func-tests: add ixfr scenarios

tests-extra/tests/ixfr/from_differences/04_change/example.com.zone

+$ORIGIN example.com.
+$TTL 3600
+
+@	SOA	dns1 hostmaster 2010111203 10800 3600 1209600 7200
+	NS	dns1
+	NS	dns2
+	MX	10 mail
+
+dns1	A	192.0.2.1
+	A	1.1.1.1
+
+dns2	A	192.0.2.2
+	AAAA	2001:DB8::2
+
+mail	A	192.0.2.3
+	AAAA	2001:DB8::3
+
+ch1	A	1.2.3.4
+
+ch2	AAAA	::1
+	TXT	"some_text"
+
+ch3	MX	10 ch1.example.com.
+	MX	20 ch2.example.com.

tests-extra/tests/ixfr/from_differences/04_change/example.com.zone.1

+$ORIGIN example.com.
+$TTL 3600
+
+@	SOA	dns1 hostmaster 2010111204 10800 3600 1209600 7200
+	NS	dns1
+	NS	dns2
+	MX	10 mail
+
+dns1	A	192.0.2.1
+	A	1.1.1.1
+
+dns2	A	192.0.2.2
+	AAAA	2001:DB8::2
+
+mail	A	192.0.2.3
+	AAAA	2001:DB8::3
+
+; Changed rdata in one record rrset.
+ch1	A	1.1.1.1
+
+ch2	AAAA	::1
+	TXT	"some_text"
+
+ch3	MX	10 ch1.example.com.
+	MX	20 ch2.example.com.

tests-extra/tests/ixfr/from_differences/04_change/example.com.zone.2

+$ORIGIN example.com.
+$TTL 3600
+
+@	SOA	dns1 hostmaster 2010111205 10800 3600 1209600 7200
+	NS	dns1
+	NS	dns2
+	MX	10 mail
+
+dns1	A	192.0.2.1
+	A	1.1.1.1
+
+dns2	A	192.0.2.2
+	AAAA	2001:DB8::2
+
+mail	A	192.0.2.3
+	AAAA	2001:DB8::3
+
+ch1	A	1.1.1.1
+
+; Changed rdata in two rrsets node.
+ch2	AAAA	::1
+	TXT	"some_better_text"
+
+ch3	MX	10 ch1.example.com.
+	MX	20 ch2.example.com.

tests-extra/tests/ixfr/from_differences/04_change/example.com.zone.3

+$ORIGIN example.com.
+$TTL 3600
+
+@	SOA	dns1 hostmaster 2010111206 10800 3600 1209600 7200
+	NS	dns1
+	NS	dns2
+	MX	10 mail
+
+dns1	A	192.0.2.1
+	A	1.1.1.1
+
+dns2	A	192.0.2.2
+	AAAA	2001:DB8::2
+
+mail	A	192.0.2.3
+	AAAA	2001:DB8::3
+
+ch1	A	1.1.1.1
+
+ch2	AAAA	::1
+	TXT	"some_better_text"
+
+; Changed rdata in two record rrset.
+ch3	MX	10 mail.example.com.
+	MX	40 ch2.example.com.

tests-extra/tests/ixfr/from_differences/04_change/step.py

+#!/usr/bin/env python3
+
+'''Change record/records.'''
+
+def run(i):
+    i.test.start()
+
+    i.check()
+    i.check_rec("ch1", "A", "1.2.3.4")
+    i.check_rec("ch2", "AAAA", "::1")
+    i.check_rec("ch2", "TXT", "some_text")
+    i.check_rec("ch3", "MX", "10 ch1.example.com.")
+    i.check_rec("ch3", "MX", "20 ch2.example.com.")
+
+    i.check(1)
+    i.check_rec("ch1", "A", nordata="1.2.3.4")
+    i.check_rec("ch1", "A", "1.1.1.1")
+
+    i.check(2)
+    i.check_rec("ch2", "AAAA", "::1")
+    i.check_rec("ch2", "TXT", nordata="some_text")
+    i.check_rec("ch2", "TXT", "some_better_text")
+
+    i.check(3)
+    i.check_rec("ch3", "MX", nordata="10 ch1.example.com.")
+    i.check_rec("ch3", "MX", "10 mail.example.com.")
+    i.check_rec("ch3", "MX", nordata="20 ch2.example.com.")
+    i.check_rec("ch3", "MX", "40 ch2.example.com.")
+
+    i.test.end()

tests-extra/tools/dnstest/response.py

@@ -76,13 +76,13 @@ class Response(object):
         if rdata:
             # We work with just one rdata with TTL=0 (this TTL is not used).
             rrset = dns.rdataset.from_text(self.rclass, self.rtype, 0, rdata)
-            ref = list(rrset)[0]
+            ref = str(list(rrset)[0])
 
             # Check answer section if contains reference rdata.
             for data in self.resp.answer:
-                for rdata in data.to_rdataset():
+                for rd in data.to_rdataset():
                     # Compare Rdataset instances.
-                    if rdata == ref:
+                    if str(rd) == ref:
                         # Check CLASS.
                         compare(data.rdclass, self.rclass, "CLASS")
                         # Check TYPE.
@@ -101,13 +101,13 @@ class Response(object):
         if nordata:
             # We work with just one rdata with TTL=0 (this TTL is not used).
             rrset = dns.rdataset.from_text(self.rclass, self.rtype, 0, nordata)
-            ref = list(rrset)[0]
+            ref = str(list(rrset)[0])
 
             # Check answer section if contains reference rdata.
             for data in self.resp.answer:
-                for rdata in data.to_rdataset():
+                for rd in data.to_rdataset():
                     # Compare Rdataset instances.
-                    if rdata == ref:
+                    if str(rd) == ref:
                         set_err("CHECK RDATA")
                         check_log("ERROR: CHECK RDATA")
                         detail_log("!Unwanted data in ANSWER section:")