Fix #581: add tests

Author: liufengyun

compiler/src/dotty/tools/dotc/transform/PatternMatcher.scala

@@ -262,8 +262,6 @@ object PatternMatcher {
 
       /** Plan for matching the sequence in `getResult` against sequence elements
        *  and a possible last varargs argument `args`.
-       *
-       *  `getResult` could also be a product, where the last element is a sequence of elements.
        */
       def unapplySeqPlan(getResult: Symbol, args: List[Tree]): Plan = args.lastOption match {
         case Some(VarArgPattern(arg)) =>

tests/pending/run/value-class-extractor-seq.check

@@ -6,20 +6,22 @@ final class StringExtract(val s: String) extends AnyVal {
   def apply(idx: Int): Char       = s charAt idx
   def head: Char                  = s charAt 0
   def tail: String                = s drop 1
-  def drop(n: Int): StringExtract = new StringExtract(s drop n)
+  def drop(n: Int): Seq[Char]     = toSeq.drop(n)
+  def toSeq: Seq[Char]            = s.toSeq
 
   override def toString = s
 }
 
 final class ThreeStringExtract(val s: String) extends AnyVal {
-  def isEmpty                                      = (s eq null) || (s == "")
-  def get: (List[Int], Double, ThreeStringExtract) = ((s.length :: Nil, s.length.toDouble, this))
-  def length                                       = s.length
-  def lengthCompare(n: Int)                        = s.length compare n
-  def apply(idx: Int): Char                        = s charAt idx
-  def head: Char                                   = s charAt 0
-  def tail: String                                 = s drop 1
-  def drop(n: Int): ThreeStringExtract             = new ThreeStringExtract(s drop n)
+  def isEmpty                             = (s eq null) || (s == "")
+  def get: (List[Int], Double, Seq[Char]) = ((s.length :: Nil, s.length.toDouble, toSeq))
+  def length                              = s.length
+  def lengthCompare(n: Int)               = s.length compare n
+  def apply(idx: Int): Char               = s charAt idx
+  def head: Char                          = s charAt 0
+  def tail: String                        = s drop 1
+  def drop(n: Int): Seq[Char]             = toSeq.drop(n)
+  def toSeq: Seq[Char]                    = s.toSeq
 
   override def toString = s
 }

tests/pending/run/string-extractor.check renamed to tests/run/string-extractor.check

@@ -0,0 +1,3 @@
+Bip(1, 2, 3)
+Bip(1, 2, c : WrappedArray(3, 4, 5): _*)
+class [I

tests/pending/run/string-extractor.scala renamed to tests/run/string-extractor.scala

@@ -2,7 +2,7 @@ import scala.runtime.ScalaRunTime.stringOf
 
 final class ArrayOpt[T](val xs: Array[T]) extends AnyVal {
   def isEmpty = xs == null
-  def get = xs
+  def get: Seq[T] = xs.toSeq
 }
 
 object Bip {
@@ -44,7 +44,7 @@ object Bip {
 object Test {
   def f(x: Any) = x match {
     case Bip(a, b, c)      => s"Bip($a, $b, $c)"
-    case Bip(a, b, c : _*) => s"Bip($a, $b, c @ ${stringOf(c)}: _*)"
+    case Bip(a, b, c : _*) => s"Bip($a, $b, c : ${stringOf(c)}: _*)"
     case _                 => "" + x.getClass
   }