[PATCH 5 of 8] pager: use super class's _runpager if possible

[Jun Wu]

# HG changeset patch
# User Jun Wu <quark at fb.com>
# Date 1484002766 -28800
#      Tue Jan 10 06:59:26 2017 +0800
# Node ID 24ebef0f19843c6b1b8fbf32d99a7e8dba2fb734
# Parent  483eabc8ccbbdfabed7f0f0abd74fb131adcd3c3
# Available At https://bitbucket.org/quark-zju/hg-draft
#              hg pull https://bitbucket.org/quark-zju/hg-draft -r 24ebef0f1984
pager: use super class's _runpager if possible

The ui class is currently pagerui(chgui(ui)), so chgui's _runpager will be
overrided by pagerui. Detect it and use chgui's _runpager, in pager.py.

In the future, when pager is moved to core, pagerui will no longer exist and
ui.py has _runpager implemented directly, and we can just call ui._runpager
without any check.

diff --git a/hgext/pager.py b/hgext/pager.py
--- a/hgext/pager.py
+++ b/hgext/pager.py
@@ -121,5 +121,6 @@ def uisetup(ui):
     class pagerui(ui.__class__):
         def _runpager(self, pagercmd):
-            _runpager(self, pagercmd)
+            runpager = getattr(super(pagerui, self), '_runpager', _runpager)
+            runpager(self, pagercmd)
 
     ui.__class__ = pagerui