add test case and all green

Author: liufengyun

compiler/src/dotty/tools/dotc/transform/patmat/Space.scala

@@ -393,7 +393,10 @@ class SpaceEngine(implicit ctx: Context) extends SpaceLogic {
     case Bind(_, pat) => project(pat)
     case UnApply(fun, _, pats) =>
       if (fun.symbol.name == nme.unapplySeq)
-        projectSeq(pats)
+        if (fun.symbol.owner == scalaSeqFactoryClass)
+          projectSeq(pats)
+        else
+          Prod(pat.tpe.stripAnnots, fun.tpe.widen, fun.symbol, projectSeq(pats) :: Nil, irrefutable(fun))
       else
         Prod(pat.tpe.stripAnnots, fun.tpe.widen, fun.symbol, pats.map(project), irrefutable(fun))
     case Typed(pat @ UnApply(_, _, _), _) => project(pat)
@@ -484,7 +487,7 @@ class SpaceEngine(implicit ctx: Context) extends SpaceLogic {
           .map(_.info.asSeenFrom(mt.resultType, mt.resultType.classSymbol).widen)
       }
       else {
-        val resTp = mt.resultType.select(nme.get).resultType
+        val resTp = mt.resultType.select(nme.get).resultType.widen
         if (isUnapplySeq) scalaListType.appliedTo(resTp.argTypes.head) :: Nil
         else if (argLen == 0) Nil
         else productSelectors(resTp).map(_.info.asSeenFrom(resTp, resTp.classSymbol).widen)

tests/patmat/i3004.scala

@@ -0,0 +1,12 @@
+object O {
+  sealed trait Fruit
+  object Apple extends Fruit
+  object Banana extends Fruit
+  sealed class C(f1: Fruit, f2: Fruit)
+
+  object C {
+    def unapply(c: C): Some[Banana.type] = Some(Banana)
+  }
+
+  def m(c: C) = c match { case C(b) => b }
+}

tests/patmat/t9232.check

@@ -1 +1,2 @@
-13: Pattern Match Exhaustivity: Node2(), Node1(Foo(_))
+13: Pattern Match Exhaustivity: Node2()
+17: Pattern Match Exhaustivity: Node2(), Node1(Foo(Nil)), Node1(Foo(List(_, _*)))

tests/patmat/t9232.scala

@@ -11,6 +11,10 @@ case class Node2() extends Tree
 
 object Test {
   def transformTree(tree: Tree): Any = tree match {
-    case Node1(Foo(1)) => ???
+    case Node1(Foo(_: _*)) => ???
+  }
+
+  def transformTree2(tree: Tree): Any = tree match {
+    case Node1(Foo(1, _: _*)) => ???
   }
 }