diff mercurial/templates/paper/map @ 35485:1721ce06100a

hgweb: display fate of obsolete changesets

Operations that obsolete changesets store enough metadata to explain what
happened after the fact. One way to get that metadata is showsuccsandmarkers
function, which returns a list of successors of a particular changeset and
appropriate obsolescence markers.

Templates have a set of experimental functions that have names starting with
obsfate. This patch uses some of these functions to interpret output of
succsandmarkers() and produce human-friendly messages that describe what
happened to an obsolete changeset, e.g. "pruned" or "rewritten as
6:3de5eca88c00".

In commonentry(), succsandmarkers property is made callable so it's only
executed on demand; this saves time when changeset is not obsolete, and also in
e.g. /shortlog view, where there are a lot of changesets, but we don't need to
show each and every one in detail.

In spartan theme, succsandmarkers is used instead of the simple "obsolete:
yes", in other themes a new line is added to /rev page.

--- a/mercurial/templates/paper/map	Sat Dec 16 18:58:02 2017 -0500
+++ b/mercurial/templates/paper/map	Tue Nov 21 17:03:41 2017 +0800
@@ -209,6 +209,11 @@
 changelogbranchname = '<span class="branchname">{name|escape}</span> '
 alltags = '{phasetag}{obsoletetag}{instabilities%instabilitytag}{inbranch%changelogbranchname}{branches%changelogbranchhead}{tags%changelogtag}{bookmarks%changelogtag}'
 
+obsfatesuccessors = '{if(successors, ' as ')}{join(successors, ', ')}'
+obsfateverb = '{obsfateverb(successors, markers)}'
+obsfateoperations = '{if(obsfateoperations(markers), ' using {join(obsfateoperations(markers), ', ')}')}'
+obsfateentry = '{obsfateverb}{obsfateoperations}{obsfatesuccessors}'
+
 filediffparent = '
   <tr>
     <th class="parent">parent {rev}:</th>