[XML-SIG] Moving forward

Greg Stein gstein@lyra.org
Thu, 17 Aug 2000 00:10:48 -0700

On Wed, Aug 16, 2000 at 09:58:21PM -0400, Fred L. Drake, Jr. wrote:
> Andrew Kuchling writes:
>  > Why would we lose revision histories?  The v056 tag will get the last
>  > 1.5 version, in case anyone cares, and everything else can continued
>  > to be developed.
>   Depends on how carelessly the changes are made.  ;-)
>   Moving files in CVS is tricking, but using "mv" on the repository
> isn't part of it.
>   The "right" thing to do is to copy the ,v file into the new
> location, remove all the tags on the new file, and then "cvs rm" the
> old file.  That's just really tedious, and requires access to the
> actual repository.  *That's* what I'm proposing -- this keeps the
> development hist as part of the file in the *new* location, which is
> what I mean by "easy access" to the history; you can just get it from
> the current location of the file.

We go through this every six months in the Apache team.

The "right" way to move a file is to "add" it into the new location. Your
checkin message points at the old location. Then "remove" the old.

No mucking with tags. No messing with the repository.

Any time you muck in the repository, you open yourselves to danger. Some of
the pitfalls with the cp/tag-remove are:

1) if the file was in the Attic in the new location, then you've mangled the
   repository: it is illegal to have a file outside *and* inside the attic
2) if somebody pulls files by date, then you'll have an extra/unwanted file
   at the old location. definitely bad.

Really. Never touch the repository. It is just plain bad.


Back to the original point: what is moving? Why did this thread about moving
files even start?

As I saw, we'd be deleting a bunch of crap from the PyXML package. What

And I still disagree with Python 2.0's "replacement" strategy for the "xml"
package with the "_xmlplus" package. How does one access the old files? Does
_xmlplus need to completely replicate everything that appears in 2.0? What
if it replicates the file wrong? Version skew? etc.

No... letting the xmlplus package specify individual pieces is much better
than a wholesale replacement of the module in sys.modules.

[ I'll also point out that sys.modules is a bit shaky itself. I recall a
  couple times during imputil development and discussion, raising the desire
  to totally nuke it. For backwards compat, we certainly can't. But creating
  add'l reliance on it just doesn't feel right.  And no, I don't recall the
  exact issue and don't have the brain cycles right now to go back and
  figger it out. ]


Greg Stein, http://www.lyra.org/