Deprecated case classes inheriting from other c...

Deprecated case classes inheriting from other case classes, and updated
all the tests which did so.

12 files changed, 20 insertions, 72 deletions

diff --git a/src/compiler/scala/tools/nsc/typechecker/Typers.scala b/src/compiler/scala/tools/nsc/typechecker/Typers.scala
index d9471c6008..790e7e99ca 100644
--- a/src/compiler/scala/tools/nsc/typechecker/Typers.scala
+++ b/src/compiler/scala/tools/nsc/typechecker/Typers.scala
@@ -1143,6 +1143,17 @@ trait Typers { self: Analyzer =>
           if (psym hasFlag FINAL) {
             error(parent.pos, "illegal inheritance from final "+psym)
           }
+          // XXX I think this should issue a sharper warning of some kind like
+          // "change your code now!" as there are material bugs (which will not be fixed)
+          // associated with case class inheritance.
+          if ((context.owner hasFlag CASE) && !phase.erasedTypes) {
+            for (ancestor <- parent.tpe.baseClasses find (_ hasFlag CASE))
+              unit.deprecationWarning(parent.pos, (
+                "case class `%s' has case class ancestor `%s'.  This has been deprecated " +
+                "for unduly complicating both usage and implementation.  You should instead " +
+                "use extractors for pattern matching on non-leaf nodes." ).format(context.owner, ancestor)
+              )
+          }
           if (psym.isSealed && !phase.erasedTypes) {
             if (context.unit.source.file != psym.sourceFile)
               error(parent.pos, "illegal inheritance from sealed "+psym)
diff --git a/test/files/neg/bug473.scala b/test/files/neg/bug473.scala
index 831f647f71..4c434b9fc0 100644
--- a/test/files/neg/bug473.scala
+++ b/test/files/neg/bug473.scala
@@ -1,3 +1,3 @@
-case class Foo(x: Foo)
+class Foo(x: Foo)
 case object Bar extends Foo(null)
 case object Voop extends Foo(Voop)
\ No newline at end of file
diff --git a/test/files/pos/bug1087.scala b/test/files/pos/bug1087.scala
deleted file mode 100644
index 19d62116c6..0000000000
--- a/test/files/pos/bug1087.scala
+++ /dev/null
@@ -1,2 +0,0 @@
-case class Foo
-case class Prd (pred : Char => Boolean) extends Foo
diff --git a/test/files/pos/jesper.scala b/test/files/pos/jesper.scala
deleted file mode 100644
index b2a027b0f2..0000000000
--- a/test/files/pos/jesper.scala
+++ /dev/null
@@ -1,30 +0,0 @@
-object Pair {
- sealed trait Pair {
-   type First
-   type Second <: Pair
- }
-
- case class End extends Pair {
-   type First = Nothing
-   type Second = End
-
-   def ::[T](v : T) : Cons[T, End] = Cons(v, this)
- }
-
- case object End extends End
-
- final case class Cons[T1, T2 <: Pair](_1 : T1, _2 : T2) extends Pair {
-   type First = T1
-   type Second = T2
-
-   def ::[T](v : T) : Cons[T, Cons[T1, T2]] = Cons(v, this)
-   def find[T](implicit finder : Cons[T1, T2] => T) = finder(this)
- }
-
- implicit def findFirst[T1, T2 <: Pair] : Cons[T1, T2] => T1 = (p : Cons[T1, T2]) => p._1
- implicit def findSecond[T, T1, T2 <: Pair](implicit finder : T2 => T) : Cons[T1, T2] => T = (p : Cons[T1, T2]) => finder(p._2)
-
- val p : Cons[Int, Cons[Boolean, End]] = 10 :: false :: End
-// val x : Boolean = p.find[Boolean](findSecond(findFirst))
- val x2 : Boolean = p.find[Boolean]  // Doesn't compile
-}
diff --git a/test/files/pos/t0710.scala b/test/files/pos/t0710.scala
index 4512a101d9..fb440bc796 100644
--- a/test/files/pos/t0710.scala
+++ b/test/files/pos/t0710.scala
@@ -1,6 +1,6 @@
 object t0710 {
   def method {
-    sealed case class Parent
+    sealed class Parent
     case object Child extends Parent
     val x: Parent = Child
     x match {
diff --git a/test/files/pos/t1087.scala b/test/files/pos/t1087.scala
deleted file mode 100644
index bb0d7012c1..0000000000
--- a/test/files/pos/t1087.scala
+++ /dev/null
@@ -1,3 +0,0 @@
-case class Foo
-case class Prd (pred : Char => Boolean) extends Foo
-
diff --git a/test/files/pos/typesafecons.scala b/test/files/pos/typesafecons.scala
index b2a027b0f2..5243280160 100644
--- a/test/files/pos/typesafecons.scala
+++ b/test/files/pos/typesafecons.scala
@@ -4,7 +4,7 @@ object Pair {
    type Second <: Pair
  }
 
- case class End extends Pair {
+ class End extends Pair {
    type First = Nothing
    type Second = End
 
diff --git a/test/files/run/canEqualCaseClasses.scala b/test/files/run/canEqualCaseClasses.scala
deleted file mode 100644
index b1c3eb91de..0000000000
--- a/test/files/run/canEqualCaseClasses.scala
+++ /dev/null
@@ -1,23 +0,0 @@
-object Test {
-  case class Foo(x: Int)
-  case class Bar(y: Int) extends Foo(y)
-  case class Nutty() {
-    override def canEqual(other: Any) = true
-  }
-
-  def assertEqual(x: AnyRef, y: AnyRef) =
-    assert((x == y) && (y == x) && (x.hashCode == y.hashCode))
-
-  def assertUnequal(x: AnyRef, y: AnyRef) =
-    assert((x != y) && (y != x))
-
-  def main(args: Array[String]): Unit = {
-    assertEqual(Foo(5), Foo(5))
-    assertEqual(Bar(5), Bar(5))
-    assertUnequal(Foo(5), Bar(5))
-
-    // in case there's an overriding implementation
-    assert(Nutty() canEqual (new AnyRef))
-    assert(!(Foo(5) canEqual (new AnyRef)))
-  }
-}
diff --git a/test/files/run/caseclasses.scala b/test/files/run/caseclasses.scala
index 56fe6dad96..ed5643a709 100644
--- a/test/files/run/caseclasses.scala
+++ b/test/files/run/caseclasses.scala
@@ -2,8 +2,6 @@ case class Foo(x: Int)(y: Int)
 
 case class Bar
 
-case class Baz(override val x: Int, y: Int) extends Foo(x)(y)
-
 abstract class Base
 abstract case class Abs(x: Int) extends Base
 
@@ -30,10 +28,6 @@ object Test extends Application {
     case Foo(1) => Console.println("OK")
     case Bar() => Console.println("NO")
   }
-  (Baz(1, 2): AnyRef) match {
-    case Baz(1, 2) => ;
-    case Bar() => Console.println("NO")
-  }
   try {
     Bar() productElement 3
     throw new NullPointerException("duh")
diff --git a/test/files/run/patmatnew.scala b/test/files/run/patmatnew.scala
index 34bd024b29..c78fceb96b 100644
--- a/test/files/run/patmatnew.scala
+++ b/test/files/run/patmatnew.scala
@@ -928,7 +928,7 @@ override def runTest() {
 
   object Ticket710 {  // compile-only
     def method {
-      sealed case class Parent()
+      sealed class Parent()
       case object Child extends Parent()
       val x: Parent = Child
       x match {
diff --git a/test/files/run/t0607.scala b/test/files/run/t0607.scala
index afc7ff9b46..5601494dec 100644
--- a/test/files/run/t0607.scala
+++ b/test/files/run/t0607.scala
@@ -1,7 +1,7 @@
 object Test extends Application {
-  case class A
-  case class B extends A
+  case class A()
+  class B extends A() { override def toString() = "B()" }
   println(A())
-  println(B())
+  println(new B())
 }
 
diff --git a/test/files/run/t0883.scala b/test/files/run/t0883.scala
index 5cd4418f5b..b9d71702d8 100755
--- a/test/files/run/t0883.scala
+++ b/test/files/run/t0883.scala
@@ -1,4 +1,5 @@
-case class Foo(name: String)
+object Foo { def apply(x: String) = new Foo(x) }
+class Foo(name: String)
 case object Bar extends Foo("Bar")
 case class Baz extends Foo("Baz")
 object Test extends Application {