[openib-general] SVN deprecation

[Jeff Squyres]

On Jan 4, 2007, at 6:20 AM, Or Gerlitz wrote:

>> See "svn help <foo>" and the SVN book for more information.
>
> Considering myself as being located somewhere within the ~medium  
> range of the SVN users spectrum I truly think that my questions are  
> not of RTFM type.

Sounds like you just don't want to read the fine documentation.  ;-)

There's a nice overview of browsing a repository's history in the SVN  
book here:

     http://svnbook.red-bean.com/en/1.2/svn-book.html#svn.tour.history

> So let me see i can do it pro actively:
>
> assuming you have used the command
>
> 	$ svn delete some-sub-tree-of-a-repository

Actually, it would be:

svn rm some-tree
svn ci some-tree

That would commit the removal of some-tree at the HEAD at repository  
number N.  Of course, one of the goals of SVN is to maintain an  
accurate history.  So you can always examine the repository at r(N-1)  
(or any prior values of N) to see what subtree looked like at exactly  
those points in time.

Quoting the SVN book:

"Of course, nothing is ever totally deleted from the repository—just  
from the HEAD of the repository. You can get back anything you delete  
by checking out (or updating your working copy) a revision earlier  
than the one in which you deleted it."

> ***and*** left a README at the ancestor directory of this subtree  
> which

Note that leaving a README in the directory has nothing to do with  
the semantics of how SVN works.  I think that this is probably  
obvious, but I just wanted to be precise.  :-)

> says that you have just deleted sub-trees xxx,yyy,zzz etc my work  
> flow to get a checkout of xxx would look like:
>
> 	$ svn co url/of/path/to/ancestor/directory
> 	$ cd /path/to/ancestor/directory
> 	$ read README, learn there was an xxx directory with content XXX
>
> 	$ svn ls xxx -R
> or
> 	$ svn co -r HEAD xxx
> then
> 	$ cd xxx

It's actually simpler than that:

	$ svn co url/of/path/to/ancestor/directory
	$ cd /path/to/ancestor/directory
	$ read README, learn there was an xxx directory with content XXX
	$ svn up -r N

Which updates your current checkout to reflect the state of the  
repository (at that tree) at repository number N (where N is  
assumedly less than the value of N at the HEAD, so you're reverting  
back to an earlier state of the repository, before the stuff that you  
want was deleted).

When navigating the history via "svn up -r N", there's a few complex  
corner cases where the update can fail (by design), but they aren't  
common and can be avoided by doing a fresh checkout of the r number  
that you want:

	$ svn co -r N url/of/path/to/ancestor/directory

-- 
Jeff Squyres
Server Virtualization Business Unit
Cisco Systems