From a82ec8bcbf3fe1cefdc62ab95956454dd0bff70a Mon Sep 17 00:00:00 2001
From: Bob Halley <halley@dnspython.org>
Date: Sat, 5 Jan 2019 11:18:40 -0800
Subject: [PATCH] Render type 0 in text as "TYPE0" not "NONE".  [Issue #326]

---
 dns/rdatatype.py             | 3 +++
 tests/test_rdtypeandclass.py | 3 +++
 2 files changed, 6 insertions(+)

diff --git a/dns/rdatatype.py b/dns/rdatatype.py
index b247bc9c..e2a0dd68 100644
--- a/dns/rdatatype.py
+++ b/dns/rdatatype.py
@@ -170,6 +170,9 @@ _by_text = {
 # would cause the mapping not to be true inverse.
 
 _by_value = {y: x for x, y in _by_text.items()}
+# Render type 0 as "TYPE0" not "NONE", as NONE is a dnspython-ism and not
+# an official mnemonic.
+_by_value[0] = 'TYPE0'
 
 _metatypes = {
     OPT: True
diff --git a/tests/test_rdtypeandclass.py b/tests/test_rdtypeandclass.py
index 5d940a01..bf96220f 100644
--- a/tests/test_rdtypeandclass.py
+++ b/tests/test_rdtypeandclass.py
@@ -121,5 +121,8 @@ class RdTypeAndClassTestCase(unittest.TestCase):
             dns.rdatatype.to_text(65536)
         self.failUnlessRaises(ValueError, bad)
 
+    def test_type0_totext(self):
+        self.failUnless(dns.rdatatype.to_text(0) == 'TYPE0')
+
 if __name__ == '__main__':
     unittest.main()
-- 
2.47.3