Add timestamp to figure save directory

.gitignore

@@ -76,5 +76,5 @@ $RECYCLE.BIN/
 .pytest_cache/
 sunpydata.sqlite
 
-result_images
+result_images*
 .pytest_cache

sunpy/conftest.py

@@ -14,7 +14,7 @@
     matplotlib.use('Agg')
 
 from sunpy.tests.hash import HASH_LIBRARY_NAME
-from sunpy.tests.helpers import new_hash_library
+from sunpy.tests.helpers import new_hash_library, test_fig_dir
 from sunpy.extern import six
 
 import pytest
@@ -49,7 +49,7 @@ def pytest_runtest_setup(item):
 def pytest_unconfigure(config):
     if len(new_hash_library) > 0:
         # Write the new hash library in JSON
-        hashfile = os.path.join('result_images', HASH_LIBRARY_NAME)
+        hashfile = os.path.join(test_fig_dir, HASH_LIBRARY_NAME)
         with open(hashfile, 'w') as outfile:
             json.dump(new_hash_library, outfile, sort_keys=True, indent=4, separators=(',', ': '))
 

sunpy/tests/helpers.py

@@ -7,6 +7,7 @@
 import tempfile
 import platform
 import os
+import datetime
 
 import pytest
 import numpy as np
@@ -52,6 +53,7 @@ def warnings_as_errors(request):
 
 hash_library = hash.hash_library
 new_hash_library = {}
+test_fig_dir = 'result_images_{:%H%M%S}'.format(datetime.datetime.now())
 
 
 def figure_test(test_function):
@@ -85,9 +87,9 @@ def wrapper(*args, **kwargs):
             fig = plt.gcf()
 
         # Save the image that was generated
-        if not os.path.exists('result_images'):
-            os.mkdir('result_images')
-        result_image_loc = os.path.join('result_images', '{}.png'.format(name))
+        if not os.path.exists(test_fig_dir):
+            os.mkdir(test_fig_dir)
+        result_image_loc = os.path.join(test_fig_dir, '{}.png'.format(name))
         plt.savefig(result_image_loc)
         plt.close()