v0.2.48..v0.2.49 changeset MergeNearbyNodes.cpp

diff --git a/hoot-core/src/main/cpp/hoot/core/ops/MergeNearbyNodes.cpp b/hoot-core/src/main/cpp/hoot/core/ops/MergeNearbyNodes.cpp
index a3312a7..0082c42 100644
--- a/hoot-core/src/main/cpp/hoot/core/ops/MergeNearbyNodes.cpp
+++ b/hoot-core/src/main/cpp/hoot/core/ops/MergeNearbyNodes.cpp
@@ -69,6 +69,12 @@ MergeNearbyNodes::MergeNearbyNodes(Meters distance)
   if (_distance < 0.0)
   {
     _distance = ConfigOptions().getMergeNearbyNodesDistance();
+    if (_distance <= 0.0)
+    {
+      throw IllegalArgumentException(
+        "Nearby node merging distance must be greater than zero. Distance specified: " +
+        QString::number(_distance));
+    }
   }
 }