1 files changed, 42 insertions, 0 deletions
diff --git a/src/compiler/scala/tools/nsc/interpreter/ProductCompletion.scala b/src/compiler/scala/tools/nsc/interpreter/ProductCompletion.scala
new file mode 100644
index 0000000000..2aaa6114c2
--- /dev/null
+++ b/src/compiler/scala/tools/nsc/interpreter/ProductCompletion.scala
@@ -0,0 +1,42 @@
+/* NSC -- new Scala compiler
+ * Copyright 2005-2010 LAMP/EPFL
+ * @author Paul Phillips
+ */
+
+package scala.tools.nsc
+package interpreter
+
+class SeqCompletion[T](elems: Seq[T]) extends CompletionAware {
+  lazy val completions = elems.indices.toList map ("(%d)" format _)
+  private def elemAt(name: String) =
+    if (completions contains name) Some(elems(name drop 1 dropRight 1 toInt)) else None
+
+  override def execute(name: String) = elemAt(name)
+  override def follow(name: String) = elemAt(name) map (x => ProductCompletion(x))
+}
+
+/** TODO - deal with non-case products by giving them _1 _2 etc. */
+class ProductCompletion(root: Product) extends CompletionAware {
+  lazy val caseFields: List[Any] = root.productIterator.toList
+  lazy val caseNames: List[String] = ByteCode caseParamNamesForPath root.getClass.getName getOrElse Nil
+  private def isValid = caseFields.length == caseNames.length
+
+  private def fieldForName(s: String) = (completions indexOf s) match {
+    case idx if idx > -1 && isValid => Some(caseFields(idx))
+    case _                          => None
+  }
+
+  lazy val completions = caseNames
+  override def execute(name: String) = fieldForName(name)
+  override def follow(name: String) = fieldForName(name) map (x => ProductCompletion(x))
+}
+
+object ProductCompletion {
+  /** TODO: other traversables. */
+  def apply(elem: Any): CompletionAware = elem match {
+    case x: Seq[_]    => new SeqCompletion[Any](x)
+    case x: Product   => new ProductCompletion(x)
+    // case x: Map[_, _] =>
+    case _            => CompletionAware.Empty
+  }
+}