# HG changeset patch
# User Gregory Szorc <gregory.szorc@gmail.com>
# Date 2015-06-28 00:31:06
# Node ID 5d0847cd158741975598a29eedad1327af41fd1f
# Parent  fa1f045297753a1f2caf013cecfcd5fa68300ccb

demandimport: support importing builtins for Python 3

__builtin__ was renamed to builtins in Python 3. If importing
__builtin__ fails, fall back to importing builtins in order to support
Python 3.

diff --git a/mercurial/demandimport.py b/mercurial/demandimport.py
--- a/mercurial/demandimport.py
+++ b/mercurial/demandimport.py
@@ -26,7 +26,12 @@ These imports will not be delayed:
 
 import os, sys
 from contextlib import contextmanager
-import __builtin__ as builtins
+
+# __builtin__ in Python 2, builtins in Python 3.
+try:
+    import __builtin__ as builtins
+except ImportError:
+    import builtins
 
 _origimport = __import__