cmdutil: introduce deprecated aliases

cmdutil: introduce deprecated aliases

c8e2d6ed1f9e moved some objects used by Evolve and hence broke the latest
Evolve revision. Next Evolve version will use the new objects when available
but introduce deprecated aliases so users using older version of Evolve won't
have a broken Evolve extension.

Differential Revision: https://phab.mercurial-scm.org/D2023

--- a/mercurial/cmdutil.py	Mon Feb 05 18:39:41 2018 +0800
+++ b/mercurial/cmdutil.py	Sun Feb 04 12:00:17 2018 +0100
@@ -3124,3 +3124,23 @@
     if after[1]:
         hint = after[0]
     raise error.Abort(_('no %s in progress') % task, hint=hint)
+
+class changeset_printer(logcmdutil.changesetprinter):
+
+    def __init__(self, ui, *args, **kwargs):
+        msg = ("'cmdutil.changeset_printer' is deprecated, "
+               "use 'logcmdutil.logcmdutil'")
+        ui.deprecwarn(msg, "4.6")
+        super(changeset_printer, self).__init__(ui, *args, **kwargs)
+
+def displaygraph(ui, *args, **kwargs):
+    msg = ("'cmdutil.displaygraph' is deprecated, "
+           "use 'logcmdutil.displaygraph'")
+    ui.deprecwarn(msg, "4.6")
+    return logcmdutil.displaygraph(ui, *args, **kwargs)
+
+def show_changeset(ui, *args, **kwargs):
+    msg = ("'cmdutil.show_changeset' is deprecated, "
+           "use 'logcmdutil.changesetdisplayer'")
+    ui.deprecwarn(msg, "4.6")
+    return logcmdutil.changesetdisplayer(ui, *args, **kwargs)