diff mercurial/configitems.py @ 40636:054d0fcba2c4

commandserver: add experimental option to use separate message channel

This is loosely based on the idea of the TortoiseHg's pipeui extension,
which attaches ui.label to message text so the command-server client can
capture prompt text, for example.

https://bitbucket.org/tortoisehg/thg/src/4.7.2/tortoisehg/util/pipeui.py

I was thinking that this functionality could be generalized to templating,
but changed mind as doing template stuff would be unnecessarily complex.
It's merely a status message, a simple serialization option should suffice.

Since this slightly changes the command-server protocol, it's gated by a
config knob. If the config is enabled, and if it's supported by the server,
"message-encoding: <name>" is advertised so the client can stop parsing
'o'/'e' channel data and read encoded messages from the 'm' channel. As we
might add new message encodings in future releases, client can specify a list
of encoding names in preferred order.

This patch includes 'cbor' encoding as example. Perhaps, 'json' should be
supported as well.

--- a/mercurial/configitems.py	Wed Nov 07 22:37:51 2018 +0900
+++ b/mercurial/configitems.py	Sun Jan 18 18:49:59 2015 +0900
@@ -173,6 +173,9 @@
 coreconfigitem('cmdserver', 'log',
     default=None,
 )
+coreconfigitem('cmdserver', 'message-encodings',
+    default=list,
+)
 coreconfigitem('color', '.*',
     default=None,
     generic=True,