Make resolver use_edns() conform to its docstring; slightly improve use_edns() logic.

1 files changed, 10 insertions, 0 deletions

diff --git a/tests/test_resolver.py b/tests/test_resolver.py
index 82d62b4..e77466d 100644
--- a/tests/test_resolver.py
+++ b/tests/test_resolver.py
@@ -512,6 +512,16 @@ class BaseResolverTests(unittest.TestCase):
         qnames = res._get_qnames_to_try(qname, None)
         self.assertEqual(qnames, [qname])
 
+    def testUseEDNS(self):
+        r = dns.resolver.Resolver(configure=False)
+        r.use_edns(None)
+        self.assertEqual(r.edns, -1)
+        r.use_edns(False)
+        self.assertEqual(r.edns, -1)
+        r.use_edns(True)
+        self.assertEqual(r.edns, 0)
+
+
 @unittest.skipIf(not _network_available, "Internet not reachable")
 class LiveResolverTests(unittest.TestCase):
     def testZoneForName1(self):