API(fluid.layers.array_read/array_write) error message enhancement (#23568)

python/paddle/fluid/layers/control_flow.py

@@ -1314,7 +1314,15 @@ def array_write(x, i, array=None):
             array.append(x)
         return array
 
+    check_variable_and_dtype(i, 'i', ['int64'], 'array_write')
+    check_type(x, 'x', (Variable), 'array_write')
     helper = LayerHelper('array_write', **locals())
+    if array is not None:
+        if not isinstance(
+                array,
+                Variable) or array.type != core.VarDesc.VarType.LOD_TENSOR_ARRAY:
+            raise TypeError(
+                "array should be tensor array vairable in array_write Op")
     if array is None:
         array = helper.create_variable(
             name="{0}.out".format(helper.name),
@@ -1686,6 +1694,7 @@ def array_read(array, i):
         i = i.numpy()[0]
         return array[i]
 
+    check_variable_and_dtype(i, 'i', ['int64'], 'array_read')
     helper = LayerHelper('array_read', **locals())
     if not isinstance(
             array,

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

@@ -21,6 +21,7 @@ import paddle.fluid.layers as layers
 from paddle.fluid.executor import Executor
 from paddle.fluid.backward import append_backward
 from paddle.fluid.framework import default_main_program
+from paddle.fluid import compiler, Program, program_guard
 import numpy
 
 
@@ -125,5 +126,19 @@ class TestArrayReadWrite(unittest.TestCase):
             self.assertAlmostEqual(1.0, g_out_sum_dygraph, delta=0.1)
 
 
+class TestArrayReadWriteOpError(unittest.TestCase):
+    def test_errors(self):
+        with program_guard(Program(), Program()):
+            #for ci coverage
+            x1 = numpy.random.randn(2, 4).astype('int32')
+            x2 = fluid.layers.fill_constant(shape=[1], dtype='int32', value=1)
+            x3 = numpy.random.randn(2, 4).astype('int32')
+
+            self.assertRaises(
+                TypeError, fluid.layers.array_read, array=x1, i=x2)
+            self.assertRaises(
+                TypeError, fluid.layers.array_write, array=x1, i=x2, out=x3)
+
+
 if __name__ == '__main__':
     unittest.main()