check for null repository config (fix for FELIX-2187)


git-svn-id: https://svn.apache.org/repos/asf/felix/trunk@921392 13f79535-47bb-0310-9956-ffa450edef68
diff --git a/sigil/eclipse/core/src/org/apache/felix/sigil/eclipse/internal/repository/eclipse/SigilRepositoryManager.java b/sigil/eclipse/core/src/org/apache/felix/sigil/eclipse/internal/repository/eclipse/SigilRepositoryManager.java
index 3116b2c..da09428 100644
--- a/sigil/eclipse/core/src/org/apache/felix/sigil/eclipse/internal/repository/eclipse/SigilRepositoryManager.java
+++ b/sigil/eclipse/core/src/org/apache/felix/sigil/eclipse/internal/repository/eclipse/SigilRepositoryManager.java
@@ -156,7 +156,13 @@
         else
         {
             IRepositorySet set = SigilCore.getRepositoryConfiguration().getRepositorySet( repositorySet );
-            return set.getRepositories();
+            if ( set == null ) {
+                SigilCore.error( "Unknown repository set " + repositorySet );
+                return SigilCore.getRepositoryConfiguration().getDefaultRepositorySet().getRepositories();
+            }
+            else {
+                return set.getRepositories();
+            }
         }
     }