[PATCH RFC stateful-chg] dispatch: make request accept additional reposetups

[Jun Wu]

# HG changeset patch
# User Jun Wu <quark at fb.com>
# Date 1493527187 25200
#      Sat Apr 29 21:39:47 2017 -0700
# Node ID 9b7eae7f7d613762884ac4880be74b23fe4c7415
# Parent  37bcb4665529f5cc59b8dffb1014ac0cab37492c
# Available At https://bitbucket.org/quark-zju/hg-draft
#              hg pull https://bitbucket.org/quark-zju/hg-draft -r 9b7eae7f7d61
dispatch: make request accept additional reposetups

chg needs special logic around repo object creation (like, collecting and
reporting repo path to the master server). Adding "reposetup" to
dispatch.request seems to be an easy and reasonably clean way to allow that.

diff --git a/mercurial/dispatch.py b/mercurial/dispatch.py
--- a/mercurial/dispatch.py
+++ b/mercurial/dispatch.py
@@ -49,5 +49,5 @@ from . import (
 class request(object):
     def __init__(self, args, ui=None, repo=None, fin=None, fout=None,
-                 ferr=None):
+                 ferr=None, prereposetups=None):
         self.args = args
         self.ui = ui
@@ -59,4 +59,8 @@ class request(object):
         self.ferr = ferr
 
+        # reposetups which run before extensions, useful for chg to pre-fill
+        # low-level repo state (for example, changelog) before extensions.
+        self.prereposetups = prereposetups or []
+
     def _runexithandlers(self):
         exc = None
@@ -876,5 +880,6 @@ def _dispatch(req):
             else:
                 try:
-                    repo = hg.repository(ui, path=path)
+                    repo = hg.repository(ui, path=path,
+                                         presetupfuncs=req.prereposetups)
                     if not repo.local():
                         raise error.Abort(_("repository '%s' is not local")
diff --git a/mercurial/hg.py b/mercurial/hg.py
--- a/mercurial/hg.py
+++ b/mercurial/hg.py
@@ -149,8 +149,10 @@ def openpath(ui, path):
 wirepeersetupfuncs = []
 
-def _peerorrepo(ui, path, create=False):
+def _peerorrepo(ui, path, create=False, presetupfuncs=None):
     """return a repository object for the specified path"""
     obj = _peerlookup(path).instance(ui, path, create)
     ui = getattr(obj, "ui", ui)
+    for f in presetupfuncs or []:
+        f(ui, obj)
     for name, module in extensions.extensions(ui):
         hook = getattr(module, 'reposetup', None)
@@ -162,7 +164,7 @@ def _peerorrepo(ui, path, create=False):
     return obj
 
-def repository(ui, path='', create=False):
+def repository(ui, path='', create=False, presetupfuncs=None):
     """return a repository object for the specified path"""
-    peer = _peerorrepo(ui, path, create)
+    peer = _peerorrepo(ui, path, create, presetupfuncs=presetupfuncs)
     repo = peer.local()
     if not repo: