Refactor decomposeProtoFunction

Author: nicolasstucki

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

@@ -1321,18 +1321,18 @@ class Typer(@constructorOnly nestingLevel: Int = 0) extends Namer
       case tp: TypeParamRef =>
         decomposeProtoFunction(ctx.typerState.constraint.entry(tp).bounds.hi, defaultArity, pos)
       case _ => pt1.findFunctionType match {
-        case ft @ defn.PolyFunctionOf(mt @ MethodTpe(_, formals, restpe)) =>
-          if formals.length != defaultArity then fallbackProto
-          else (formals, untpd.InLambdaTypeTree(isResult = true, (_, syms) => restpe.substParams(mt, syms.map(_.termRef))))
-        case ft @ defn.DependentFunctionRefinementOf(_, mt @ MethodTpe(_, formals, restpe)) =>
-          if formals.length != defaultArity then fallbackProto
-          else (formals, untpd.InLambdaTypeTree(isResult = true, (_, syms) => restpe.substParams(mt, syms.map(_.termRef))))
         case ft @ defn.FunctionNOf(_, _, _) =>
           // if expected parameter type(s) are wildcards, approximate from below.
           // if expected result type is a wildcard, approximate from above.
           // this can type the greatest set of admissible closures.
 
           (ft.argInfos.init, typeTree(interpolateWildcards(ft.argInfos.last.hiBound)))
+        case ft @ defn.PolyFunctionOf(mt @ MethodTpe(_, formals, restpe)) =>
+          if formals.length != defaultArity then fallbackProto
+          else (formals, untpd.InLambdaTypeTree(isResult = true, (_, syms) => restpe.substParams(mt, syms.map(_.termRef))))
+        case ft @ defn.DependentFunctionRefinementOf(_, mt @ MethodTpe(_, formals, restpe)) =>
+          if formals.length != defaultArity then fallbackProto
+          else (formals, untpd.InLambdaTypeTree(isResult = true, (_, syms) => restpe.substParams(mt, syms.map(_.termRef))))
         case SAMType(mt @ MethodTpe(_, formals, _), samParent) =>
           val restpe = mt.resultType match
             case mt: MethodType => mt.toFunctionType(isJava = samParent.classSymbol.is(JavaDefined))