chore: import upstream snapshot with attribution

test/legacy_test/feed_data_reader.py

@@ -0,0 +1,49 @@
+# Copyright (c) 2019 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.
+
+from paddle import base
+from paddle.base.framework import Variable
+
+
+def cyclic_reader(reader):
+    def __reader__():
+        while True:
+            yield from reader()
+
+    return __reader__
+
+
+class FeedDataReader:
+    def __init__(self, feed_list, reader):
+        self._feed_list = []
+        for var in feed_list:
+            if isinstance(var, Variable):
+                self._feed_list.append(var.name)
+            else:
+                self._feed_list.append(var)
+
+        self._reader = cyclic_reader(reader)
+        self._iter = self._reader()
+
+    def _feed_executor(self):
+        next_data = next(self._iter)
+        feed_data = {}
+        assert len(self._feed_list) == len(next_data)
+        for key, value in zip(self._feed_list, next_data):
+            feed_data[key] = value
+        return feed_data
+
+    def get_next(self, exe, program):
+        assert isinstance(exe, base.Executor), "exe must be Executor"
+        return self._feed_executor()