Fix traceback on bad system hgrc files

mercurial/commands.py

@@ -2449,7 +2449,12 b' def dispatch(args):'
     except AttributeError:
         pass
 
-    u = ui.ui()
+    try:
+        u = ui.ui()
+    except util.Abort, inst:
+        sys.stderr.write(_("abort: %s\n") % inst)
+        sys.exit(1)
+
     external = []
     for x in u.extensions():
         def on_exception(Exception, inst):

mercurial/ui.py

@@ -32,10 +32,13 b' class ui:'
         self.interactive = (self.interactive and interactive)
 
     def readconfig(self, fn):
-        try:
-            self.cdata.read(fn)
-        except ConfigParser.ParsingError, inst:
-            raise util.Abort(_("Failed to parse %s\n%s") % (fn, inst))
+        if isinstance(fn, basestring):
+            fn = [fn]
+        for f in fn:
+            try:
+                self.cdata.read(f)
+            except ConfigParser.ParsingError, inst:
+                raise util.Abort(_("Failed to parse %s\n%s") % (f, inst))
 
     def setconfig(self, section, name, val):
         self.overlay[(section, name)] = val