[API]Fix paddle.arange infershape always -1 (#52764)

python/paddle/fluid/tests/unittests/test_arange.py

@@ -151,6 +151,7 @@ class TestArangeAPI(unittest.TestCase):
 
         expected_data = np.arange(0, 5, 1).astype(np.float32)
         self.assertEqual((out == expected_data).all(), True)
+        self.assertListEqual(list(x1.shape), [5])
 
 
 class TestArangeImperative(unittest.TestCase):

python/paddle/tensor/creation.py

@@ -1293,6 +1293,14 @@ def arange(start=0, end=None, step=1, dtype=None, name=None):
         end = start
         start = 0
 
+    out_shape = None
+    if not in_dygraph_mode() and (
+        not isinstance(start, Variable)
+        and not isinstance(end, Variable)
+        and not isinstance(step, Variable)
+    ):
+        out_shape = [int(math.ceil((end - start) / step))]
+
     if not isinstance(dtype, core.VarDesc.VarType):
         dtype = convert_np_dtype_to_dtype_(dtype)
 
@@ -1324,13 +1332,6 @@ def arange(start=0, end=None, step=1, dtype=None, name=None):
             'range/arange',
         )
         helper = LayerHelper('range', **locals())
-        out_shape = None
-        if (
-            not isinstance(start, Variable)
-            and not isinstance(end, Variable)
-            and not isinstance(step, Variable)
-        ):
-            out_shape = [int(math.ceil((end - start) / step))]
         out = helper.create_variable_for_type_inference(dtype, shape=out_shape)
         helper.append_op(
             type='range',