dispatch: use the request to store the ui object

dispatch: use the request to store the ui object

and check if we got one before creating.

note that the contents of the ui object might change after
dispatch() returns (by options passed through --config for example),
to ensure it doesn't, pass a copy() of it.

--- a/mercurial/dispatch.py	Thu May 26 00:44:11 2011 +0300
+++ b/mercurial/dispatch.py	Thu May 26 00:53:23 2011 +0300
@@ -12,8 +12,9 @@
 import ui as uimod
 
 class request(object):
-    def __init__(self, args):
+    def __init__(self, args, ui=None):
         self.args = args
+        self.ui = ui
 
 def run():
     "run the command in sys.argv"
@@ -22,9 +23,10 @@
 def dispatch(req):
     "run the command specified in req.args"
     try:
-        u = uimod.ui()
+        if not req.ui:
+            req.ui = uimod.ui()
         if '--traceback' in req.args:
-            u.setconfig('ui', 'traceback', 'on')
+            req.ui.setconfig('ui', 'traceback', 'on')
     except util.Abort, inst:
         sys.stderr.write(_("abort: %s\n") % inst)
         if inst.hint:
@@ -37,12 +39,13 @@
         else:
             sys.stderr.write(_("hg: parse error: %s\n") % inst.args[0])
         return -1
-    return _runcatch(u, req)
+    return _runcatch(req)
 
-def _runcatch(ui, req):
+def _runcatch(req):
     def catchterm(*args):
         raise error.SignalInterrupt
 
+    ui = req.ui
     try:
         for name in 'SIGBREAK', 'SIGHUP', 'SIGTERM':
             num = getattr(signal, name, None)
@@ -59,7 +62,7 @@
                         "type c to continue starting hg or h for help\n"))
                 pdb.set_trace()
             try:
-                return _dispatch(ui, req)
+                return _dispatch(req)
             finally:
                 ui.flush()
         except:
@@ -490,8 +493,10 @@
     os.chdir(cwd)
 
 _loaded = set()
-def _dispatch(ui, req):
+def _dispatch(req):
     args = req.args
+    ui = req.ui
+
     shellaliasfn = _checkshellalias(ui, args)
     if shellaliasfn:
         return shellaliasfn()
@@ -602,7 +607,7 @@
                     guess = repos[0]
                     if guess and repos.count(guess) == len(repos):
                         req.args = ['--repository', guess] + fullargs
-                        return _dispatch(ui, req)
+                        return _dispatch(req)
                 if not path:
                     raise error.RepoError(_("no repository found in %r"
                                             " (.hg not found)") % os.getcwd())