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/tests/test-hgweb-diffs.t	Sat Dec 16 18:58:02 2017 -0500
+++ b/tests/test-hgweb-diffs.t	Tue Nov 21 17:03:41 2017 +0800
@@ -103,6 +103,7 @@
    <th class="date">date</th>
    <td class="date age">Thu, 01 Jan 1970 00:00:00 +0000</td>
   </tr>
+  
   <tr>
    <th class="author">parents</th>
    <td class="author"></td>
@@ -398,6 +399,7 @@
    <th class="date">date</th>
    <td class="date age">Thu, 01 Jan 1970 00:00:00 +0000</td>
   </tr>
+  
   <tr>
    <th class="author">parents</th>
    <td class="author"></td>