Generate unique random name

Change-Id: I5f8fff33a3cd3d3a55c9c6678a25fd51d96913ea
Closes-Bug: 1735582
(cherry picked from commit 9a39849)

tcutils/util.py

@@ -555,6 +555,14 @@ def get_random_name(prefix=None, constant_prefix='ctest'):
         ret_val = '%s-%s' %(constant_prefix, ret_val)
     return ret_val
 
+def get_unique_random_name(*args, **kwargs):
+    if 'unique_random_name' not in env.keys():
+        env['unique_random_name'] = list()
+    while True:
+        name = get_random_name(*args, **kwargs)
+        if name not in env.unique_random_name:
+            env.unique_random_name.append(name)
+            return name
 
 def gen_str_with_spl_char(size, char_set=None):
     if char_set:

test.py

@@ -10,7 +10,7 @@
 from common import log_orig as contrail_logging
 #from common import config
 import logging as std_logging
-from tcutils.util import get_random_name
+from tcutils.util import get_unique_random_name
 
 def attr(*args, **kwargs):
     """A decorator which applies the  testtools attr decorator
@@ -53,7 +53,7 @@ def id(self):
                     if tag in attributes:
                         return orig
             # A hack to please testtools to get uniq testcase names
-            return get_random_name()
+            return get_unique_random_name()
 
 class BaseTestCase(TagsHack,
                    testtools.testcase.WithAttributes,