From 9c4603e4a19d4c70b446e010c64ce9cb64313db1 Mon Sep 17 00:00:00 2001
From: Joe Haines <hello@joehaines.co.uk>
Date: Fri, 17 May 2024 10:28:17 +0100
Subject: [PATCH] Avoid reading `__code__` if it doesn't exist

---
 bugsnag/configuration.py  |  6 +++++-
 bugsnag/sessiontracker.py |  5 ++++-
 tests/test_client.py      | 17 +++++++++++++++++
 3 files changed, 26 insertions(+), 2 deletions(-)

diff --git a/bugsnag/configuration.py b/bugsnag/configuration.py
index f96752b8..114de35b 100644
--- a/bugsnag/configuration.py
+++ b/bugsnag/configuration.py
@@ -279,7 +279,11 @@ def delivery(self, value):
             # this should be made mandatory in the next major release
             if (
                 hasattr(value, 'deliver_sessions') and
-                callable(value.deliver_sessions)
+                callable(value.deliver_sessions) and
+                # Mock objects don't allow accessing or mocking '__code__' so
+                # ensure it exists before attempting to read it
+                # __code__ should always be present in a real delivery object
+                hasattr(value.deliver_sessions, '__code__')
             ):
                 parameter_names = value.deliver_sessions.__code__.co_varnames
 
diff --git a/bugsnag/sessiontracker.py b/bugsnag/sessiontracker.py
index edb8bf26..adc31537 100644
--- a/bugsnag/sessiontracker.py
+++ b/bugsnag/sessiontracker.py
@@ -139,7 +139,10 @@ def __deliver(self, sessions: List[Dict], asynchronous=True):
 
             deliver = self.config.delivery.deliver_sessions
 
-            if 'options' in deliver.__code__.co_varnames:
+            if (
+                hasattr(deliver, '__code__') and
+                'options' in deliver.__code__.co_varnames
+            ):
                 try:
                     post_delivery_callback = self._request_tracker.new_request()
 
diff --git a/tests/test_client.py b/tests/test_client.py
index f01b8589..2b7233fc 100644
--- a/tests/test_client.py
+++ b/tests/test_client.py
@@ -18,6 +18,7 @@
     FeatureFlag
 )
 
+from bugsnag.delivery import Delivery
 import bugsnag.legacy as legacy
 from tests.utils import (
     BrokenDelivery,
@@ -124,6 +125,22 @@ def deliver(foo, config, payload, options={}):
         self.assertTrue(self.called)
         del self.called
 
+    # test for a regression caused by reading '__code__', which does not exist
+    # on Mock objects, nor can it be mocked
+    # see: https://github.com/bugsnag/bugsnag-python/commit/77e11747c293ba715bc764d17b49fb32918c030a#r142130768
+    def test_delivery_can_be_mocked(self):
+        delivery = Mock(spec=Delivery)
+
+        client = Client(delivery=delivery, api_key='abc')
+        client.notify(Exception('Oh no'))
+
+        assert delivery.deliver.call_count == 1
+
+        client.session_tracker.start_session()
+        client.session_tracker.send_sessions()
+
+        assert delivery.deliver_sessions.call_count == 1
+
     # Capture
 
     def test_notify_capture(self):