[API] Fix shape=int for size_args_decorator

python/paddle/utils/decorator_utils.py

@@ -333,6 +333,9 @@ def wrapped_func(*args: Any, **kwargs: Any) -> Any:
             kwargs['shape'] = list(args)
             args = ()
 
+        if 'shape' in kwargs and isinstance(kwargs['shape'], int):
+            kwargs['shape'] = [kwargs['shape']]
+
         return func(*args, **kwargs)
 
     wrapped_func.__signature__ = inspect.signature(func)

test/legacy_test/test_int_shape.py

@@ -0,0 +1,36 @@
+# 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
+
+from utils import dygraph_guard
+
+import paddle
+
+
+class TestIntShape(unittest.TestCase):
+    def test_eager(self):
+        with dygraph_guard():
+            for shape in [
+                2,
+                0,
+                10,
+            ]:
+                for func in [paddle.rand]:
+                    x = func(shape=shape)
+                    self.assertEqual(x.shape, [shape])
+
+
+if __name__ == "__main__":
+    unittest.main()