chore: import upstream snapshot with attribution

test/dygraph_to_static/test_optional_tensor.py

@@ -0,0 +1,54 @@
+# Copyright (c) 2025 PaddlePaddle Authors. All Rights Reserved.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+import unittest
+
+import numpy as np
+from dygraph_to_static_utils import Dy2StTestBase
+
+import paddle
+
+
+def call_fused_rms_norm(x, y):
+    return paddle.incubate.nn.functional.fused_rms_norm(
+        x,
+        y,
+        None,
+        1e-6,
+        begin_norm_axis=1,
+    )
+
+
+class TestOptionalTensorOutput(Dy2StTestBase):
+    def test_fused_rms_norm(self):
+        if not paddle.is_compiled_with_cuda():
+            return
+        fn = call_fused_rms_norm
+        static_fn = paddle.jit.to_static(fn)
+
+        x = paddle.randn([1410, 5120], dtype='float32')
+        y = paddle.randn([5120], dtype='float32')
+        x.stop_gradient = False
+
+        out_1_dy, out_2_dy = fn(x, y)
+        out_1_st, out_2_st = static_fn(x, y)
+        np.testing.assert_allclose(
+            out_1_dy.numpy(), out_1_st.numpy(), atol=1e-6, rtol=1e-6
+        )
+        self.assertFalse(out_2_dy._is_initialized())
+        self.assertFalse(out_2_st._is_initialized())
+
+
+if __name__ == '__main__':
+    unittest.main()