Test - Added downloaded directory not empty check in test_datasets_utils (#844)

Author: Ashok93

test/test_datasets_utils.py

@@ -1,3 +1,4 @@
+import os
 import shutil
 import tempfile
 import torch
@@ -11,12 +12,14 @@ def test_download_url(self):
         temp_dir = tempfile.mkdtemp()
         url = "http://github.com/pytorch/vision/archive/master.zip"
         utils.download_url(url, temp_dir)
+        assert not len(os.listdir(temp_dir)) == 0, 'The downloaded root directory is empty after download.'
         shutil.rmtree(temp_dir)
 
     def test_download_url_retry_http(self):
         temp_dir = tempfile.mkdtemp()
         url = "https://github.com/pytorch/vision/archive/master.zip"
         utils.download_url(url, temp_dir)
+        assert not len(os.listdir(temp_dir)) == 0, 'The downloaded root directory is empty after download.'
         shutil.rmtree(temp_dir)