[3.5] bpo-29931 fix __lt__ check in ipaddress.ip_interface for both v4 and v6. (GH-879) (#2218)

serhiy-storchaka · web-flow · commit c5a6fb654a28 · 2017-06-15T17:16:55.000+03:00
the original logic was just comparing the network address but this is wrong because if the network address is equal then we need to compare the ip address for breaking the tie add more ip_interface comparison tests. (cherry picked from commit 7bd8d3e)
diff --git a/Lib/ipaddress.py b/Lib/ipaddress.py
@@ -1410,7 +1410,8 @@ def __lt__(self, other):
         if address_less is NotImplemented:
             return NotImplemented
         try:
-            return self.network < other.network
+            return (self.network < other.network or
+                    self.network == other.network and address_less)
         except AttributeError:
             # We *do* allow addresses and interfaces to be sorted. The
             # unassociated address is considered less than all interfaces.
@@ -2100,7 +2101,8 @@ def __lt__(self, other):
         if address_less is NotImplemented:
             return NotImplemented
         try:
-            return self.network < other.network
+            return (self.network < other.network or
+                    self.network == other.network and address_less)
         except AttributeError:
             # We *do* allow addresses and interfaces to be sorted. The
             # unassociated address is considered less than all interfaces.
diff --git a/Lib/test/test_ipaddress.py b/Lib/test/test_ipaddress.py
@@ -1404,14 +1404,35 @@ def testAddressComparison(self):
                         ipaddress.ip_address('::2'))
 
     def testInterfaceComparison(self):
-        self.assertTrue(ipaddress.ip_interface('1.1.1.1') <=
-                        ipaddress.ip_interface('1.1.1.1'))
-        self.assertTrue(ipaddress.ip_interface('1.1.1.1') <=
-                        ipaddress.ip_interface('1.1.1.2'))
-        self.assertTrue(ipaddress.ip_interface('::1') <=
-                        ipaddress.ip_interface('::1'))
-        self.assertTrue(ipaddress.ip_interface('::1') <=
-                        ipaddress.ip_interface('::2'))
+        self.assertTrue(ipaddress.ip_interface('1.1.1.1/24') ==
+                        ipaddress.ip_interface('1.1.1.1/24'))
+        self.assertTrue(ipaddress.ip_interface('1.1.1.1/16') <
+                        ipaddress.ip_interface('1.1.1.1/24'))
+        self.assertTrue(ipaddress.ip_interface('1.1.1.1/24') <
+                        ipaddress.ip_interface('1.1.1.2/24'))
+        self.assertTrue(ipaddress.ip_interface('1.1.1.2/16') <
+                        ipaddress.ip_interface('1.1.1.1/24'))
+        self.assertTrue(ipaddress.ip_interface('1.1.1.1/24') >
+                        ipaddress.ip_interface('1.1.1.1/16'))
+        self.assertTrue(ipaddress.ip_interface('1.1.1.2/24') >
+                        ipaddress.ip_interface('1.1.1.1/24'))
+        self.assertTrue(ipaddress.ip_interface('1.1.1.1/24') >
+                        ipaddress.ip_interface('1.1.1.2/16'))
+
+        self.assertTrue(ipaddress.ip_interface('::1/64') ==
+                        ipaddress.ip_interface('::1/64'))
+        self.assertTrue(ipaddress.ip_interface('::1/64') <
+                        ipaddress.ip_interface('::1/80'))
+        self.assertTrue(ipaddress.ip_interface('::1/64') <
+                        ipaddress.ip_interface('::2/64'))
+        self.assertTrue(ipaddress.ip_interface('::2/48') <
+                        ipaddress.ip_interface('::1/64'))
+        self.assertTrue(ipaddress.ip_interface('::1/80') >
+                        ipaddress.ip_interface('::1/64'))
+        self.assertTrue(ipaddress.ip_interface('::2/64') >
+                        ipaddress.ip_interface('::1/64'))
+        self.assertTrue(ipaddress.ip_interface('::1/64') >
+                        ipaddress.ip_interface('::2/48'))
 
     def testNetworkComparison(self):
         # ip1 and ip2 have the same network address
diff --git a/Misc/NEWS b/Misc/NEWS
@@ -56,6 +56,9 @@ Extension Modules
 Library
 -------
 
+- bpo-29931: Fixed comparison check for ipaddress.ip_interface objects.
+  Patch by Sanjay Sundaresan.
+
 - [Security] bpo-29591: Update expat copy from 2.1.1 to 2.2.0 to get fixes
   of CVE-2016-0718 and CVE-2016-4472. See
   https://sourceforge.net/p/expat/bugs/537/ for more information.
