From 4d111d2921dc3473488d254fd638c7e040cde36a Mon Sep 17 00:00:00 2001 From: Paul Kehrer Date: Fri, 11 Mar 2016 22:38:00 -0400 Subject: make multibackend error with an empty list. fixes #2717 --- src/cryptography/hazmat/backends/multibackend.py | 7 +++++++ 1 file changed, 7 insertions(+) (limited to 'src') diff --git a/src/cryptography/hazmat/backends/multibackend.py b/src/cryptography/hazmat/backends/multibackend.py index 65f18531..95382450 100644 --- a/src/cryptography/hazmat/backends/multibackend.py +++ b/src/cryptography/hazmat/backends/multibackend.py @@ -28,6 +28,13 @@ class MultiBackend(object): name = "multibackend" def __init__(self, backends): + if len(backends) == 0: + raise ValueError( + "Multibackend cannot be initialized with no backends. If you " + "are seeing this error when trying to use default_backend " + "please try uninstalling and reinstalling cryptography." + ) + self._backends = backends def _filtered_backends(self, interface): -- cgit v1.2.3