) == Foo() )
    }
  }

  object TestSequence06 extends TestCase("sei (not regular) fancy guards / bug#644 ") {
    
    case class A(i: Any)
     
    def doMatch(x: Any, bla: int) = x match {
      case x:A if (bla==1) => 0
      case A(1) => 1
      case A(A(1)) => 2
    }

    override def runTest() {
      assertEquals(doMatch(A(null),1), 0)
      assertEquals(doMatch(A(1),2), 1)
      assertEquals(doMatch(A(A(1)),2), 2)
    }

  }

  object TestSequence07 extends TestCase("sette List of chars") {
    def doMatch1(xs: List[char]) = xs match {
      case List(x, y, _*) => x::y::Nil
    }
    def doMatch2(xs:List[char]) = xs match {
      case List(x, y, z, w) => List(z,w)
    }
    //def doMatch3(xs:List[char]) = xs match {
    //  case List(_*, z, w) => w::Nil
    //}
    def doMatch4(xs:Seq[Char]) = xs match {
      case Seq(x, y, _*) => x::y::Nil
      case Seq(x, y, z, w) => List(z,w) // redundant!
    }
    def doMatch5(xs:Seq[Char]) = xs match {
      case Seq(x, y, 'c', w @ _*) => x::y::Nil
      case Seq(x, y, z @ _*)    => z
    }
    def doMatch6(xs:Seq[Char]) = xs match {
      case Seq(x, 'b')            => x::'b'::Nil
      case Seq(x, y, z @ _*)    => z.toList
    }

    override def runTest() {
      assertEquals(List('a','b'), doMatch1(List('a','b','c','d')))
      assertEquals(List('c','d'), doMatch2(List('a','b','c','d')))
      //assertEquals(doMatch3(List('a','b','c','d')), List('d'))
      assertEquals(List('a','b'), doMatch4(List('a','b','c','d')))
      assertEquals(List('a','b'), doMatch5(List('a','b','c','d')))
      assertEquals(List('c','d'), doMatch6(List('a','b','c','d')))
    }
  }
 
  object TestSequence08 extends TestCase("backquoted identifiers in pattern") { 
    override def runTest() {
      val xs = List(2, 3)
      val ys = List(1, 2, 3) match {
        case x :: `xs` => xs
        case _ => Nil
      }
      assertEquals(xs, ys)
    }
  }


  object TestStream extends TestCase("unapply for Streams") {
    def sum(stream: Stream[int]): int =
      stream match {
        case Stream.empty => 0
        case Stream.cons(hd, tl) => hd + sum(tl)
      }
    
    val str: Stream[int] = Stream.fromIterator(List(1,2,3).elements)

    def runTest() = assertEquals(sum(str), 6)
  }
  
  class Test1163_Order extends TestCase("bug#1163 order of temps must be preserved") {
    abstract class Function
    case class Var(n: String) extends Function
    case class Const(v: double) extends Function
    
    def f(): (Function, Function) = {
      (Var("x"): Function, Var("y"): Function) match {
        case (Const(v), Const(w)) => throw new Error
        case (leftOne, Var("z")) => throw new Error
        case (leftTwo, rightTwo) => (leftTwo, rightTwo) // was giving "y","x"
      }
    }
    
    def flips(l: List[int]): int = (l: @unchecked) match { 
      case 1 :: ls => 0
      case n :: ls => flips((l take n reverse) ::: (l drop n)) + 1
    }

    def runTest() =  assertEquals("both", (Var("x"),Var("y")), f) 
  }

  class TestUnbox extends TestCase("unbox") {
    override def runTest() {
      val xyz: (int, String, boolean) = (1, "abc", true)
      xyz._1 match {
        case 1 => "OK"
        case 2 => assert(false); "KO"
        case 3 => assert(false); "KO"
      }
    }
  }

  class Test806_818 { // #806, #811 compile only -- type of bind
    // bug811
    trait Core {
      trait NodeImpl;
      trait OtherImpl extends NodeImpl;
      trait DoubleQuoteImpl extends NodeImpl;
      def asDQ(node : OtherImpl) = node match {
	case dq : DoubleQuoteImpl => dq;
      }
    }
    
    trait IfElseMatcher { 
      type Node <: NodeImpl;
      trait NodeImpl;
      trait IfImpl; 
      private def coerceIf(node : Node) = node match {
        case node : IfImpl => node; // var node is of type Node with IfImpl!
        case _ => null;
      }
    }    
  }


  class Person(_name : String, _father : Person) {
    def name = _name
    def father = _father
  }

  object PersonFather {
    def unapply(p : Person) : Option[Person]  = 
      if (p.father == null)
        None
      else
  	    Some(p.father)
  }

  class Test903 extends TestCase("bug903") {

  override def runTest = {
    val p1 = new Person("p1",null)
    val p2 = new Person("p2",p1)
    assertEquals((p2.name, p1.name), p2 match {
      case aPerson@PersonFather(f) => (aPerson.name,f.name)
      case _ => "No father"
    })
  }
  }


  object Test1253  { // compile-only
    def foo(t : (Int, String)) = t match {
      case (1, "") => throw new Exception
      case (r, _) => throw new Exception(r.toString)
    }
  }

  object Foo1258 {
    case object baz
    def foo(bar : AnyRef) = {
      val Baz = baz
      bar match {
        case Baz => ()
      }
    }
  }

  object Foo1 {
    class Bar1(val x : String)
    def p(b : Bar1) = Console.println(b.x)
    
    def unapply(s : String) : Option[Bar1] =
      Some(new Bar1(s))
  }
  
  object bug881 extends TestCase("881") {
    override def runTest = {
      "baz" match {
        case Foo1(x) =>
          Foo1.p(x)
      }
    }
  }


  // these are exhaustive matches
  //   should not generate any warnings
  def f[A](z:(Option[A],Option[A])) = z match {
    case Pair(None,Some(x)) => 1
    case Pair(Some(x),None ) => 2
    case Pair(Some(x),Some(y)) => 3
    case _ => 4
  }
  
  def g1[A](z:Option[List[A]]) = z match {
    case Some(Nil) => true    
    case Some(x::Nil) => true  
    case _ => true
  }
  
  def g2[A](z:Option[List[A]]) = z match {
    case Some(x::Nil) => true  
    case Some(_) => false
    case _ => true
  }
  
  def h[A](x: (Option[A],Option[A])) = x match {
    case Pair(None,_:Some[_]) => 1
    case Pair(_:Some[_],None ) => 2
    case Pair(_:Some[_],_:Some[_]) => 3
    case _ => 4
  }

  def j = (List[Int](), List[Int](1)) match {
    case (Nil, _) => 'a'