hg_delta_editor: register copies only if files are unchanged between source and dest Handle copies of items from revision X into revision Y where X is not the parent of Y. This cannot happen in Mercurial because copies always happen between parents and children. A file copy is recorded if: 1- Source and destination revs are in the same branch. 2- The file is unchanged (content, type, removal) through all revisions between destination and source, not including source and destination. Directory copies are registered only if the previous rules apply on all copied items. [1] is there because file copies across branches are meaningless in Mercurial world. We could have tried to remap the source rev to a similar one in the correct branch, but anyway the intent is wrong. [2] is more questionable but I think it's better this way for we live in a non-perfect svn world. In theory, 99% of copies out there should come from the direct parent. But the direct parent is a fuzzy notion when you can have a working directory composed of different directory at different revisions. So we assume that stuff copied from past revisions exactly matching the content of the direct parent revision is really copied from the parent revision. The alternative would be to discard the copy, which would always happen unless people kept updating the working directory after every commit (see tests).

import os

from mercurial import commands
from mercurial import hg

import svncommand
import fetch_command

def svn(ui, repo, subcommand, *args, **opts):
    return svncommand.svncmd(ui, repo, subcommand, *args, **opts)

def svn_fetch(ui, svn_url, hg_repo_path=None, **opts):
    if not hg_repo_path:
        hg_repo_path = hg.defaultdest(svn_url) + "-hg"
        ui.status("Assuming destination %s\n" % hg_repo_path)
    should_update = not os.path.exists(hg_repo_path)
    res = fetch_command.fetch_revisions(ui, svn_url, hg_repo_path, **opts)
    if (res is None or res == 0) and should_update:
        repo = hg.repository(ui, hg_repo_path)
        commands.update(ui, repo, repo['tip'].node())
    return res

commands.norepo += " svnclone"
cmdtable = {
    "svn":
        (svn,
         [('u', 'svn_url', '', 'Path to the Subversion server.'),
          ('', 'stupid', False, 'Be stupid and use diffy replay.'),
          ],
         'hg svn subcommand'),
    "svnclone" :(svn_fetch,
         [('S', 'skipto_rev', '0', 'Skip commits before this revision.'),
          ('', 'stupid', False, 'Be stupid and use diffy replay.'),
          ('T', 'tag_locations', 'tags', 'Relative path to where tags get '
           'stored, as comma sep. values if there is more than one such path.')
         ],
         'hg svn_fetch svn_url, dest'),
}