1 files changed, 25 insertions, 0 deletions
diff --git a/googletest/include/gtest/internal/gtest-internal.h b/googletest/include/gtest/internal/gtest-internal.h
index 72d83f0..2a6e4da 100644
--- a/googletest/include/gtest/internal/gtest-internal.h
+++ b/googletest/include/gtest/internal/gtest-internal.h
@@ -940,6 +940,31 @@ typedef char IsNotContainer;
 template <class C>
 IsNotContainer IsContainerTest(long /* dummy */) { return '\0'; }
 
+template <typename C, bool = 
+  sizeof(IsContainerTest<C>(0)) == sizeof(IsContainer)
+>
+struct IsRecursiveContainerImpl;
+
+template <typename C>
+struct IsRecursiveContainerImpl<C, false> : public false_type {};
+
+template <typename C>
+struct IsRecursiveContainerImpl<C, true> {
+  typedef
+    typename IteratorTraits<typename C::iterator>::value_type
+  value_type;
+  typedef is_same<value_type, C> type;
+};
+
+// IsRecursiveContainer<Type> is a unary compile-time predicate that
+// evaluates whether C is a recursive container type. A recursive container 
+// type is a container type whose value_type is equal to the container type
+// itself. An example for a recursive container type is 
+// boost::filesystem::path, whose iterator has a value_type that is equal to 
+// boost::filesystem::path.
+template<typename C>
+struct IsRecursiveContainer : public IsRecursiveContainerImpl<C>::type {};
+
 // EnableIf<condition>::type is void when 'Cond' is true, and
 // undefined when 'Cond' is false.  To use SFINAE to make a function
 // overload only apply when a particular expression is true, add