2 files changed, 26 insertions, 0 deletions
diff --git a/lib/leap_cli/config/node.rb b/lib/leap_cli/config/node.rb
index 5b911bf..740f9bb 100644
--- a/lib/leap_cli/config/node.rb
+++ b/lib/leap_cli/config/node.rb
@@ -32,6 +32,14 @@ module LeapCli; module Config
       end
       return vagrant_range.include?(ip_address)
     end
+
+    #
+    # can be overridden by the platform.
+    # returns a list of node names that should be tested before this node
+    #
+    def test_dependencies
+      []
+    end
   end
 
 end; end
diff --git a/lib/leap_cli/config/object_list.rb b/lib/leap_cli/config/object_list.rb
index 9ca4697..910e2f7 100644
--- a/lib/leap_cli/config/object_list.rb
+++ b/lib/leap_cli/config/object_list.rb
@@ -1,9 +1,12 @@
+require 'tsort'
+
 module LeapCli
   module Config
     #
     # A list of Config::Object instances (internally stored as a hash)
     #
     class ObjectList < Hash
+      include TSort
 
       def initialize(config=nil)
         if config
@@ -171,6 +174,21 @@ module LeapCli
         end
       end
 
+      #
+      # topographical sort based on test dependency
+      #
+      def tsort_each_node(&block)
+        self.each_key(&block)
+      end
+
+      def tsort_each_child(node_name, &block)
+        self[node_name].test_dependencies.each(&block)
+      end
+
+      def names_in_test_dependency_order
+        self.tsort
+      end
+
     end
   end
 end