1 files changed, 21 insertions, 1 deletions
diff --git a/src/google/protobuf/util/message_differencer.cc b/src/google/protobuf/util/message_differencer.cc
index 47237e5a..0f879dc7 100644
--- a/src/google/protobuf/util/message_differencer.cc
+++ b/src/google/protobuf/util/message_differencer.cc
@@ -238,9 +238,25 @@ void MessageDifferencer::TreatAsSet(const FieldDescriptor* field) {
   GOOGLE_CHECK(key_comparator == NULL)
       << "Cannot treat this repeated field as both Map and Set for"
       << " comparison.  Field name is: " << field->full_name();
+  GOOGLE_CHECK(list_fields_.find(field) == list_fields_.end())
+      << "Cannot treat the same field as both SET and LIST. Field name is: "
+      << field->full_name();
   set_fields_.insert(field);
 }
 
+void MessageDifferencer::TreatAsList(const FieldDescriptor* field) {
+  GOOGLE_CHECK(field->is_repeated()) << "Field must be repeated: "
+                              << field->full_name();
+  const MapKeyComparator* key_comparator = GetMapKeyComparator(field);
+  GOOGLE_CHECK(key_comparator == NULL)
+      << "Cannot treat this repeated field as both Map and Set for"
+      << " comparison.  Field name is: " << field->full_name();
+  GOOGLE_CHECK(set_fields_.find(field) == set_fields_.end())
+      << "Cannot treat the same field as both SET and LIST. Field name is: "
+      << field->full_name();
+  list_fields_.insert(field);
+}
+
 void MessageDifferencer::TreatAsMap(const FieldDescriptor* field,
                                     const FieldDescriptor* key) {
   GOOGLE_CHECK(field->is_repeated()) << "Field must be repeated: "
@@ -255,6 +271,9 @@ void MessageDifferencer::TreatAsMap(const FieldDescriptor* field,
   GOOGLE_CHECK(set_fields_.find(field) == set_fields_.end())
       << "Cannot treat this repeated field as both Map and Set for "
       << "comparison.";
+  GOOGLE_CHECK(list_fields_.find(field) == list_fields_.end())
+      << "Cannot treat this repeated field as both Map and List for "
+      << "comparison.";
   MapKeyComparator* key_comparator =
       new MultipleFieldsMapKeyComparator(this, key);
   owned_key_comparators_.push_back(key_comparator);
@@ -920,7 +939,8 @@ bool MessageDifferencer::CheckPathChanged(
 bool MessageDifferencer::IsTreatedAsSet(const FieldDescriptor* field) {
   if (!field->is_repeated()) return false;
   if (field->is_map()) return true;
-  if (repeated_field_comparison_ == AS_SET) return true;
+  if (repeated_field_comparison_ == AS_SET)
+    return list_fields_.find(field) == list_fields_.end();
   return (set_fields_.find(field) != set_fields_.end());
 }