[PATCH 1 of 2] wlock: only issue devel warning when actually acquiring the lock

[Pierre-Yves David]

# HG changeset patch
# User Pierre-Yves David <pierre-yves.david at fb.com>
# Date 1428847308 14400
#      Sun Apr 12 10:01:48 2015 -0400
# Node ID 66b327c773f63f0b9f2b00b2126adbf113f1ca36
# Parent  52ff737c63d2b2cb41185549aa9c35bc47317032
wlock: only issue devel warning when actually acquiring the lock

Before this change, any call to 'wlock' after we acquired a 'lock' was issuing a
warning. This is wrong is the 'wlock' have been properly acquired before the
'lock' in a previous call.

We move the warning code to only issue such warnings when we are acquiring the
'wlock' -after- acquiring 'lock'. This is the expected behavior of this warning
from the start.

diff --git a/mercurial/localrepo.py b/mercurial/localrepo.py
--- a/mercurial/localrepo.py
+++ b/mercurial/localrepo.py
@@ -1199,23 +1199,24 @@ class localrepository(object):
 
     def wlock(self, wait=True):
         '''Lock the non-store parts of the repository (everything under
         .hg except .hg/store) and return a weak reference to the lock.
         Use this before modifying files in .hg.'''
+        l = self._wlockref and self._wlockref()
+        if l is not None and l.held:
+            l.lock()
+            return l
+
         if (self.ui.configbool('devel', 'all')
                 or self.ui.configbool('devel', 'check-locks')):
             l = self._lockref and self._lockref()
             if l is not None and l.held:
                 msg = '"lock" taken before "wlock"\n'
                 if self.ui.tracebackflag:
                     util.debugstacktrace(msg, 1)
                 else:
                     self.ui.write_err(msg)
-        l = self._wlockref and self._wlockref()
-        if l is not None and l.held:
-            l.lock()
-            return l
 
         def unlock():
             if self.dirstate.pendingparentchange():
                 self.dirstate.invalidate()
             else:
diff --git a/tests/test-devel-warnings.t b/tests/test-devel-warnings.t
--- a/tests/test-devel-warnings.t
+++ b/tests/test-devel-warnings.t
@@ -13,10 +13,26 @@
   >     tr = repo.transaction('buggy')
   >     lo = repo.lock()
   >     wl = repo.wlock()
   >     wl.release()
   >     lo.release()
+  > 
+  > @command('properlocking', [], '')
+  > def buggylocking(ui, repo):
+  >     """check that reentrance is fine"""
+  >     wl = repo.wlock()
+  >     lo = repo.lock()
+  >     tr = repo.transaction('buggy')
+  >     tr2 = repo.transaction('buggy')
+  >     lo2 = repo.lock()
+  >     wl2 = repo.wlock()
+  >     wl2.release()
+  >     lo2.release()
+  >     tr2.close()
+  >     tr.close()
+  >     lo.release()
+  >     wl.release()
   > EOF
 
   $ cat << EOF >> $HGRCPATH
   > [extensions]
   > buggylocking=$TESTTMP/buggylocking.py
@@ -62,6 +78,7 @@
    */mercurial/dispatch.py:* in _runcommand (glob)
    */mercurial/dispatch.py:* in checkargs (glob)
    */mercurial/dispatch.py:* in <lambda> (glob)
    */mercurial/util.py:* in check (glob)
    $TESTTMP/buggylocking.py:* in buggylocking (glob)
+  $ hg properlocking
   $ cd ..