add test for duplicate answers

bdraco · bdraco · commit 71c410e56308 · 2021-07-28T09:59:12.000-05:00
diff --git a/tests/test_handlers.py b/tests/test_handlers.py
@@ -1122,3 +1122,24 @@ async def test_guard_against_low_ptr_ttl():
     assert incoming_answer_normal.ttl == const._DNS_OTHER_TTL
     assert zc.cache.async_get_unique(good_bye_answer) is None
     await aiozc.async_close()
+
+
+@pytest.mark.asyncio
+async def test_duplicate_answers_in_packet():
+    """Ensure we do not throw an exception when there are duplicate records in a packet."""
+    aiozc = AsyncZeroconf(interfaces=['127.0.0.1'])
+    zc = aiozc.zeroconf
+    answer_with_normal_ttl = r.DNSPointer(
+        "myservicelow_tcp._tcp.local.",
+        const._TYPE_PTR,
+        const._CLASS_IN | const._CLASS_UNIQUE,
+        const._DNS_OTHER_TTL,
+        'normal.local.',
+    )
+    response = r.DNSOutgoing(const._FLAGS_QR_RESPONSE)
+    response.add_answer_at_time(answer_with_normal_ttl, 0)
+    response.add_answer_at_time(answer_with_normal_ttl, 0)
+    response.add_answer_at_time(answer_with_normal_ttl, 0)
+    incoming = r.DNSIncoming(response.packets()[0])
+    zc.record_manager.async_updates_from_response(incoming)
+    await aiozc.async_close()
