From 8256546432a3e64b445c79f1996b7ebec3fc131a Mon Sep 17 00:00:00 2001
From: Alessio Quaglino <quaglino@google.com>
Date: Tue, 8 Oct 2024 12:22:25 -0700
Subject: [PATCH] Fix bug in xml_native_writer that was causing frames to be
 skipped.

PiperOrigin-RevId: 683721505
Change-Id: I8622f4ea42ecda934fbc805c429de40e7717fdef
---
 src/xml/xml_native_writer.cc       | 5 -----
 test/xml/xml_native_writer_test.cc | 6 ++++++
 2 files changed, 6 insertions(+), 5 deletions(-)

diff --git a/src/xml/xml_native_writer.cc b/src/xml/xml_native_writer.cc
index 54c18d89..f3f7b085 100644
--- a/src/xml/xml_native_writer.cc
+++ b/src/xml/xml_native_writer.cc
@@ -1718,11 +1718,6 @@ void mjXWriter::Body(XMLElement* elem, mjCBody* body, mjCFrame* frame, string_vi
                                : body->classname;
         Body(OneFrame(elem, fframe), body, fframe, childclass);
       }
-
-      // stop if we reached the frame of the current child body, ignore if there are no bodies
-      if (bframe && bframe == fframe) {
-        break;
-      }
     }
 
     // if there are no bodies, we only want to run the loop once
diff --git a/test/xml/xml_native_writer_test.cc b/test/xml/xml_native_writer_test.cc
index 0d16d895..9f5a8622 100644
--- a/test/xml/xml_native_writer_test.cc
+++ b/test/xml/xml_native_writer_test.cc
@@ -749,6 +749,9 @@ TEST_F(XMLWriterTest, WritesFrameDefaults) {
             </frame>
           </frame>
         </frame>
+        <frame>
+          <light pos="0 0 1"/>
+        </frame>
       </body>
     </worldbody>
   </mujoco>
@@ -775,6 +778,9 @@ TEST_F(XMLWriterTest, WritesFrameDefaults) {
           </frame>
         </frame>
       </frame>
+      <frame>
+        <light pos="0 0 1" dir="0 0 -1"/>
+      </frame>
     </body>
     <frame name="f1">
       <geom size="0.5" quat="0.906308 0 0 0.422618"/>