Fix ()'s in new/exploreTyperState

Author: odersky

compiler/src/dotty/tools/dotc/typer/Implicits.scala

@@ -507,7 +507,7 @@ trait Implicits { self: Typer =>
     && from.isValueType
     && (  from.isValueSubType(to)
        || inferView(dummyTreeOfType(from), to)
-            (ctx.fresh.addMode(Mode.ImplicitExploration).setExploreTyperState)
+            (ctx.fresh.addMode(Mode.ImplicitExploration).setExploreTyperState())
             .isInstanceOf[SearchSuccess]
           // TODO: investigate why we can't TyperState#test here
        )
@@ -787,7 +787,7 @@ trait Implicits { self: Typer =>
         val generated1 = adapt(generated, pt)
         lazy val shadowing =
           typed(untpd.Ident(ref.name) withPos pos.toSynthetic, funProto)(
-            nestedContext.addMode(Mode.ImplicitShadowing).setExploreTyperState)
+            nestedContext.addMode(Mode.ImplicitShadowing).setExploreTyperState())
         def refSameAs(shadowing: Tree): Boolean =
           ref.symbol == closureBody(shadowing).symbol || {
             shadowing match {
@@ -819,7 +819,7 @@ trait Implicits { self: Typer =>
           val history = ctx.searchHistory nest wildProto
           val result =
             if (history eq ctx.searchHistory) divergingImplicit(cand.ref)
-            else typedImplicit(cand)(nestedContext.setNewTyperState.setSearchHistory(history))
+            else typedImplicit(cand)(nestedContext.setNewTyperState().setSearchHistory(history))
           result match {
             case fail: SearchFailure =>
               rankImplicits(pending1, acc)

compiler/src/dotty/tools/dotc/typer/ProtoTypes.scala

@@ -39,11 +39,9 @@ object ProtoTypes {
       (tp.widenExpr relaxed_<:< pt.widenExpr) || viewExists(tp, pt)
 
     /** Test compatibility after normalization in a fresh typerstate. */
-    def normalizedCompatible(tp: Type, pt: Type)(implicit ctx: Context) = {
-      val nestedCtx = ctx.fresh.setExploreTyperState
-      val normTp = normalize(tp, pt)(nestedCtx)
-      isCompatible(normTp, pt)(nestedCtx) ||
-        pt.isRef(defn.UnitClass) && normTp.isParameterless
+    def normalizedCompatible(tp: Type, pt: Type)(implicit ctx: Context) = ctx.typerState.test {
+      val normTp = normalize(tp, pt)
+      isCompatible(normTp, pt) || pt.isRef(defn.UnitClass) && normTp.isParameterless
     }
 
     private def disregardProto(pt: Type)(implicit ctx: Context): Boolean = pt.dealias match {

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

@@ -1751,7 +1751,7 @@ class Typer extends Namer with TypeAssigner with Applications with Implicits wit
     typed(tree, selType)(ctx addMode Mode.Pattern)
 
   def tryEither[T](op: Context => T)(fallBack: (T, TyperState) => T)(implicit ctx: Context) = {
-    val nestedCtx = ctx.fresh.setNewTyperState
+    val nestedCtx = ctx.fresh.setNewTyperState()
     val result = op(nestedCtx)
     if (nestedCtx.reporter.hasErrors)
       fallBack(result, nestedCtx.typerState)