--- a/mercurial/util.py Fri Oct 02 23:04:52 2015 -0700
+++ b/mercurial/util.py Sat Oct 03 14:57:24 2015 +0900
@@ -730,6 +730,10 @@
global _hgexecutable
_hgexecutable = path
+def _isstdout(f):
+ fileno = getattr(f, 'fileno', None)
+ return fileno and fileno() == sys.__stdout__.fileno()
+
def system(cmd, environ=None, cwd=None, onerr=None, errprefix=None, out=None):
'''enhanced shell command execution.
run with environment maybe modified, maybe in different dir.
@@ -765,7 +769,7 @@
env = dict(os.environ)
env.update((k, py2shell(v)) for k, v in environ.iteritems())
env['HG'] = hgexecutable()
- if out is None or out == sys.__stdout__:
+ if out is None or _isstdout(out):
rc = subprocess.call(cmd, shell=True, close_fds=closefds,
env=env, cwd=cwd)
else: