Recommended UI tweaks for depth selection and filtering

I was talking with Karl about the UI around working copy depth selection and
subsequent operations. He explained the status quo as so:

   'svn up' (with no --depth specified) should update your working items,
   preserving their current depth setting.

   'svn up --depth D' is a way to limit the scope of the update data
   delivered by the server. For portions of your working copy shallower
   than D, this means you might get update information that doesn't apply
   to items in your working copy. The result of this will be that
   those areas of your working copy will be changed to now have a depth
   of D. For portions of your working copy already at depth D or deeper,
   only the subset of those items at or shallower than depth D will be
   updated.

In other words, the way to make a shallow part of your working copy less
shallow, you 'svn update' it to a depth value that's ... less shallow. In
order to do the reverse -- aha, well, there's no nice way to do so, just
some hackish workarounds (he didn't describe those).

I proposed the following to Karl, and he seemed to like it.

   Make 'svn up' only ever honor the depth selections of your working
   copy. With no --depth specified, this means, "Update all my stuff."
   With --depth, this becomes a filter applied *after* "Update all my
   stuff", rather like "Update all my stuff that's within the specified
   depth."

   Make 'svn co --depth' the way you tweak a working copy item's
   depth setting to a new value.

In other words, say I want to build a working copy from a project where all
I every really do is mess with the project website and ALLCAPS files. I
checkout the top-level directory with depth immediates:

   $ svn co http://.../project --depth immediates wc
   A wc
   A wc/README
   A wc/LICENSE
   A wc/src
   A wc/www
   A wc/build
   Checked out revision 14.
   $

I then checkout the www directory with depth infinity:
[The following is my ideal syntax ... it might not pass community muster,
though.]

   $ svn co wc/www ## maybe "svn co --depth infinity wc/www"?
   A wc/www/index.html
   A wc/www/logo.png
   Checked out revision 14.
   $

From here on, I can run 'svn up wc' and only ever see (a) changes to the
top-level files, (b) creations of top-level subdirs sans their contents, and
(c) adds/deletes/modifies inside www. If I run 'svn up --depth immediates
wc', though, I won't get the stuff in (c) there.

Later, I need to make a quick fix to the build system:

   $ svn co wc/build
   A wc/build/Makefile.in
   A wc/build/doit.bat
   Checked out revision 18.
   $

I make my tweaks, commit them up, then:

   $ svn co --depth empty wc/build ## wc/build is emptied!
   $

The gist of the idea is that "checkout" becomes not just "make a working
copy where none exists", but "create and depth-adjust working copies".

Unfortunately, I admit that I haven't had the time to fully flesh out these
thoughts. I was primarily concerned about the sort of
dual-role-but-not-quite that 'svn up --depth' was playing in the current
plans, and encouraged by Karl's recognition of that as a potential problem
(and seeming support of what portion of this proposal was baked).

Thoughts?

-- 
C. Michael Pilato <cmpilato@collab.net>
CollabNet   <>   www.collab.net   <>   Distributed Development On Demand