chgserver: make _renewui load repo and command line configs

Before this patch, there is no way to load repo config in chgserver. This
patch revised _renewui to let it load repo config and take command line
flags passed into consideration.

The _renewui logic is not ideal at present because it's very tricky to know
what should copy and what should not from the old ui object to the new one.
This is partially because the current ui and config object design is not
ideal. In the future, we may want to avoid all ui or config copies.

hgext/chgserver.py

@@ -180,17 +180,35 b' def _newchgui(srcui, csystem):'
 
     return chgui(srcui)
 
-def _renewui(srcui):
+def _renewui(srcui, args=None):
+    if not args:
+        args = []
+
     newui = srcui.__class__()
     for a in ['fin', 'fout', 'ferr', 'environ']:
         setattr(newui, a, getattr(srcui, a))
     if util.safehasattr(srcui, '_csystem'):
         newui._csystem = srcui._csystem
+
+    # load wd and repo config, copied from dispatch.py
+    cwds = dispatch._earlygetopt(['--cwd'], args)
+    cwd = cwds and os.path.realpath(cwds[-1]) or None
+    rpath = dispatch._earlygetopt(["-R", "--repository", "--repo"], args)
+    path, newui = dispatch._getlocal(newui, rpath, wd=cwd)
+
+    # internal config: extensions.chgserver
+    # copy it. it can only be overrided from command line.
+    newui.setconfig('extensions', 'chgserver',
+                    srcui.config('extensions', 'chgserver'), '--config')
+
+    # command line args
+    dispatch._parseconfig(newui, dispatch._earlygetopt(['--config'], args))
+
     # stolen from tortoisehg.util.copydynamicconfig()
     for section, name, value in srcui.walkconfig():
         source = srcui.configsource(section, name)
-        if ':' in source:
-            # path:line
+        if ':' in source or source == '--config':
+            # path:line or command line
             continue
         if source == 'none':
             # ui.configsource returns 'none' by default