1 files changed, 17 insertions, 7 deletions

diff --git a/src/google/protobuf/util/message_differencer.h b/src/google/protobuf/util/message_differencer.h
index b7d4de00..bbcf8498 100644
--- a/src/google/protobuf/util/message_differencer.h
+++ b/src/google/protobuf/util/message_differencer.h
@@ -64,6 +64,7 @@ class Printer;
 
 namespace util {
 
+class DefaultFieldComparator;
 class FieldContext;  // declared below MessageDifferencer
 
 // A basic differencer that can be used to determine
@@ -174,10 +175,8 @@ class LIBPROTOBUF_EXPORT MessageDifferencer {
 
     // If "field" is a repeated field which is being treated as a map or
     // a set (see TreatAsMap() and TreatAsSet(), below), new_index indicates
-    // the index the position to which the element has moved.  This only
-    // applies to ReportMoved() and (in the case of TreatAsMap())
-    // ReportModified().  In all other cases, "new_index" will have the same
-    // value as "index".
+    // the index the position to which the element has moved.  If the element
+    // has not moved, "new_index" will have the same value as "index".
     int new_index;
 
     // For unknown fields, these are the pointers to the UnknownFieldSet
@@ -372,7 +371,7 @@ class LIBPROTOBUF_EXPORT MessageDifferencer {
                  // repeated fields have different numbers of elements, the
                  // unpaired elements are reported using ReportAdded() or
                  // ReportDeleted().
-    AS_SET,      // Treat all the repeated fields as sets by default.
+    AS_SET,      // Treat all the repeated fields as sets.
                  // See TreatAsSet(), as below.
   };
 
@@ -386,6 +385,11 @@ class LIBPROTOBUF_EXPORT MessageDifferencer {
   // the only differences between the compared messages is that some fields
   // have been moved, then the comparison returns true.
   //
+  // Note that despite the name of this method, this is really
+  // comparison as multisets: if one side of the comparison has a duplicate
+  // in the repeated field but the other side doesn't, this will count as
+  // a mismatch.
+  //
   // If the scope of comparison is set to PARTIAL, then in addition to what's
   // above, extra values added to repeated fields of the second message will
   // not cause the comparison to fail.
@@ -470,6 +474,10 @@ class LIBPROTOBUF_EXPORT MessageDifferencer {
       const FieldDescriptor* field,
       const MapKeyComparator* key_comparator);
 
+  // Initiates and returns a new instance of MultipleFieldsMapKeyComparator.
+  MapKeyComparator* CreateMultipleFieldsMapKeyComparator(
+      const std::vector<std::vector<const FieldDescriptor*> >& key_field_paths);
+
   // Add a custom ignore criteria that is evaluated in addition to the
   // ignored fields added with IgnoreField.
   // Takes ownership of ignore_criteria.
@@ -660,6 +668,8 @@ class LIBPROTOBUF_EXPORT MessageDifferencer {
   };
 
  private:
+  friend class DefaultFieldComparator;
+
   // A MapKeyComparator to be used in TreatAsMapUsingKeyComparator.
   // Implementation of this class needs to do field value comparison which
   // relies on some private methods of MessageDifferencer. That's why this
@@ -811,7 +821,7 @@ class LIBPROTOBUF_EXPORT MessageDifferencer {
 
   // If "any" is of type google.protobuf.Any, extract its payload using
   // DynamicMessageFactory and store in "data".
-  bool UnpackAny(const Message& any, google::protobuf::scoped_ptr<Message>* data);
+  bool UnpackAny(const Message& any, std::unique_ptr<Message>* data);
 
   // Checks if index is equal to new_index in all the specific fields.
   static bool CheckPathChanged(const std::vector<SpecificField>& parent_fields);
@@ -852,7 +862,7 @@ class LIBPROTOBUF_EXPORT MessageDifferencer {
 
   string* output_string_;
 
-  google::protobuf::scoped_ptr<DynamicMessageFactory> dynamic_message_factory_;
+  std::unique_ptr<DynamicMessageFactory> dynamic_message_factory_;
   GOOGLE_DISALLOW_EVIL_CONSTRUCTORS(MessageDifferencer);
 };