1 files changed, 8 insertions, 2 deletions
diff --git a/src/google/protobuf/util/internal/json_objectwriter.cc b/src/google/protobuf/util/internal/json_objectwriter.cc
index 6e4edd88..c36459a4 100644
--- a/src/google/protobuf/util/internal/json_objectwriter.cc
+++ b/src/google/protobuf/util/internal/json_objectwriter.cc
@@ -176,8 +176,14 @@ void JsonObjectWriter::WritePrefix(StringPiece name) {
   if (!name.empty() || empty_key_ok) {
     WriteChar('"');
     if (!name.empty()) {
-      ArrayByteSource source(name);
-      JsonEscaping::Escape(&source, &sink_);
+      if (use_snake_case_for_field_names_) {
+        string snake_name = ToSnakeCase(name);
+        ArrayByteSource source(snake_name);
+        JsonEscaping::Escape(&source, &sink_);
+      } else {
+        ArrayByteSource source(name);
+        JsonEscaping::Escape(&source, &sink_);
+      }
     }
     stream_->WriteString("\":");
     if (!indent_string_.empty()) WriteChar(' ');