Add () for nullary method applications

Fix errors everywhere where a nullary method is called
without a () argument.

Author: odersky

.gitignore

@@ -70,3 +70,4 @@ compiler/test/debug/Gen.jar
 
 compiler/before-pickling.txt
 compiler/after-pickling.txt
+*.dotty-ide-version

collection-strawman

@@ -69,7 +69,7 @@ object desugar {
         val originalOwner = sym.owner
         def apply(tp: Type) = tp match {
           case tp: NamedType if tp.symbol.exists && (tp.symbol.owner eq originalOwner) =>
-            val defctx = ctx.outersIterator.dropWhile(_.scope eq ctx.scope).next
+            val defctx = ctx.outersIterator.dropWhile(_.scope eq ctx.scope).next()
             var local = defctx.denotNamed(tp.name).suchThat(_ is ParamOrAccessor).symbol
             if (local.exists) (defctx.owner.thisType select local).dealias
             else {
@@ -538,12 +538,12 @@ object desugar {
     val cdef1 = addEnumFlags {
       val originalTparamsIt = originalTparams.toIterator
       val originalVparamsIt = originalVparamss.toIterator.flatten
-      val tparamAccessors = derivedTparams.map(_.withMods(originalTparamsIt.next.mods))
+      val tparamAccessors = derivedTparams.map(_.withMods(originalTparamsIt.next().mods))
       val caseAccessor = if (isCaseClass) CaseAccessor else EmptyFlags
       val vparamAccessors = derivedVparamss match {
         case first :: rest =>
-          first.map(_.withMods(originalVparamsIt.next.mods | caseAccessor)) ++
-          rest.flatten.map(_.withMods(originalVparamsIt.next.mods))
+          first.map(_.withMods(originalVparamsIt.next().mods | caseAccessor)) ++
+          rest.flatten.map(_.withMods(originalVparamsIt.next().mods))
         case _ =>
           Nil
       }

compiler/src/dotty/tools/dotc/ast/Desugar.scala

@@ -70,7 +70,7 @@ object NavigateAST {
   def pathTo(pos: Position, from: Positioned, skipZeroExtent: Boolean = false)(implicit ctx: Context): List[Positioned] = {
     def childPath(it: Iterator[Any], path: List[Positioned]): List[Positioned] = {
       while (it.hasNext) {
-        val path1 = it.next match {
+        val path1 = it.next() match {
           case p: Positioned => singlePath(p, path)
           case xs: List[_] => childPath(xs.iterator, path)
           case _ => path

compiler/src/dotty/tools/dotc/ast/NavigateAST.scala

@@ -53,7 +53,7 @@ trait TreeInfo[T >: Untyped <: Type] { self: Trees.Instance[T] =>
     def map[R](f: (Symbol, Tree) => R): List[R] = {
       val b = List.newBuilder[R]
       foreach(b += f(_, _))
-      b.result
+      b.result()
     }
   }
 

compiler/src/dotty/tools/dotc/ast/TreeInfo.scala

@@ -129,7 +129,7 @@ object Trees {
     private def checkChildrenTyped(it: Iterator[Any])(implicit ctx: Context): Unit =
       if (!this.isInstanceOf[Import[_]])
         while (it.hasNext)
-          it.next match {
+          it.next() match {
             case x: Ident[_] => // untyped idents are used in a number of places in typed trees
             case x: Tree[_] =>
               assert(x.hasType || ctx.reporter.errorsReported,

compiler/src/dotty/tools/dotc/ast/Trees.scala

@@ -348,15 +348,15 @@ object Contexts {
      */
     def thisCallArgContext: Context = {
       assert(owner.isClassConstructor)
-      val constrCtx = outersIterator.dropWhile(_.outer.owner == owner).next
+      val constrCtx = outersIterator.dropWhile(_.outer.owner == owner).next()
       superOrThisCallContext(owner, constrCtx.scope)
         .setTyperState(typerState)
         .setGadt(gadt)
     }
 
     /** The super- or this-call context with given owner and locals. */
     private def superOrThisCallContext(owner: Symbol, locals: Scope): FreshContext = {
-      var classCtx = outersIterator.dropWhile(!_.isClassDefContext).next
+      var classCtx = outersIterator.dropWhile(!_.isClassDefContext).next()
       classCtx.outer.fresh.setOwner(owner)
         .setScope(locals)
         .setMode(classCtx.mode | Mode.InSuperCall)

compiler/src/dotty/tools/dotc/core/Contexts.scala

@@ -37,7 +37,7 @@ object Decorators {
   implicit class SymbolIteratorDecorator(val it: Iterator[Symbol]) extends AnyVal {
     final def findSymbol(p: Symbol => Boolean): Symbol = {
       while (it.hasNext) {
-        val sym = it.next
+        val sym = it.next()
         if (p(sym)) return sym
       }
       NoSymbol

compiler/src/dotty/tools/dotc/core/Decorators.scala

@@ -512,7 +512,7 @@ object Denotations {
                 def lubSym(overrides: Iterator[Symbol], previous: Symbol): Symbol =
                   if (!overrides.hasNext) previous
                   else {
-                    val candidate = overrides.next
+                    val candidate = overrides.next()
                     if (owner2 derivesFrom candidate.owner)
                       if (candidate isAccessibleFrom pre) candidate
                       else lubSym(overrides, previous orElse candidate)
@@ -779,7 +779,7 @@ object Denotations {
       }
 
       if (valid.runId != currentPeriod.runId)
-        if (exists) initial.bringForward.current
+        if (exists) initial.bringForward().current
         else this
       else {
         var cur = this

compiler/src/dotty/tools/dotc/core/Denotations.scala

@@ -28,7 +28,7 @@ trait Phases {
     if ((this eq NoContext) || !phase.exists) Nil
     else {
       val rest = outersIterator.dropWhile(_.phase == phase)
-      phase :: (if (rest.hasNext) rest.next.phasesStack else Nil)
+      phase :: (if (rest.hasNext) rest.next().phasesStack else Nil)
     }
 
   /** Execute `op` at given phase */