update unittest

paddle/fluid/operators/read_op.cc

@@ -66,6 +66,7 @@ class ReadOp : public framework::OperatorBase {
     std::vector<std::string> out_arg_names = Outputs("Out");
     std::vector<framework::LoDTensor> ins;
     reader->ReadNext(&ins);
+    PADDLE_ENFORCE(!ins.empty(), "There is no next data.");
     PADDLE_ENFORCE_EQ(ins.size(), out_arg_names.size());
     for (size_t i = 0; i < ins.size(); ++i) {
       auto* out =

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

@@ -26,11 +26,14 @@ def simple_fc_net(use_feed):
         img = fluid.layers.data(name='image', shape=[784], dtype='float32')
         label = fluid.layers.data(name='label', shape=[1], dtype='int64')
     else:
-        reader = fluid.layers.open_recordio_file(
-            filename='./mnist.recordio',
+        reader = fluid.layers.open_files(
+            filenames=['./mnist.recordio'],
             shapes=[[-1, 784], [-1, 1]],
             lod_levels=[0, 0],
-            dtypes=['float32', 'int64'])
+            dtypes=['float32', 'int64'],
+            thread_num=1,
+            for_parallel=True)
+        reader = fluid.layers.io.double_buffer(reader)
         img, label = fluid.layers.read_file(reader)
     hidden = img
     for _ in xrange(4):
@@ -51,11 +54,14 @@ def fc_with_batchnorm(use_feed):
         img = fluid.layers.data(name='image', shape=[784], dtype='float32')
         label = fluid.layers.data(name='label', shape=[1], dtype='int64')
     else:
-        reader = fluid.layers.open_recordio_file(
-            filename='./mnist.recordio',
+        reader = fluid.layers.open_files(
+            filenames=['mnist.recordio'],
             shapes=[[-1, 784], [-1, 1]],
             lod_levels=[0, 0],
-            dtypes=['float32', 'int64'])
+            dtypes=['float32', 'int64'],
+            thread_num=1,
+            for_parallel=True)
+        reader = fluid.layers.io.double_buffer(reader)
         img, label = fluid.layers.read_file(reader)
 
     hidden = img