Re: [Monotone-devel] 3 proposed changes to manifest/changeset format

[Matt Johnston]

On Tue, May 10, 2005 at 03:26:40AM -0700, Nathaniel Smith wrote:
> Some smaller changes are in the offing, though:
> 
> - First-class directory support 

If it'll fix dir dropping etc, sounds sane. Would this have
consequences for making the root directory renamable? I'd
like to seen renamable root directories eventually getting
supported, as it seems to provide a convenient way to bring
third party branches into a project (ie "/" of the
hypothetical org.sqlite.sqlite branch gets renamed to
"sqlite/" when propagated to the net.venge.monotone branch). 

> - Patches on delete_file: Currently, there's an assymmetry in the
> change_set format -- add_file "foo" is accompanied by patch "foo" from
> [] to [<initial hash>].  delete_file "foo", on the other hand, is not
> accompanied by a patch "foo" from [<final hash>] to [].  The reason
> for this is that such a hash would be redundant, but I think it's a
> decision worth revisiting.

My gut feeling is that having the explicit patch to [] is
likely to increase the chances of triggering invariants in
edge/untested cases for change_set.cc, which is a good thing.

> - Attributes in manifests: this is a speculative idea, raised for
> discussion -- if we use basic_io for manifests, it becomes pretty
> straightforward to include file attributes (like .mt-attrs currently
> stores) directly into the manifest, if we want to.  Presumably this
> would also involve adding "set_attr" and "delete_attr" type operations
> to changesets.

One issue here is that without changes to the revision
format, it'd be possible for a revision to have no changeset
information yet differing old_ and new_ manifests, when only
the attributes are altered?

Matt