Fixed bug 592

1 files changed, 71 insertions, 0 deletions

diff --git a/test/files/pos/bug592.scala b/test/files/pos/bug592.scala
new file mode 100644
index 0000000000..4d41f112ee
--- /dev/null
+++ b/test/files/pos/bug592.scala
@@ -0,0 +1,71 @@
+trait Graph {
+  type Edge;
+  type Node <: NodeIntf;
+
+  trait NodeIntf {
+    def connectWith(node: Node): Edge;
+  }
+
+  def nodes: List[Node];
+  def edges: List[Edge];
+  def addNode: Node;
+
+  protected var ids = 0;
+}
+
+abstract class DirectedGraph extends Graph {
+  type Edge <: EdgeImpl;
+
+  class EdgeImpl(origin: Node, dest: Node) {
+    def from = origin;
+    def to = dest;
+    override def toString = ""+origin+" --> "+dest
+  }
+
+  class NodeImpl requires Node extends NodeIntf {
+    val id = ids
+    ids = ids + 1
+    def connectWith(node: Node): Edge = {
+      val edge = newEdge(this, node);
+      edges = edge :: edges;
+      edge;
+    }
+    override def toString = "Node "+id
+  }
+
+  protected def newNode: Node;
+  protected def newEdge(from: Node, to: Node): Edge;
+  var nodes: List[Node] = Nil;
+  var edges: List[Edge] = Nil;
+
+  def addNode: Node = {
+    val node = newNode;
+    nodes = node :: nodes;
+    node;
+  }
+}
+
+class ConcreteDirectedGraph extends DirectedGraph {
+  type Edge = EdgeImpl;
+  type Node = NodeImpl;
+
+  protected def newNode: Node = {
+    new NodeImpl;
+  }
+
+  protected def newEdge(f: Node, t: Node): Edge = {
+    new EdgeImpl(f, t);
+  }
+}
+
+object ExplicitThis {
+  def main(args: Array[String]): Unit = {
+    val g: Graph = new ConcreteDirectedGraph;
+    val n1 = g.addNode;
+    val n2 = g.addNode;
+    val n3 = g.addNode;
+    Console.println(n1.connectWith(n2))
+    Console.println(n2.connectWith(n3))
+    Console.println(n1.connectWith(n3))
+  }
+}