Add dns.resolver.resolve_name(). (#903)

* Add dns.resolver.resolve_name().

* Add missing type annotations.

* Add async resolve_name().

* Replace List[Answer] with HostAnswers.

* Switch addresses_and_families() tuple order

* Fix comment.

2 files changed, 70 insertions, 0 deletions

diff --git a/tests/test_async.py b/tests/test_async.py
index 65f1ed9..52ba2e2 100644
--- a/tests/test_async.py
+++ b/tests/test_async.py
@@ -187,6 +187,48 @@ class AsyncTests(unittest.TestCase):
         dnsgoogle = dns.name.from_text("dns.google.")
         self.assertEqual(answer[0].target, dnsgoogle)
 
+    def testResolveName(self):
+        async def run1():
+            return await dns.asyncresolver.resolve_name("dns.google.")
+
+        answers = self.async_run(run1)
+        seen = set(answers.addresses())
+        self.assertEqual(len(seen), 4)
+        self.assertIn("8.8.8.8", seen)
+        self.assertIn("8.8.4.4", seen)
+        self.assertIn("2001:4860:4860::8844", seen)
+        self.assertIn("2001:4860:4860::8888", seen)
+
+        async def run2():
+            return await dns.asyncresolver.resolve_name("dns.google.", socket.AF_INET)
+
+        answers = self.async_run(run2)
+        seen = set(answers.addresses())
+        self.assertEqual(len(seen), 2)
+        self.assertIn("8.8.8.8", seen)
+        self.assertIn("8.8.4.4", seen)
+
+        async def run3():
+            return await dns.asyncresolver.resolve_name("dns.google.", socket.AF_INET6)
+
+        answers = self.async_run(run3)
+        seen = set(answers.addresses())
+        self.assertEqual(len(seen), 2)
+        self.assertIn("2001:4860:4860::8844", seen)
+        self.assertIn("2001:4860:4860::8888", seen)
+
+        async def run4():
+            await dns.asyncresolver.resolve_name("nxdomain.dnspython.org")
+
+        with self.assertRaises(dns.resolver.NXDOMAIN):
+            self.async_run(run4)
+
+        async def run5():
+            await dns.asyncresolver.resolve_name(dns.reversename.from_address("8.8.8.8"))
+
+        with self.assertRaises(dns.resolver.NoAnswer):
+            self.async_run(run5)
+
     def testCanonicalNameNoCNAME(self):
         cname = dns.name.from_text("www.google.com")
 
diff --git a/tests/test_resolver.py b/tests/test_resolver.py
index c1a97bf..c73451e 100644
--- a/tests/test_resolver.py
+++ b/tests/test_resolver.py
@@ -31,6 +31,7 @@ import dns.quic
 import dns.rdataclass
 import dns.rdatatype
 import dns.resolver
+import dns.reversename
 import dns.tsig
 import dns.tsigkeyring
 import tests.util
@@ -665,6 +666,33 @@ class LiveResolverTests(unittest.TestCase):
         dnsgoogle = dns.name.from_text("dns.google.")
         self.assertEqual(answer[0].target, dnsgoogle)
 
+    def testResolveName(self):
+        answers = dns.resolver.resolve_name("dns.google.")
+        seen = set(answers.addresses())
+        self.assertEqual(len(seen), 4)
+        self.assertIn("8.8.8.8", seen)
+        self.assertIn("8.8.4.4", seen)
+        self.assertIn("2001:4860:4860::8844", seen)
+        self.assertIn("2001:4860:4860::8888", seen)
+
+        answers = dns.resolver.resolve_name("dns.google.", socket.AF_INET)
+        seen = set(answers.addresses())
+        self.assertEqual(len(seen), 2)
+        self.assertIn("8.8.8.8", seen)
+        self.assertIn("8.8.4.4", seen)
+
+        answers = dns.resolver.resolve_name("dns.google.", socket.AF_INET6)
+        seen = set(answers.addresses())
+        self.assertEqual(len(seen), 2)
+        self.assertIn("2001:4860:4860::8844", seen)
+        self.assertIn("2001:4860:4860::8888", seen)
+
+        with self.assertRaises(dns.resolver.NXDOMAIN):
+            dns.resolver.resolve_name("nxdomain.dnspython.org")
+
+        with self.assertRaises(dns.resolver.NoAnswer):
+            dns.resolver.resolve_name(dns.reversename.from_address("8.8.8.8"))
+
     @patch.object(dns.message.Message, "use_edns")
     def testResolveEdnsOptions(self, message_use_edns_mock):
         resolver = dns.resolver.Resolver()