Check for duplicated names when setting element names.

PiperOrigin-RevId: 778827590
Change-Id: I77a208c1571cf735cae80840ea830aa347681f71

python/mujoco/codegen/generate_spec_bindings.py

@@ -677,7 +677,9 @@ def generate_name() -> None:
         return mjs_getName(self.element);
       }},
       [](raw::{titlecase}& self, std::string& name) -> void {{
-        mjs_setName(self.element, name.c_str());
+        if (mjs_setName(self.element, name.c_str())) {{
+          throw pybind11::value_error(mjs_getError(mjs_getSpec(self.element)));
+        }}
       }}, py::return_value_policy::reference_internal);
     """
     print(code)

python/mujoco/introspect/functions.py

@@ -10194,7 +10194,7 @@ FUNCTIONS: Mapping[str, FunctionDecl] = dict([
     ('mjs_setName',
      FunctionDecl(
          name='mjs_setName',
-         return_type=ValueType(name='void'),
+         return_type=ValueType(name='int'),
          parameters=(
              FunctionParameterDecl(
                  name='element',
@@ -10209,7 +10209,7 @@ FUNCTIONS: Mapping[str, FunctionDecl] = dict([
                  ),
              ),
          ),
-         doc="Set element's name.",
+         doc="Set element's name, return 0 on success.",
      )),
     ('mjs_setBuffer',
      FunctionDecl(

python/mujoco/specs_test.py

@@ -887,7 +887,7 @@ class SpecsTest(absltest.TestCase):
       ):
         s.compile()
 
-  def test_recompile_error(self):
+  def test_duplicate_name_error(self):
     main_xml = """
     <mujoco>
       <worldbody>
@@ -899,16 +899,11 @@ class SpecsTest(absltest.TestCase):
     """
 
     spec = mujoco.MjSpec.from_string(main_xml)
-    model = spec.compile()
-    data = mujoco.MjData(model)
-
     spec.add_material().name = 'yellow'
-    spec.add_material().name = 'yellow'
-
     with self.assertRaisesRegex(
         ValueError, "Error: repeated name 'yellow' in material"
     ):
-      spec.recompile(model, data)
+      spec.add_material().name = 'yellow'
 
   def test_delete_unused_plugin(self):
     spec = mujoco.MjSpec.from_string("""