children extension: Don't abort when looking at the null revision.

Since 62c56d8f368b revlog.children only returns real children,
so this is no longer a problem.

hgext/children.py

@@ -1,45 +1,41 b''
 # Mercurial extension to provide the 'hg children' command
 #
 # Copyright 2007 by Intevation GmbH <[e-mail]>
 # Author(s):
 # Thomas Arendsen Hein <[e-mail]>
 #
 # This software may be used and distributed according to the terms
 # of the GNU General Public License, incorporated herein by reference.
 
-from mercurial import cmdutil, util
+from mercurial import cmdutil
 from mercurial.i18n import _
-from mercurial.node import nullid
 
 
 def children(ui, repo, file_=None, **opts):
     """show the children of the given or working dir revision
 
     Print the children of the working directory's revisions.
     If a revision is given via --rev, the children of that revision
     will be printed. If a file argument is given, revision in
     which the file was last changed (after the working directory
     revision or the argument to --rev if given) is printed.
     """
     rev = opts.get('rev')
     if file_:
         ctx = repo.filectx(file_, changeid=rev)
     else:
         ctx = repo.changectx(rev)
-    if ctx.node() == nullid:
-        raise util.Abort(_("All non-merge changesets are children of "
-                           "the null revision!"))
 
     displayer = cmdutil.show_changeset(ui, repo, opts)
     for node in [cp.node() for cp in ctx.children()]:
         displayer.show(changenode=node)
 
 
 cmdtable = {
     "children":
         (children,
          [('r', 'rev', '', _('show children of the specified rev')),
           ('', 'style', '', _('display using template map file')),
           ('', 'template', '', _('display with template'))],
          _('hg children [-r REV] [FILE]')),
 }

tests/test-children.out

@@ -1,52 +1,62 b''
 % init
 % no working directory
-abort: All non-merge changesets are children of the null revision!
 % setup
 0 files updated, 0 files merged, 2 files removed, 0 files unresolved
 % hg children at revision 3 (tip)
 0 files updated, 0 files merged, 1 files removed, 0 files unresolved
 % hg children at nullrev (should be 0 and 3)
 2 files updated, 0 files merged, 0 files removed, 0 files unresolved
 % hg children at revision 1 (should be 2)
 changeset:   2:8f5eea5023c2
 user:        test
 date:        Thu Jan 01 00:00:02 1970 +0000
 summary:     2
 
 1 files updated, 0 files merged, 0 files removed, 0 files unresolved
 % hg children at revision 2 (other head)
 % hg children -r null
-abort: All non-merge changesets are children of the null revision!
+changeset:   0:4df8521a7374
+user:        test
+date:        Thu Jan 01 00:00:00 1970 +0000
+summary:     0
+
+changeset:   3:e2962852269d
+tag:         tip
+parent:      -1:000000000000
+user:        test
+date:        Thu Jan 01 00:00:03 1970 +0000
+summary:     3
+
 % hg children -r 0
 changeset:   1:708c093edef0
 user:        test
 date:        Thu Jan 01 00:00:01 1970 +0000
 summary:     1
 
 % hg children -r 1
 changeset:   2:8f5eea5023c2
 user:        test
 date:        Thu Jan 01 00:00:02 1970 +0000
 summary:     2
 
 % hg children -r 2
 % hg children -r 3
 % hg children -r 0 file0 (should be 2)
 changeset:   2:8f5eea5023c2
 user:        test
 date:        Thu Jan 01 00:00:02 1970 +0000
 summary:     2
 
 % hg children -r 1 file0 (should be 2)
 changeset:   2:8f5eea5023c2
 user:        test
 date:        Thu Jan 01 00:00:02 1970 +0000
 summary:     2
 
 1 files updated, 0 files merged, 1 files removed, 0 files unresolved
 % hg children file0 at revision 0 (should be 2)
 changeset:   2:8f5eea5023c2
 user:        test
 date:        Thu Jan 01 00:00:02 1970 +0000
 summary:     2