Check for duplicated names when setting element names.

PiperOrigin-RevId: 778827590
Change-Id: I77a208c1571cf735cae80840ea830aa347681f71

doc/APIreference/functions.rst

@@ -4235,7 +4235,7 @@ Attribute setters
 
 .. mujoco-include:: mjs_setName
 
-Set element's name.
+Set element's name, return 0 on success.
 
 .. _mjs_setBuffer:
 

doc/changelog.rst

@@ -17,6 +17,9 @@ General
   :ref:`visual/global/cameraid<visual-global-cameraid>`.
 - Added support to only sync the state in the Python :ref:`passive viewer<PyViewerPassive>`'s ``Sync`` method, this is
   useful to improve performance. The default behavior is unchanged and copies the entire model and data.
+- In the mjSpec C API, directly setting an element's name using :ref:`mjs_setString` has been replaced with a new
+  function :ref:`mjs_setName` which allows checking for naming collisions at set-time rather than compile-time, for
+  earlier catching of errors.
 
 Bug fixes
 ^^^^^^^^^

doc/includes/references.h

@@ -3456,7 +3456,7 @@ mjsElement* mjs_firstChild(mjsBody* body, mjtObj type, int recurse);
 mjsElement* mjs_nextChild(mjsBody* body, mjsElement* child, int recurse);
 mjsElement* mjs_firstElement(mjSpec* s, mjtObj type);
 mjsElement* mjs_nextElement(mjSpec* s, mjsElement* element);
-void mjs_setName(mjsElement* element, const char* name);
+int mjs_setName(mjsElement* element, const char* name);
 void mjs_setBuffer(mjByteVec* dest, const void* array, int size);
 void mjs_setString(mjString* dest, const char* text);
 void mjs_setStringVec(mjStringVec* dest, const char* text);