# HG changeset patch
# User Augie Fackler <raf@durin42.com>
# Date 2017-03-03 19:42:56
# Node ID c920efa9d34b353a51afd75a2ff173fa411004e2
# Parent  dc9842a7017c2e35177e44d5f963161c6a5325dd

config: guard against setconfig specifying unicode values on py3

This was leading to some difficult to trace problems because the
values were set in one place, but then blew up much later in the
program. Exploding violently with an assertion seems reasonable here.

diff --git a/mercurial/config.py b/mercurial/config.py
--- a/mercurial/config.py
+++ b/mercurial/config.py
@@ -13,6 +13,7 @@ import os
 from .i18n import _
 from . import (
     error,
+    pycompat,
     util,
 )
 
@@ -69,6 +70,9 @@ class config(object):
     def items(self, section):
         return self._data.get(section, {}).items()
     def set(self, section, item, value, source=""):
+        if pycompat.ispy3:
+            assert not isinstance(value, str), (
+                'config values may not be unicode strings on Python 3')
         if section not in self:
             self._data[section] = util.sortdict()
         self._data[section][item] = value