1 files changed, 12 insertions, 0 deletions
diff --git a/test/ruby/sentgen.rb b/test/ruby/sentgen.rb
index 94cffdad7a..49eae5c4ae 100644
--- a/test/ruby/sentgen.rb
+++ b/test/ruby/sentgen.rb
@@ -243,5 +243,17 @@ class SentGen
     end
     nil
   end
+
+  def SentGen.subst(obj, target, &b)
+    if obj.respond_to? :to_ary
+      a = []
+      obj.each {|e| a << subst(e, target, &b) }
+      a
+    elsif target === obj
+      yield obj
+    else
+      obj
+    end
+  end
 end