1 files changed, 14 insertions, 2 deletions
diff --git a/src/compiler/scala/tools/nsc/ast/TreeBrowsers.scala b/src/compiler/scala/tools/nsc/ast/TreeBrowsers.scala
index 613928856d..37dea497fc 100644
--- a/src/compiler/scala/tools/nsc/ast/TreeBrowsers.scala
+++ b/src/compiler/scala/tools/nsc/ast/TreeBrowsers.scala
@@ -36,13 +36,19 @@ abstract class TreeBrowsers {
 
   def create(): SwingBrowser = new SwingBrowser();
 
+  trait ValidTree extends Tree {
+    protected def initErrorCheck {
+      hasErrorTree = Some(false)
+    }
+  }
+
   /** Pseudo tree class, so that all JTree nodes are treated uniformly */
-  case class ProgramTree(units: List[UnitTree]) extends Tree {
+  case class ProgramTree(units: List[UnitTree]) extends ValidTree {
     override def toString(): String = "Program"
   }
 
   /** Pseudo tree class, so that all JTree nodes are treated uniformly */
-  case class UnitTree(unit: CompilationUnit) extends Tree {
+  case class UnitTree(unit: CompilationUnit) extends ValidTree {
     override def toString(): String = unit.toString()
   }
 
@@ -490,6 +496,9 @@ abstract class TreeBrowsers {
 
       case Star(t) =>
         ("Star", EMPTY)
+
+      case _: AbsErrorTree =>
+        ("ErrorTree", EMPTY)
     }
 
     /** Return a list of children for the given tree node */
@@ -631,6 +640,9 @@ abstract class TreeBrowsers {
 
       case Star(t) =>
         List(t)
+
+      case _: AbsErrorTree =>
+        Nil
     }
 
     /** Return a textual representation of this t's symbol */