From 619255e25aa08d335130d34a781f498dabc352e5 Mon Sep 17 00:00:00 2001
From: Kieran Doonan <kieran.doonan@capitalone.com>
Date: Tue, 5 Jul 2016 11:44:39 +0100
Subject: [PATCH] tag-key and tag-value filters now do a regex match

---
 moto/ec2/utils.py | 16 +++++++++-------
 1 file changed, 9 insertions(+), 7 deletions(-)

diff --git a/moto/ec2/utils.py b/moto/ec2/utils.py
index d8bc6528a..d9ebb4258 100644
--- a/moto/ec2/utils.py
+++ b/moto/ec2/utils.py
@@ -341,17 +341,19 @@ def get_obj_tag_values(obj):
     return tags
 
 def tag_filter_matches(obj, filter_name, filter_values):
+    regex_filters = [re.compile(simple_aws_filter_to_re(f)) for f in filter_values]
     if filter_name == 'tag-key':
-        tag_names = get_obj_tag_names(obj)
-        return len(set(filter_values).intersection(tag_names)) > 0
+        tag_values = get_obj_tag_names(obj)
     elif filter_name == 'tag-value':
         tag_values = get_obj_tag_values(obj)
-        return len(set(filter_values).intersection(tag_values)) > 0
     else:
-        import re
-        tag_value = get_obj_tag(obj, filter_name) or ''
-        regex_filters = [re.compile(simple_aws_filter_to_re(f)) for f in filter_values]
-        return any(regex.match(tag_value) for regex in regex_filters)
+        tag_values = [get_obj_tag(obj, filter_name) or '']
+
+    for tag_value in tag_values:
+        if any(regex.match(tag_value) for regex in regex_filters):
+            return True
+
+    return False
 
 
 filter_dict_attribute_mapping = {