Re: [Feature Request] Better Subversion integration

From: Michael Haggerty <mhagger@alum.mit.edu>
Date: Feb 10, 2008, 16:52 UTC
Message-ID: <47AF2BBF.1060403@alum.mit.edu>
In-Reply-To: <20080210035611.GA2454@atjola.homenet>

Björn Steinbrink wrote:

Show 15 quoted lines

> On 2008.02.09 20:44:59 -0600, Sam Granieri Jr wrote:
>> Right now, git-svn import (or clone) will convert tags and branches as  
>> remote branches.
>> I would like it if git could pick up subversion tags and translate them 
>> as git tags upon importing
> 
> SVN tags aren't like git tags. A "tag" in SVN is just another directory,
> which you can modify at will. Yeah, I know, you _should_ not commit any
> changes to SVN "tags", but shit happens. And once you modify the "tag"
> in SVN, you would have to invalidate the git tag, and finding a commit
> that matches the SVN state of things is probably way too expensive to be
> practical. Maybe some --we-never-mess-up-svn-tag-alike-branches could
> be added to allow git-svn to create teal git tags though? Dunno, I don't
> care much. Shouldn't be too hard to find some shell magic to create
> tags, if one wants them.

Because of the way an SVN repository is stored, it should be cheap to ask SVN whether the contents of a tag in the HEAD revision are identical to the contents at the time the tag was created. If there was any change anywhere under the tag directory, then the node of the tag directory will be different in the two revisions.

For that matter, you could ask SVN for information about the revisions in which the tags/ directory was changed (this is also very cheap), and make sure that none of those changes modified an existing tag. This scan could be done at the beginning of a conversion to determine which tags were handled as pure tags (and therefore convertible as git tags) and which were not (and therefore require more complicated handling).

Michael