Add unit test

server/oauth/tests/test_login.py

@@ -218,3 +218,36 @@ class LoginTests(TestCase):
             self.fail('LoginTests.test_teacher_can_login_with_valid_license: Userdata should not exist')
         except:
             pass
+
+    @patch.object(HepClient, "fetch_eorders", return_value=VALID_TEACHERS_ORDERS)
+    @patch.object(DjangoOAuth2App, "authorize_access_token", return_value=TOKEN)
+    @patch.object(HepClient, "user_details", return_value=ME_DATA)
+    def test_update_of_duration_in_code_MS768(
+        self, user_mock, authorize_mock, orders_mock
+    ):
+        """
+        https://iterativ.atlassian.net/browse/MS-768
+        """
+        response = self._login("/api/oauth/authorize?code=1234")
+
+        user = User.objects.get(email=ME_DATA["email"])
+
+        # user_role_key = user.user_roles.get(user=user).role.key
+
+        # Create a license that expires in 70 days later than duration...
+        # (which is special since the expiration date is set to now+ duration)
+        # This simulates that the duration was changed in the code after the license was created
+
+        current_license: License = (
+            License.objects.filter(licensee=user).order_by("-expire_date").first()
+        )
+        current_license.expire_date = current_license.expire_date + timedelta(days=700)
+        current_license.save()
+        for _ in range(5):
+            response = self._login("/api/oauth/authorize?code=1234")
+
+        # Check that only one new licesnse was created and not one for each login
+        self.assertEqual(License.objects.all().count(), 2)
+
+        self.assertEqual(response.url, f"/{OAUTH_REDIRECT}?state=success")
+        self.assertTrue(self.user.is_authenticated)