# HG changeset patch
# User Bryan O'Sullivan <bos@serpentine.com>
# Date 1177437939 25200
# Node ID 4ddc6d374265374c4abcfa6dd31acfc77b432b85
# Parent  d7ad1e42a3681dab3811d21f75aff2d9b4215a3b
localrepository.status: only acquire wlock if actually needed.

This speeds up the common case of not needing to update the dirstate,
and avoids the need to reload and parse the dirstate "just in case".

diff --git a/mercurial/localrepo.py b/mercurial/localrepo.py
--- a/mercurial/localrepo.py
+++ b/mercurial/localrepo.py
@@ -919,13 +919,10 @@ class localrepository(repo.repository):
             # all the revisions in parent->child order.
             mf1 = mfmatches(node1)
 
+        mywlock = False
+
         # are we comparing the working directory?
         if not node2:
-            if not wlock:
-                try:
-                    wlock = self.wlock(wait=0)
-                except lock.LockException:
-                    wlock = None
             (lookup, modified, added, removed, deleted, unknown,
              ignored, clean) = self.dirstate.status(files, match,
                                                     list_ignored, list_clean)
@@ -942,7 +939,13 @@ class localrepository(repo.repository):
                             modified.append(f)
                         else:
                             clean.append(f)
-                            if wlock is not None:
+                            if not wlock and not mywlock:
+                                mywlock = True
+                                try:
+                                    wlock = self.wlock(wait=0)
+                                except lock.LockException:
+                                    pass
+                            if wlock:
                                 self.dirstate.update([f], "n")
             else:
                 # we are comparing working dir against non-parent
@@ -957,6 +960,9 @@ class localrepository(repo.repository):
                 for f in removed:
                     if f in mf2:
                         del mf2[f]
+
+            if mywlock and wlock:
+                wlock.release()
         else:
             # we are comparing two revisions
             mf2 = mfmatches(node2)