improve one more unittest: raise proper assertion instead of failing with non-existen...

diff --git a/testing/test_deltatar.py b/testing/test_deltatar.py
index 112b546..e7cbe97 100644 (file)
--- a/testing/test_deltatar.py
+++ b/testing/test_deltatar.py
@@ -389,6 +389,7 @@ class DeltaTarTest(BaseTest):
 
         # this should automatically restore the huge file
         f = deltatar.open_index(index_path, 'r')
+        offset = None
         while True:
             l = f.readline()
             if not len(l):
@@ -399,6 +400,8 @@ class DeltaTarTest(BaseTest):
                 offset = data['offset']
                 break
 
+        assert offset is not None
+
         fo = open(tar_path, 'rb')
         fo.seek(offset)
         def new_volume_handler(mode, tarobj, base_name, volume_number):