# HG changeset patch
# User Pierre-Yves David <pierre-yves.david@octobus.net>
# Date 1508520596 -7200
# Node ID e11e018e83387ede464a9ce0724bbe5ad09affdd
# Parent  9c04bd9280560ac06e43b4033dc849e6fdae9ad4
compat: add an abstraction for 'scmutil.cleanupnodes'

The usage of the function was added in 103244e34a9c but is not compatible with
Mercurial <= 4.2.

diff --git a/hgext3rd/topic/__init__.py b/hgext3rd/topic/__init__.py
--- a/hgext3rd/topic/__init__.py
+++ b/hgext3rd/topic/__init__.py
@@ -778,7 +778,9 @@
         rewrote += 1
 
     # create obsmarkers and move bookmarks
-    scmutil.cleanupnodes(repo, successors, 'changetopics')
+    # XXX we should be creating marker as we go instead of only at the end,
+    # this makes the operations more modulars
+    compat.cleanupnodes(repo, successors, 'changetopics')
 
     # move the working copy too
     wctx = repo[None]
diff --git a/hgext3rd/topic/compat.py b/hgext3rd/topic/compat.py
--- a/hgext3rd/topic/compat.py
+++ b/hgext3rd/topic/compat.py
@@ -7,7 +7,11 @@
 """
 from __future__ import absolute_import
 
-from mercurial import obsolete
+from mercurial import (
+    obsolete,
+    scmutil,
+    util,
+)
 
 getmarkers = None
 successorssets = None
@@ -29,3 +33,15 @@
         ui.pager(cmd)
     except AttributeError:
         pass
+
+def cleanupnodes(repo, replacements, operation, moves=None):
+    # create obsmarkers and move bookmarks
+    # XXX we should be creating marker as we go instead of only at the end,
+    # this makes the operations more modulars
+    if util.safehasattr(scmutil, 'cleanupnodes'):
+        scmutil.cleanupnodes(repo, replacements, 'changetopics',
+                             moves=moves)
+    else:
+        relations = [(repo[o], tuple(repo[n] for n in new))
+                     for (o, new) in replacements.iteritems()]
+        obsolete.createmarkers(repo, relations)