Fix/#329 and others

src/dotty/tools/dotc/ast/tpd.scala

@@ -759,6 +759,14 @@ object tpd extends Trees.Instance[Type] with TypedTreeInfo {
     Ident(defn.ScalaRuntimeModule.requiredMethod(name).termRef).appliedToArgs(args)
   }
 
+  /** An extractor that pulls out type arguments */
+  object MaybePoly {
+    def unapply(tree: Tree): Option[(Tree, List[Tree])] = tree match {
+      case TypeApply(tree, targs) => Some(tree, targs)
+      case _ => Some(tree, Nil)
+    }
+  }
+
   /** A traverser that passes the enlcosing class or method as an argumenr
    *  to the traverse method.
    */

src/dotty/tools/dotc/core/TypeApplications.scala

@@ -285,7 +285,7 @@ class TypeApplications(val self: Type) extends AnyVal {
    */
   def underlyingIfRepeated(isJava: Boolean)(implicit ctx: Context): Type =
     if (self.isRepeatedParam) {
-      val seqClass = if(isJava) defn.ArrayClass else defn.SeqClass
+      val seqClass = if (isJava) defn.ArrayClass else defn.SeqClass
       translateParameterized(defn.RepeatedParamClass, seqClass)
     }
     else self

src/dotty/tools/dotc/core/TypeComparer.scala

@@ -648,45 +648,34 @@ class TypeComparer(initctx: Context) extends DotClass with ConstraintHandling wi
   // Tests around `matches`
 
   /** A function implementing `tp1` matches `tp2`. */
-  final def matchesType(tp1: Type, tp2: Type, alwaysMatchSimple: Boolean): Boolean = tp1 match {
+  final def matchesType(tp1: Type, tp2: Type, relaxed: Boolean): Boolean = tp1.widen match {
     case tp1: MethodType =>
-      tp2 match {
+      tp2.widen match {
         case tp2: MethodType =>
           tp1.isImplicit == tp2.isImplicit &&
             matchingParams(tp1.paramTypes, tp2.paramTypes, tp1.isJava, tp2.isJava) &&
-            matchesType(tp1.resultType, tp2.resultType.subst(tp2, tp1), alwaysMatchSimple)
-        case tp2: ExprType =>
-          tp1.paramNames.isEmpty &&
-            matchesType(tp1.resultType, tp2.resultType, alwaysMatchSimple)
-        case _ =>
-          false
-      }
-    case tp1: ExprType =>
-      tp2 match {
-        case tp2: MethodType =>
-          tp2.paramNames.isEmpty &&
-            matchesType(tp1.resultType, tp2.resultType, alwaysMatchSimple)
-        case tp2: ExprType =>
-          matchesType(tp1.resultType, tp2.resultType, alwaysMatchSimple)
-        case _ =>
-          false // was: matchesType(tp1.resultType, tp2, alwaysMatchSimple)
+            matchesType(tp1.resultType, tp2.resultType.subst(tp2, tp1), relaxed)
+        case tp2 =>
+          relaxed && tp1.paramNames.isEmpty &&
+            matchesType(tp1.resultType, tp2, relaxed)
       }
     case tp1: PolyType =>
-      tp2 match {
+      tp2.widen match {
         case tp2: PolyType =>
           sameLength(tp1.paramNames, tp2.paramNames) &&
-            matchesType(tp1.resultType, tp2.resultType.subst(tp2, tp1), alwaysMatchSimple)
+            matchesType(tp1.resultType, tp2.resultType.subst(tp2, tp1), relaxed)
         case _ =>
           false
       }
     case _ =>
-      tp2 match {
-        case _: MethodType | _: PolyType =>
+      tp2.widen match {
+        case _: PolyType =>
           false
-        case tp2: ExprType =>
-          false // was: matchesType(tp1, tp2.resultType, alwaysMatchSimple)
-        case _ =>
-          alwaysMatchSimple || isSameType(tp1, tp2)
+        case tp2: MethodType =>
+          relaxed && tp2.paramNames.isEmpty && 
+            matchesType(tp1, tp2.resultType, relaxed)
+        case tp2 =>
+          relaxed || isSameType(tp1, tp2)
       }
   }
 

src/dotty/tools/dotc/core/Types.scala

@@ -598,17 +598,21 @@ object Types {
      *    - Either both types are polytypes with the same number of
      *      type parameters and their result types match after renaming
      *      corresponding type parameters
-     *    - Or both types are (possibly nullary) method types with equivalent parameter types
-     *      and matching result types
-     *    - Or both types are equivalent
-     *    - Or phase.erasedTypes is false and both types are neither method nor
-     *      poly types.
+     *    - Or both types are method types with =:=-equivalent(*) parameter types
+     *      and matching result types after renaming corresponding parameter types
+     *      if the method types are dependent.
+     *    - Or both types are =:=-equivalent
+     *    - Or phase.erasedTypes is false, and neither type takes 
+     *      term or type parameters.
+     *      
+     *  (*) when matching with a Java method, we also regard Any and Object as equivalent
+     *      parameter types.
      */
     def matches(that: Type)(implicit ctx: Context): Boolean =
       if (Config.newMatch) this.signature matches that.signature
       else track("matches") {
         ctx.typeComparer.matchesType(
-          this, that, alwaysMatchSimple = !ctx.phase.erasedTypes)
+          this, that, relaxed = !ctx.phase.erasedTypes)
       }
 
     /** This is the same as `matches` except that it also matches => T with T and

src/dotty/tools/dotc/transform/OverridingPairs.scala

@@ -39,12 +39,7 @@ object OverridingPairs {
      *  relative to <base>.this do
      */
     protected def matches(sym1: Symbol, sym2: Symbol): Boolean =
-      sym1.isType || {
-        val info1 = self.memberInfo(sym1)
-        val info2 = self.memberInfo(sym2)
-        // info1.signature == info2.signature &&  // TODO enable for speed
-        info1 matches info2
-      }
+      sym1.isType || self.memberInfo(sym1).matches(self.memberInfo(sym2))
 
     /** The symbols that can take part in an overriding pair */
     private val decls = {

src/dotty/tools/dotc/typer/EtaExpansion.scala

@@ -34,8 +34,11 @@ object EtaExpansion {
    *     lhs += expr
    */
   def liftAssigned(defs: mutable.ListBuffer[Tree], tree: Tree)(implicit ctx: Context): Tree = tree match {
-    case Apply(fn @ Select(pre, name), args) =>
-      cpy.Apply(tree)(cpy.Select(fn)(lift(defs, pre), name), liftArgs(defs, fn.tpe, args))
+    case Apply(MaybePoly(fn @ Select(pre, name), targs), args) =>
+      cpy.Apply(tree)(
+        cpy.Select(fn)(
+          lift(defs, pre), name).appliedToTypeTrees(targs), 
+          liftArgs(defs, fn.tpe, args))
     case Select(pre, name) =>
       cpy.Select(tree)(lift(defs, pre), name)
     case _ =>

src/dotty/tools/dotc/typer/Typer.scala

@@ -400,10 +400,13 @@ class Typer extends Namer with TypeAssigner with Applications with Implicits wit
     tree.lhs match {
       case lhs @ Apply(fn, args) =>
         typed(cpy.Apply(lhs)(untpd.Select(fn, nme.update), args :+ tree.rhs), pt)
-      case untpd.TypedSplice(Apply(Select(fn, app), args)) if app == nme.apply =>
-        typed(cpy.Apply(fn)(
-            untpd.Select(untpd.TypedSplice(fn), nme.update),
-            (args map untpd.TypedSplice) :+ tree.rhs), pt)
+      case untpd.TypedSplice(Apply(MaybePoly(Select(fn, app), targs), args)) if app == nme.apply =>
+        val rawUpdate: untpd.Tree = untpd.Select(untpd.TypedSplice(fn), nme.update)
+        val wrappedUpdate = 
+          if (targs.isEmpty) rawUpdate 
+          else untpd.TypeApply(rawUpdate, targs map untpd.TypedSplice)
+        val appliedUpdate = cpy.Apply(fn)(wrappedUpdate, (args map untpd.TypedSplice) :+ tree.rhs)
+        typed(appliedUpdate, pt)
       case lhs =>
         val lhsCore = typedUnadapted(lhs)
         def lhs1 = typed(untpd.TypedSplice(lhsCore))

test/dotc/tests.scala

@@ -82,8 +82,8 @@ class tests extends CompilerTest {
   @Test def neg_autoTupling = compileFile(posDir, "autoTuplingTest", "-language:noAutoTupling" :: Nil, xerrors = 4)
   @Test def neg_autoTupling2 = compileFile(negDir, "autoTuplingTest", xerrors = 4)
   @Test def neg_companions = compileFile(negDir, "companions", xerrors = 1)
-  @Test def neg_over = compileFile(negDir, "over", xerrors = 1)
-  @Test def neg_overrides = compileFile(negDir, "overrides", xerrors = 7)
+  @Test def neg_over = compileFile(negDir, "over", xerrors = 3)
+  @Test def neg_overrides = compileFile(negDir, "overrides", xerrors = 11)
   @Test def neg_projections = compileFile(negDir, "projections", xerrors = 1)
   @Test def neg_i39 = compileFile(negDir, "i39", xerrors = 1)
   @Test def neg_i50_volatile = compileFile(negDir, "i50-volatile", xerrors = 4)

tests/pending/pos/t3363-new.scala → tests/disabled/structural-type/pos/t3363-new.scala

@@ -7,7 +7,7 @@ object TestCase {
 
         //if fs was reduced to List (generic type with one parameter) then the code compiles
         //if you inherit from MapOps[T] instead of MapOps[F] then code compiles fine
-        implicit def map2ops[T,F](fs: Map[T,F]): TestCase.MapOps[F]{lazy val m: reflect.runtime.universe.TypeTag[T]; def is(xs: List[T]): List[List[T]]} = new MapOps[F] {
+        implicit def map2ops[T,F](fs: Map[T,F]): TestCase.MapOps[F]{val m: reflect.runtime.universe.TypeTag[T]; def is(xs: List[T]): List[List[T]]} = new MapOps[F] {
           //if you remove this line, then code compiles
       lazy val m: TypeTag[T] = sys.error("just something to make it compile")
       def is(xs: List[T]) = List(xs)

tests/pending/pos/t3363-old.scala → tests/disabled/structural-type/pos/t3363-old.scala

@@ -5,7 +5,7 @@ object TestCase {
 
         //if fs was reduced to List (generic type with one parameter) then the code compiles
         //if you inherit from MapOps[T] instead of MapOps[F] then code compiles fine
-        implicit def map2ops[T,F](fs: Map[T,F]): TestCase.MapOps[F]{lazy val m: Manifest[T]; def is(xs: List[T]): List[List[T]]} = new MapOps[F] {
+        implicit def map2ops[T,F](fs: Map[T,F]): TestCase.MapOps[F]{val m: Manifest[T]; def is(xs: List[T]): List[List[T]]} = new MapOps[F] {
           //if you remove this line, then code compiles
 	    lazy val m: Manifest[T] = sys.error("just something to make it compile")
 	    def is(xs: List[T]) = List(xs)

tests/neg/over.scala

@@ -8,3 +8,11 @@ class C extends T {
   override val y = 2
 
 }
+
+class D extends T {
+
+  def x(): String = ""
+
+}
+
+

tests/neg/overrides.scala

@@ -79,3 +79,45 @@ class Y2 extends X2 {
 class X3 {
   override type T = A1
 }
+
+package p3 {
+
+// Dotty change of rules: Toverrider#f does not
+// override TCommon#f, hence the accidental override rule
+// applies.
+trait TCommon {
+  def f: String
+}
+
+class C1 extends TCommon {
+  def f = "in C1"
+}
+
+trait TOverrider { this: TCommon =>
+  override def f = "in TOverrider"   // The overridden self-type member...
+}
+
+class C2 extends C1 with TOverrider  // ... fails to override, here.
+
+}
+
+package p4 {
+
+  abstract class C[T] { def head: T }
+  case class D[T](head: Int) extends C[T]
+
+}
+
+package p5 {
+class A {
+  def m: String = "foo"
+}
+
+class B extends A {
+  override val m: Int = 42
+}
+
+class C extends A {
+  override def m: Int = 42
+}
+}

tests/pending/pos/java-override/A.java

@@ -0,0 +1,3 @@
+public interface A {
+    void o(Object o);
+}

tests/pending/pos/java-override/B.scala

@@ -0,0 +1,7 @@
+//trait T { def t(o: Object): Unit }
+
+class B extends A /*with T*/ {
+  override def o(o: Any): Unit = ()
+
+  //override def t(o: AnyRef): Unit = ()
+}

tests/pending/pos/t3480.scala

@@ -1,4 +1,4 @@
 object Test {
-  val List(_*) = List(1)
+  val List(_: _*) = List(1)
 	val Array( who, what : _* ) = "Eclipse plugin cannot not handle this" split (" ")
 }

tests/pending/pos/scoping1.scala → tests/pos/scoping1.scala

@@ -2,7 +2,7 @@ object This extends App {
   trait A {
     def foo(): Unit
   }
-  class C { self: A =>
+ abstract class C { self: A =>
     def bar() = this.foo()
   }
   class D extends C with A {

tests/pos/subtyping.scala

@@ -1,32 +1,5 @@
-class A {
-  def test1(): Unit = {
-    implicitly[this.type <:< this.type]
-    implicitly[this.type <:< A]
-  }
-}
 object test {
 
-  def tag1[T](x: T): String & T = ???
-  def tag2[T](x: T): T & String = ???
-
-  val x1: Int & String = tag1(0)
-  val x2: Int & String = tag2(0)
-  val x3: String & Int = tag1(0)
-  val x4: String & Int = tag2(0)
-
-}
-
-object test2 {
-
-  class A
-  class B
-
-  val x: A | B = ???
-  val y: B | A = x
-
-  val a: A & B = ???
-  val b: B & A = a
+  val x: Int = 1
 
 }
-
-

tests/pending/pos/t319.scala → tests/pos/t319.scala

@@ -14,7 +14,8 @@ object test {
   val a = new  A { type T = String };
   /** val b: B { type T = String } = functor(a) */
   val b: B { type T = String } = {
-    val tmp = new functor() { val arg = a };
+    val tmp = new functor() { val arg: A { type T = String } = a };
+      // Dotty deviaton: arg needs an explicit type here, or else the inherited type `A` would be assumed.
     tmp.res
   }
 

tests/pos/t3278.scala

@@ -0,0 +1,30 @@
+class Foo
+class Test {
+	def update[B](x : B, b : Int): Unit = {}
+	def apply[B](x : B) = 1
+}
+class Test2 {
+  type B = Foo
+	def update(x : B, b : Int): Unit = {}
+	def apply(x : B) = 1
+}
+
+object Test {
+	def main(a : Array[String]): Unit = {
+		val a = new Test
+		val f = new Foo
+		a(f) = 1 //works
+		a(f) = a(f) + 1 //works
+		a(f) += 1 //error: reassignment to val
+	}
+}
+object Test2 {
+	def main(args : Array[String]): Unit = {
+                args(0) += "a"
+		val a = new Test2
+		val f = new Foo
+		a(f) = 1 //works
+		a(f) = a(f) + 1 //works
+		a(f) += 1 //error: reassignment to val
+	}
+}