fix: fix user cred universe domain issue (#1436)

Author: arithmetic1728

google/oauth2/credentials.py

@@ -180,7 +180,7 @@ def __setstate__(self, d):
         self._rapt_token = d.get("_rapt_token")
         self._enable_reauth_refresh = d.get("_enable_reauth_refresh")
         self._trust_boundary = d.get("_trust_boundary")
-        self._universe_domain = d.get("_universe_domain")
+        self._universe_domain = d.get("_universe_domain") or _DEFAULT_UNIVERSE_DOMAIN
         # The refresh_handler setter should be used to repopulate this.
         self._refresh_handler = None
 

system_tests/secrets.tar.enc

@@ -913,6 +913,17 @@ def test_pickle_and_unpickle(self):
         for attr in list(creds.__dict__):
             assert getattr(creds, attr) == getattr(unpickled, attr)
 
+    def test_pickle_and_unpickle_universe_domain(self):
+        # old version of auth lib doesn't have _universe_domain, so the pickled
+        # cred doesn't have such a field.
+        creds = self.make_credentials()
+        del creds._universe_domain
+
+        unpickled = pickle.loads(pickle.dumps(creds))
+
+        # make sure the unpickled cred sets _universe_domain to default.
+        assert unpickled.universe_domain == "googleapis.com"
+
     def test_pickle_and_unpickle_with_refresh_handler(self):
         expected_expiry = _helpers.utcnow() + datetime.timedelta(seconds=2800)
         refresh_handler = mock.Mock(return_value=("TOKEN", expected_expiry))