From 0cd7893e56304dd4b63893969993071dd3818518 Mon Sep 17 00:00:00 2001
From: Vladimir Kotal <vlada@kotalovi.cz>
Date: Thu, 9 Jan 2025 11:55:37 +0100
Subject: [PATCH 1/2] add test for the PUBLISH+UNSUBACK case

---
 tests/test_unsubscribe.py | 45 ++++++++++++++++++++++++++++++++++++++-
 1 file changed, 44 insertions(+), 1 deletion(-)

diff --git a/tests/test_unsubscribe.py b/tests/test_unsubscribe.py
index f7bbb21a..1dfbb856 100644
--- a/tests/test_unsubscribe.py
+++ b/tests/test_unsubscribe.py
@@ -68,6 +68,49 @@ def handle_unsubscribe(client, user_data, topic, pid):
             + [0x6F] * 257
         ),
     ),
+    # UNSUBSCRIBE responded to by PUBLISH followed by UNSUBACK
+    (
+        "foo/bar",
+        bytearray(
+            [
+                0x30,  # PUBLISH
+                0x0C,
+                0x00,
+                0x07,
+                0x66,
+                0x6F,
+                0x6F,
+                0x2F,
+                0x62,
+                0x61,
+                0x72,
+                0x66,
+                0x6F,
+                0x6F,
+                0xB0,  # UNSUBACK
+                0x02,
+                0x00,
+                0x01,
+            ]
+        ),
+        bytearray(
+            [
+                0xA2,  # fixed header
+                0x0B,  # remaining length
+                0x00,
+                0x01,  # message ID
+                0x00,
+                0x07,  # topic length
+                0x66,  # topic
+                0x6F,
+                0x6F,
+                0x2F,
+                0x62,
+                0x61,
+                0x72,
+            ]
+        ),
+    ),
     # use list of topics for more coverage. If the range was (1, 10000), that would be
     # long enough to use 3 bytes for remaining length, however that would make the test
     # run for many minutes even on modern systems, so 1000 is used instead.
@@ -95,7 +138,7 @@ def handle_unsubscribe(client, user_data, topic, pid):
 @pytest.mark.parametrize(
     "topic,to_send,exp_recv",
     testdata,
-    ids=["short_topic", "long_topic", "topic_list_long"],
+    ids=["short_topic", "long_topic", "publish_first", "topic_list_long"],
 )
 def test_unsubscribe(topic, to_send, exp_recv) -> None:
     """

From b8fa023c7e0d94be9f362fa8bdd71c7f11b50484 Mon Sep 17 00:00:00 2001
From: Vladimir Kotal <vlada@kotalovi.cz>
Date: Sun, 19 Jan 2025 10:58:27 +0100
Subject: [PATCH 2/2] no need to check zero byte returned from recv_into()

fixes #157
---
 adafruit_minimqtt/adafruit_minimqtt.py | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/adafruit_minimqtt/adafruit_minimqtt.py b/adafruit_minimqtt/adafruit_minimqtt.py
index b216b16e..75148ed4 100644
--- a/adafruit_minimqtt/adafruit_minimqtt.py
+++ b/adafruit_minimqtt/adafruit_minimqtt.py
@@ -1015,7 +1015,7 @@ def _wait_for_msg(  # noqa: PLR0912, Too many branches
                     return None
                 raise MMQTTException from error
 
-        if res in [None, b"", b"\x00"]:
+        if res in [None, b""]:
             # If we get here, it means that there is nothing to be received
             return None
         pkt_type = res[0] & MQTT_PKT_TYPE_MASK