adding more tests on TF and pytorch serialization - updating configuration for better serialization

transformers/tests/modeling_common_test.py

@@ -17,8 +17,10 @@ from __future__ import division
 from __future__ import print_function
 
 import copy
+import sys
 import os
 import shutil
+import tempfile
 import json
 import random
 import uuid
@@ -31,6 +33,7 @@ from transformers import is_torch_available
 
 if is_torch_available():
     import torch
+    import numpy as np
 
     from transformers import (PretrainedConfig, PreTrainedModel,
                                     BertModel, BertConfig, BERT_PRETRAINED_MODEL_ARCHIVE_MAP,
@@ -38,6 +41,20 @@ if is_torch_available():
 else:
     pytestmark = pytest.mark.skip("Require Torch")
 
+if sys.version_info[0] == 2:
+    import cPickle as pickle
+
+    class TemporaryDirectory(object):
+        """Context manager for tempfile.mkdtemp() so it's usable with "with" statement."""
+        def __enter__(self):
+            self.name = tempfile.mkdtemp()
+            return self.name
+        def __exit__(self, exc_type, exc_value, traceback):
+            shutil.rmtree(self.name)
+else:
+    import pickle
+    TemporaryDirectory = tempfile.TemporaryDirectory
+    unicode = str
 
 def _config_zero_init(config):
     configs_no_init = copy.deepcopy(config)
@@ -57,6 +74,23 @@ class CommonTestCases:
         test_resize_embeddings = True
         test_head_masking = True
 
+        def test_save_load(self):
+            config, inputs_dict = self.model_tester.prepare_config_and_inputs_for_common()
+
+            for model_class in self.all_model_classes:
+                model = model_class(config)
+                model.eval()
+                with torch.no_grad():
+                    outputs = model(**inputs_dict)
+
+                with TemporaryDirectory() as tmpdirname:
+                    model.save_pretrained(tmpdirname)
+                    model = model_class.from_pretrained(tmpdirname)
+                    with torch.no_grad():
+                        after_outputs = model(**inputs_dict)
+                    max_diff = np.amax(np.abs(after_outputs[0].numpy() - outputs[0].numpy()))
+                    self.assertLessEqual(max_diff, 1e-5)
+
         def test_initialization(self):
             config, inputs_dict = self.model_tester.prepare_config_and_inputs_for_common()