T1002281 class cast ex

org.scala-refactoring.library/src/main/scala/scala/tools/refactoring/common/Selections.scala

@@ -5,10 +5,9 @@
 package scala.tools.refactoring
 package common
 
-import collection.mutable.ListBuffer
-import tools.nsc.Global
+import scala.collection.mutable.ListBuffer
+import scala.reflect.internal.util.OffsetPosition
 import scala.reflect.internal.util.RangePosition
-import scala.reflect.internal.Flags
 
 trait Selections extends TreeTraverser with common.PimpedTrees {
 
@@ -73,12 +72,12 @@ trait Selections extends TreeTraverser with common.PimpedTrees {
     /**
      * Returns true if the given Tree is fully contained in the selection.
      */
-    def contains(t: Tree) = isPosContainedIn(t.pos, pos)
+    def contains(t: Tree): Boolean = isPosContainedIn(t.pos, pos)
 
     /**
      * Returns true if the given Tree fully contains this selection.
      */
-    def isContainedIn(t: Tree) = isPosContainedIn(pos, t.pos)
+    def isContainedIn(t: Tree): Boolean = isPosContainedIn(pos, t.pos)
 
     /**
      * Tries to find the selected SymTree: first it is checked if the selection
@@ -233,7 +232,7 @@ trait Selections extends TreeTraverser with common.PimpedTrees {
 
       // some trees have to be selected as a whole if more than one child
       // is selected. For example if a method parameter and the body is selected,
-      // we select the DefDef as a whole to get a complete selection. 
+      // we select the DefDef as a whole to get a complete selection.
       def expandToParentIfRequired(s: Selection) =
         s.enclosingTree match {
           case t @ (_: DefDef | _: Function | _: If | _: Match | _: Try | _: CaseDef) =>
@@ -276,12 +275,21 @@ trait Selections extends TreeTraverser with common.PimpedTrees {
       else
         None
 
+    /**
+     * An [[scala.reflect.internal.util.OffsetPosition]] is needed as a new
+     * position. Throws an exception if another position type is passed.
+     */
     def withPos(newPos: Position): Selection = {
+      val p = newPos match {
+        case p: RangePosition  => p
+        case p: OffsetPosition => new RangePosition(p.source, p.start, p.start, p.start)
+        case p                 => throw new IllegalArgumentException(s"An offset position is required, but was: $p")
+      }
       val outer = this
       new Selection {
-        val root = outer.root
-        val file = outer.file
-        val pos = newPos.asInstanceOf[RangePosition]
+        override val root = outer.root
+        override val file = outer.file
+        override val pos = p
       }
     }
 
@@ -388,36 +396,36 @@ trait Selections extends TreeTraverser with common.PimpedTrees {
     }
   }
 
-  def skipForExpressionTrees(t: Tree) = t match {
+  def skipForExpressionTrees(t: Tree): Tree = t match {
     case t @ TypeApply(fun: Select, args) if fun.pos.eq(t.pos) && fun.pos.eq(fun.qualifier.pos) =>
       fun.qualifier
     case t @ Select(qualifier, nme) if t.pos.eq(qualifier.pos) && nme.toTermName.toString == "withFilter" =>
       qualifier
     case t => t
   }
 
-  case class FileSelection(file: tools.nsc.io.AbstractFile, root: Tree, from: Int, to: Int) extends Selection {
+  case class FileSelection(override val file: tools.nsc.io.AbstractFile, override val root: Tree, from: Int, to: Int) extends Selection {
 
     @deprecated("Please use the primary constructor.", "0.4.0")
     def this(file: tools.nsc.io.AbstractFile, from: Int, to: Int) = {
       this(file, compilationUnitOfFile(file).get.body, from, to)
     }
 
-    lazy val pos = new RangePosition(root.pos.source, from, from, to)
+    override lazy val pos = new RangePosition(root.pos.source, from, from, to)
   }
 
   object FileSelection {
     @deprecated("Please use the primary constructor.", "0.4.0")
-    def apply(file: tools.nsc.io.AbstractFile, from: Int, to: Int) = new FileSelection(file: tools.nsc.io.AbstractFile, from: Int, to: Int)
+    def apply(file: tools.nsc.io.AbstractFile, from: Int, to: Int): FileSelection = new FileSelection(file: tools.nsc.io.AbstractFile, from: Int, to: Int)
   }
 
-  case class TreeSelection(root: Tree) extends Selection {
+  case class TreeSelection(override val root: Tree) extends Selection {
 
     if (!root.pos.isRange)
       error("Position not a range.")
 
-    val pos = root.pos.asInstanceOf[RangePosition]
+    override val pos: RangePosition = root.pos.asInstanceOf[RangePosition]
 
-    val file = pos.source.file
+    override val file: tools.nsc.io.AbstractFile = pos.source.file
   }
 }