From 8950f756fe03774d8a34e6fd997372328c056438 Mon Sep 17 00:00:00 2001
From: Jaisen Mathai <jaisen@jmathai.com>
Date: Wed, 6 Dec 2017 15:46:00 -0800
Subject: [PATCH] Make reset_dbs() / restore_dbs() more robust #260 (#263)

* Make reset_dbs() / restore_dbs() more robust

If reset_dbs() is called and the test errors restore_dbs() is not called. On Windows this leads to an error the next time they're called because ~/hash.json-test and ~/location.json-test still exist.

* Add rename function to compatability module for 2.7 support
---
 elodie/compatability.py | 10 ++++++++++
 elodie/tests/helper.py  | 36 ++++++++++++++++++++++++------------
 2 files changed, 34 insertions(+), 12 deletions(-)

diff --git a/elodie/compatability.py b/elodie/compatability.py
index e0d8576..d4a68dd 100644
--- a/elodie/compatability.py
+++ b/elodie/compatability.py
@@ -63,3 +63,13 @@ def _copyfile(src, dst):
             os.close(fout)
         except:
             pass
+
+
+# If you want cross-platform overwriting of the destination, 
+# use os.replace() instead of rename().
+# https://docs.python.org/3/library/os.html#os.rename
+def _rename(src, dst):
+    if (constants.python_version == 3):
+        return os.replace(src, dst)
+    else:
+        return os.rename(src, dst)
diff --git a/elodie/tests/helper.py b/elodie/tests/helper.py
index bc17951..bda3a34 100644
--- a/elodie/tests/helper.py
+++ b/elodie/tests/helper.py
@@ -14,6 +14,7 @@ import urllib
 from datetime import datetime
 from datetime import timedelta
 
+from elodie.compatability import _rename
 from elodie import constants
 
 def checksum(file_path, blocksize=65536):
@@ -148,19 +149,30 @@ def isclose(a, b, rel_tol = 1e-8):
             diff <= abs(rel_tol * b))
 
 def reset_dbs():
-    hash_db = constants.hash_db
-    if os.path.isfile(hash_db):
-        os.rename(hash_db, '{}-test'.format(hash_db))
-
-    location_db = constants.location_db
-    if os.path.isfile(location_db):
-        os.rename(location_db, '{}-test'.format(location_db))
-
-def restore_dbs():
+    """ Back up hash_db and location_db """
     hash_db = '{}-test'.format(constants.hash_db)
-    if os.path.isfile(hash_db):
-        os.rename(hash_db, hash_db.replace('-test', ''))
+    if not os.path.isfile(hash_db):
+	    hash_db = constants.hash_db
+	    if os.path.isfile(hash_db):
+	        _rename(hash_db, '{}-test'.format(hash_db))
+    #else restore_dbs wasn't called by a previous test, keep the
+    #existing hash_db backup
+	
 
     location_db = '{}-test'.format(constants.location_db)
     if os.path.isfile(location_db):
-        os.rename(location_db, location_db.replace('-test', ''))
+	    location_db = constants.location_db
+	    if os.path.isfile(location_db):
+	        _rename(location_db, '{}-test'.format(location_db))
+    #else restore_dbs wasn't called by a previous test, keep the
+    #existing location_db backup
+
+def restore_dbs():
+    """ Restore back ups of hash_db and location_db """
+    hash_db = '{}-test'.format(constants.hash_db)
+    if os.path.isfile(hash_db):
+        _rename(hash_db, hash_db.replace('-test', ''))
+
+    location_db = '{}-test'.format(constants.location_db)
+    if os.path.isfile(location_db):
+        _rename(location_db, location_db.replace('-test', ''))