From 729d4f3ab56d0d25e89654dc1dd33ec6a1cf1074 Mon Sep 17 00:00:00 2001
From: Bob Halley <halley@dnspython.org>
Date: Fri, 13 May 2016 06:43:36 -0700
Subject: [PATCH] dns.message.make_query() now interprets any setting that
 implies EDNS as a request to turn on EDNS, if use_edns has not been set
 explicitly.

---
 dns/message.py        | 25 +++++++++++++++++++++++--
 tests/test_message.py | 21 +++++++++++++++++++++
 2 files changed, 44 insertions(+), 2 deletions(-)

diff --git a/dns/message.py b/dns/message.py
index 1b310869..184100da 100644
--- a/dns/message.py
+++ b/dns/message.py
@@ -1043,7 +1043,7 @@ def from_file(f):
 
 
 def make_query(qname, rdtype, rdclass=dns.rdataclass.IN, use_edns=None,
-               want_dnssec=False, ednsflags=0, payload=1280,
+               want_dnssec=False, ednsflags=None, payload=None,
                request_payload=None, options=None):
     """Make a query message.
 
@@ -1088,7 +1088,28 @@ def make_query(qname, rdtype, rdclass=dns.rdataclass.IN, use_edns=None,
     m.flags |= dns.flags.RD
     m.find_rrset(m.question, qname, rdclass, rdtype, create=True,
                  force_unique=True)
-    m.use_edns(use_edns, ednsflags, payload, request_payload, options)
+    # only pass keywords on to use_edns if they have been set to a
+    # non-None value.  Setting a field will turn EDNS on if it hasn't
+    # been configured.
+    kwargs = {}
+    if ednsflags is not None:
+        kwargs['ednsflags'] = ednsflags
+        if use_edns is None:
+            use_edns = 0
+    if payload is not None:
+        kwargs['payload'] = payload
+        if use_edns is None:
+            use_edns = 0
+    if request_payload is not None:
+        kwargs['request_payload'] = request_payload
+        if use_edns is None:
+            use_edns = 0
+    if options is not None:
+        kwargs['options'] = options
+        if use_edns is None:
+            use_edns = 0
+    kwargs['edns'] = use_edns
+    m.use_edns(**kwargs)
     m.want_dnssec(want_dnssec)
     return m
 
diff --git a/tests/test_message.py b/tests/test_message.py
index 79562654..4513b959 100644
--- a/tests/test_message.py
+++ b/tests/test_message.py
@@ -21,6 +21,7 @@ except ImportError:
 import binascii
 
 import dns.exception
+import dns.flags
 import dns.message
 from dns._compat import xrange
 
@@ -179,5 +180,25 @@ class MessageTestCase(unittest.TestCase):
         m.use_edns(1)
         self.failUnless((m.ednsflags >> 16) & 0xFF == 1)
 
+    def test_SettingNoEDNSOptionsImpliesNoEDNS(self):
+        m = dns.message.make_query('foo', 'A')
+        self.failUnless(m.edns == -1)
+
+    def test_SettingEDNSFlagsImpliesEDNS(self):
+        m = dns.message.make_query('foo', 'A', ednsflags=dns.flags.DO)
+        self.failUnless(m.edns == 0)
+
+    def test_SettingEDNSPayloadImpliesEDNS(self):
+        m = dns.message.make_query('foo', 'A', payload=4096)
+        self.failUnless(m.edns == 0)
+
+    def test_SettingEDNSRequestPayloadImpliesEDNS(self):
+        m = dns.message.make_query('foo', 'A', request_payload=4096)
+        self.failUnless(m.edns == 0)
+
+    def test_SettingOptionsImpliesEDNS(self):
+        m = dns.message.make_query('foo', 'A', options=[])
+        self.failUnless(m.edns == 0)
+
 if __name__ == '__main__':
     unittest.main()
-- 
2.47.3