Problem: on large repos, it would be useful to be able to do a partial clone and/or checkout
Proposal: add a new file like .hgignore to the .hg/ directory that specifies which files should be ignored for clone/checkout.
[http://www.selenic.com/mercurial/bts/issue105 Issue105 in the BTS] covers partial checkouts and suggests using -X/-I on clone or checkout.
To implement:
- pick a sensible name for this file (BryanOSullivan suggests ignoremissing)
- teach localrepo to use this filtering where appropriate (checkout, pull)
- teach changegroup to choke if someone attempts to pull a changeset from us with a file we don't have
Not to be confused with TrimmingHistory, which trims in the history tree, not the directory tree.