Tighter type checking rules for structural type...

Tighter type checking rules for structural types that fix issues #967,
#1004, #1388, #1494, and #1906.

1 files changed, 32 insertions, 23 deletions

diff --git a/test/files/neg/structural.scala b/test/files/neg/structural.scala
index dd8817d902..181a32654e 100644
--- a/test/files/neg/structural.scala
+++ b/test/files/neg/structural.scala
@@ -1,23 +1,23 @@
 object Test extends Application {
 
-  def f(x: { type D; def m: D }) = x.m
+  def f(x: { type D; def m: D }): Null = null
 
   class Tata
 
-  abstract class Toto[A <: AnyRef] {
-    type B <: AnyRef
+  abstract class Toto[A <: Object] {
+    type B <: Object
 
-    def f1[C <: AnyRef](x: AnyRef{ type D <: AnyRef; def m[E >: Null <: AnyRef](x: A): AnyRef; val x: A }) = x.m[Tata](x.x) //fail
-    def f2[C <: AnyRef](x: AnyRef{ type D <: AnyRef; def m[E >: Null <: AnyRef](x: B): AnyRef; val x: B }) = x.m[Tata](x.x) //fail
-    def f3[C <: AnyRef](x: AnyRef{ type D <: AnyRef; def m[E >: Null <: AnyRef](x: C): AnyRef; val x: C }) = x.m[Tata](x.x) //fail
-    def f4[C <: AnyRef](x: AnyRef{ type D <: AnyRef; def m[E >: Null <: AnyRef](x: D): AnyRef; val x: D }) = x.m[Tata](x.x) //suceed
-    def f5[C <: AnyRef](x: AnyRef{ type D <: AnyRef; def m[E >: Null <: AnyRef](x: E): AnyRef; val x: Tata }) = x.m[Tata](x.x) //suceed
+    def f1[C <: Object](x: Object{ type D <: Object; def m[E >: Null <: Object](x: A): Object; val x: A }) = x.m[Tata](x.x) //fail
+    def f2[C <: Object](x: Object{ type D <: Object; def m[E >: Null <: Object](x: B): Object; val x: B }) = x.m[Tata](x.x) //fail
+    def f3[C <: Object](x: Object{ type D <: Object; def m[E >: Null <: Object](x: C): Object; val x: C }) = x.m[Tata](x.x) //fail
+    def f4[C <: Object](x: Object{ type D <: Object; def m[E >: Null <: Object](x: D): Object; val x: D }) = x.m[Tata](x.x) //fail
+    def f5[C <: Object](x: Object{ type D <: Object; def m[E >: Null <: Object](x: E): Object; val x: Tata }) = x.m[Tata](x.x) //suceed
 
-    def f6[C <: AnyRef](x: AnyRef{ type D <: AnyRef; def m[E >: Null <: AnyRef](x: AnyRef): A }) = x.m[Tata](new AnyRef) //suceed
-    def f7[C <: AnyRef](x: AnyRef{ type D <: AnyRef; def m[E >: Null <: AnyRef](x: AnyRef): B }) = x.m[Tata](new AnyRef) //suceed
-    def f8[C <: AnyRef](x: AnyRef{ type D <: AnyRef; def m[E >: Null <: AnyRef](x: AnyRef): C }) = x.m[Tata](new AnyRef) //suceed
-    def f9[C <: AnyRef](x: AnyRef{ type D <: AnyRef; def m[E >: Null <: AnyRef](x: AnyRef): D }) = x.m[Tata](new AnyRef) //suceed
-    def f0[C <: AnyRef](x: AnyRef{ type D <: AnyRef; def m[E >: Null <: AnyRef](x: AnyRef): E }) = x.m[Tata](new AnyRef) //suceed
+    def f6[C <: Object](x: Object{ type D <: Object; def m[E >: Null <: Object](x: Object): A }) = x.m[Tata](null) //suceed
+    def f7[C <: Object](x: Object{ type D <: Object; def m[E >: Null <: Object](x: Object): B }) = x.m[Tata](null) //suceed
+    def f8[C <: Object](x: Object{ type D <: Object; def m[E >: Null <: Object](x: Object): C }) = x.m[Tata](null) //suceed
+    def f9[C <: Object](x: Object{ type D <: Object; def m[E >: Null <: Object](x: Object): D }) = x.m[Tata](null) //fail
+    def f0[C <: Object](x: Object{ type D <: Object; def m[E >: Null <: Object](x: Object): E }) = x.m[Tata](null) //suceed
 
   }
 
@@ -26,20 +26,29 @@ object Test extends Application {
     type B = Tata
   }
 
-  toto.f1[Tata](new AnyRef{ type D = Tata; def m[E >: Null <: AnyRef](x: Tata): AnyRef = null; val x = tata })
-  toto.f2[Tata](new AnyRef{ type D = Tata; def m[E >: Null <: AnyRef](x: Tata): AnyRef = null; val x = tata })
-  toto.f3[Tata](new AnyRef{ type D = Tata; def m[E >: Null <: AnyRef](x: Tata): AnyRef = null; val x = tata })
-  toto.f4[Tata](new AnyRef{ type D = Tata; def m[E >: Null <: AnyRef](x: D): AnyRef = null; val x = tata })
-  toto.f5[Tata](new AnyRef{ type D = Tata; def m[E >: Null <: AnyRef](x: E): AnyRef = null; val x = tata })
+  //toto.f1[Tata](new Object{ type D = Tata; def m[E >: Null <: Object](x: Tata): Object = null; val x = tata })
+  //toto.f2[Tata](new Object{ type D = Tata; def m[E >: Null <: Object](x: Tata): Object = null; val x = tata })
+  //toto.f3[Tata](new Object{ type D = Tata; def m[E >: Null <: Object](x: Tata): Object = null; val x = tata })
+  //toto.f4[Tata](new Object{ type D = Tata; def m[E >: Null <: Object](x: D): Object = null; val x = tata })
+  toto.f5[Tata](new Object{ type D = Tata; def m[E >: Null <: Object](x: E): Object = null; val x: Test.Tata = tata })
 
-  toto.f6[Tata](new AnyRef{ type D = Tata; def m[E >: Null <: AnyRef](x: AnyRef): Tata = null })
-  toto.f7[Tata](new AnyRef{ type D = Tata; def m[E >: Null <: AnyRef](x: AnyRef): Tata = null })
-  toto.f8[Tata](new AnyRef{ type D = Tata; def m[E >: Null <: AnyRef](x: AnyRef): Tata = null })
-  toto.f9[Tata](new AnyRef{ type D = Tata; def m[E >: Null <: AnyRef](x: AnyRef): D = null })
-  toto.f0[Tata](new AnyRef{ type D = Tata; def m[E >: Null <: AnyRef](x: AnyRef): E = null })
+  toto.f6[Tata](new Object{ type D = Tata; def m[E >: Null <: Object](x: Object): Tata = null })
+  toto.f7[Tata](new Object{ type D = Tata; def m[E >: Null <: Object](x: Object): Tata = null })
+  toto.f8[Tata](new Object{ type D = Tata; def m[E >: Null <: Object](x: Object): Tata = null })
+  //toto.f9[Tata](new Object{ type D = Tata; def m[E >: Null <: Object](x: Object): D = null })
+  toto.f0[Tata](new Object{ type D = Tata; def m[E >: Null <: Object](x: Object): E = null })
 
   /* Bug #1246 */
   type Summable[T] = { def +(v : T) : T }
   def sum[T <: Summable[T]](xs : List[T]) = xs.reduceLeft[T](_ + _)
 
+  /* Bug #1004 & #967 */
+  type S1 = { def f(p: this.type): Unit }
+  val s1 = new { def f(p: this.type): Unit = () }
+
+  type S2 = { type T; def f(p: T): Unit }
+  //val s2: S2 = new { type T = A; def f(p: T): Unit = () }
+
+  def s3[U >: Null <: Object](p: { def f(p: U): Unit; def u: U }) = ()
+
 }