# HG changeset patch
# User Siddharth Agarwal <sid0@fb.com>
# Date 1444081079 25200
# Node ID 366d489295ca7293887c4b9079620d8421616002
# Parent  f0d730efb02f2476f1cd1127a3f0a56107097b96
scmutil: add a way for a repo's wlock to be inherited by a subprocess

This is part of a series that will allow locks to be inherited by subprocesses
in limited circumstances.

In the future, we'll call this for custom merge drivers.

diff -r f0d730efb02f -r 366d489295ca mercurial/scmutil.py
--- a/mercurial/scmutil.py	Mon Oct 05 14:34:52 2015 -0700
+++ b/mercurial/scmutil.py	Mon Oct 05 14:37:59 2015 -0700
@@ -1158,3 +1158,12 @@
     with lock.inherit() as locker:
         environ[envvar] = locker
         return repo.ui.system(cmd, environ=environ, *args, **kwargs)
+
+def wlocksub(repo, cmd, *args, **kwargs):
+    """run cmd as a subprocess that allows inheriting repo's wlock
+
+    This can only be called while the wlock is held. This takes all the
+    arguments that ui.system does, and returns the exit code of the
+    subprocess."""
+    return _locksub(repo, repo.currentwlock(), 'HG_WLOCK_LOCKER', cmd, *args,
+                    **kwargs)