From b6195d4e77e1309b4b4ecf77508a9ad65b007fcc Mon Sep 17 00:00:00 2001
From: Florian Bruhin <git@the-compiler.org>
Date: Sat, 5 Nov 2016 22:11:52 +0100
Subject: [PATCH] Fix handling of typing.Union with newer Python 3.5 versions

---
 qutebrowser/commands/command.py | 11 +++++++++--
 1 file changed, 9 insertions(+), 2 deletions(-)

diff --git a/qutebrowser/commands/command.py b/qutebrowser/commands/command.py
index 5d98c9166..a2bc3b50d 100644
--- a/qutebrowser/commands/command.py
+++ b/qutebrowser/commands/command.py
@@ -427,9 +427,16 @@ class Command:
         if isinstance(typ, tuple):
             raise TypeError("{}: Legacy tuple type annotation!".format(
                 self.name))
-        elif issubclass(typ, typing.Union):
+        elif type(typ) is type(typing.Union):  # flake8: disable=E721
             # this is... slightly evil, I know
-            types = list(typ.__union_params__)  # pylint: disable=no-member
+            # We also can't use isinstance here because typing.Union doesn't
+            # support that.
+            # pylint: disable=no-member,useless-suppression
+            try:
+                types = list(typ.__union_params__)
+            except AttributeError:
+                types = list(typ.__args__)
+            # pylint: enable=no-member,useless-suppression
             if param.default is not inspect.Parameter.empty:
                 types.append(type(param.default))
             choices = self.get_arg_info(param).choices