fix locate broken since 63799b01985c

- fix the keyword arguments for walk in commands.locate
- implement 'hg locate -r <rev>'
- add a test for 'hg locate'

tests/test-locate

@@ -0,0 +1,20 b''
+#!/bin/sh
+#
+mkdir t
+cd t
+hg init
+echo 0 > a
+echo 0 > b
+hg ci -A -m m -d "0 0"
+touch nottracked
+hg locate a
+hg locate NONEXISTENT
+hg locate
+hg rm a
+hg ci -m m -d "0 0"
+hg locate a
+hg locate NONEXISTENT
+hg locate
+hg locate -r 0 a
+hg locate -r 0 NONEXISTENT
+hg locate -r 0

tests/test-locate.out

@@ -0,0 +1,13 b''
+adding a
+adding b
+a
+NONEXISTENT: No such file or directory
+a
+b
+a: No such file or directory
+NONEXISTENT: No such file or directory
+b
+a
+NONEXISTENT: No such file in rev 9e1684505872
+a
+b

mercurial/commands.py

@@ -1531,9 +1531,15 b' def locate(ui, repo, *pats, **opts):'
     that contain white space as multiple filenames.
     """
     end = opts['print0'] and '\0' or '\n'
+    rev = opts['rev']
+    if rev:
+        node = repo.lookup(rev)
+    else:
+        node = None
 
-    for src, abs, rel, exact in walk(repo, pats, opts, '(?:.*/|)'):
-        if repo.dirstate.state(abs) == '?':
+    for src, abs, rel, exact in walk(repo, pats, opts, node=node,
+                                     head='(?:.*/|)'):
+        if not node and repo.dirstate.state(abs) == '?':
             continue
         if opts['fullpath']:
             ui.write(os.path.join(repo.root, abs), end)