Merge pull request #1396 from lkissin2/utilstest

Testing _utils.py

openmc/_utils.py

@@ -60,9 +60,10 @@ def download(url, checksum=None, as_browser=False, **kwargs):
     if checksum is not None:
         downloadsum = hashlib.md5(open(basename, 'rb').read()).hexdigest()
         if downloadsum != checksum:
-            raise IOError("MD5 checksum for {} does not match. If this is your first "
-                          "time receiving this message, please re-run the script. "
-                          "Otherwise, please contact OpenMC developers by emailing "
+            raise IOError("MD5 checksum for {} does not match. If this is "
+                          "your first time receiving this message, please "
+                          "re-run the script. Otherwise, please contact "
+                          "OpenMC developers by emailing "
                           "openmc-users@googlegroups.com.".format(basename))
 
     return basename

tests/unit_tests/test_utils.py

@@ -0,0 +1,26 @@
+import os
+import filecmp
+
+from openmc import _utils
+import pytest
+
+@pytest.fixture()
+def download_photos(run_in_tmpdir):
+    """use _utils download() function to download the same picture three times,
+       twice to get unique names, & a third time to use the already downloaded
+       block of code"""
+    _utils.download("https://i.ibb.co/HhKFc8x/small.jpg")
+    _utils.download("https://tinyurl.com/y4t38ugb")
+    _utils.download("https://tinyurl.com/y4t38ugb", as_browser=True)
+
+
+def test_checksum_error(run_in_tmpdir):
+    """use download() in such a way that will test the checksum error line"""
+    phrase = "MD5 checksum for y4t38ugb"
+    with pytest.raises(OSError, match=phrase):
+        _utils.download("https://tinyurl.com/y4t38ugb", as_browser=True,
+                        checksum="not none")
+
+
+def test_photos(download_photos):
+    assert filecmp.cmp("small.jpg", "y4t38ugb")