wireproto: introduce pusherr() to deal with "unsynced changes" error

The behaviour between http and ssh still differ:
- the "unsynced changes" is seen as a remote output in the http cases
- but it is correctly seen as a push error for ssh

mercurial/hgweb/protocol.py

@@ -66,3 +66,8 def call(repo, req, cmd):
         sys.stdout, sys.stderr = p.oldio
         req.respond(HTTP_OK, HGTYPE)
         return ['%d\n%s' % (rsp.res, val)]
+    elif isinstance(rsp, wireproto.pusherr):
+        sys.stdout, sys.stderr = p.oldio
+        rsp = '0\n%s\n' % rsp.res
+        req.respond(HTTP_OK, HGTYPE, length=len(rsp))
+        return [rsp]

mercurial/sshserver.py

@@ -79,6 +79,9 class sshserver(object):
         self.sendresponse('')
         self.sendresponse(str(rsp.res))
 
+    def sendpusherror(self, rsp):
+        self.sendresponse(rsp.res)
+
     def serve_forever(self):
         try:
             while self.serve_one():
@@ -92,6 +95,7 class sshserver(object):
         str: sendresponse,
         wireproto.streamres: sendstream,
         wireproto.pushres: sendpushresponse,
+        wireproto.pusherr: sendpusherror,
     }
 
     def serve_one(self):

mercurial/wireproto.py

@@ -142,6 +142,10 class pushres(object):
     def __init__(self, res):
         self.res = res
 
+class pusherr(object):
+    def __init__(self, res):
+        self.res = res
+
 def dispatch(repo, proto, command):
     func, spec = commands[command]
     args = proto.getargs(spec)
@@ -285,7 +289,7 def unbundle(repo, proto, heads):
 
     # fail early if possible
     if not check_heads():
-        return 'unsynced changes'
+        return pusherr('unsynced changes')
 
     # write bundle data to temporary file because it can be big
     fd, tempname = tempfile.mkstemp(prefix='hg-unbundle-')
@@ -298,7 +302,7 def unbundle(repo, proto, heads):
             if not check_heads():
                 # someone else committed/pushed/unbundled while we
                 # were transferring data
-                return 'unsynced changes'
+                return pusherr('unsynced changes')
 
             # push can proceed
             fp.seek(0)