diff -r f90bb2002bcf -r 4f1144c3c72b mercurial/demandimport.py --- a/mercurial/demandimport.py Sat Aug 08 17:07:34 2015 -0700 +++ b/mercurial/demandimport.py Sat Aug 08 16:13:27 2015 -0700 @@ -139,7 +139,24 @@ # so modern Mercurial code will have level >= 0. if level >= 0: - return _origimport(name, globals, locals, fromlist, level) + # Mercurial's enforced import style does not use + # "from a import b,c,d" or "from .a import b,c,d" syntax. In + # addition, this appears to be giving errors with some modules + # for unknown reasons. Since we shouldn't be using this syntax + # much, work around the problems. + if name: + return _hgextimport(_origimport, name, globals, locals, + fromlist, level) + + mod = _hgextimport(_origimport, name, globals, locals, level=level) + for x in fromlist: + # Missing symbols mean they weren't defined in the module + # itself which means they are sub-modules. + if getattr(mod, x, nothing) is nothing: + setattr(mod, x, + _demandmod(x, mod.__dict__, locals, level=level)) + + return mod # But, we still need to support lazy loading of standard library and 3rd # party modules. So handle level == -1.