Subject: Re: [PATCH 1/2] relative_path should honor dos_drive_prefix

From: Johannes Sixt <[email-masked]>
Date: Tue, 17 Sep 2013 21:32:48 +0200

Am 17.09.2013 10:24, schrieb Jiang Xin:
> I have checked the behavior of UNC path on Windows (msysGit):
> 
> * I can cd to a UNC path:
> 
>     cd //server1/share1/path
> 
> * can cd to other share:
> 
>     cd ../../share2/path
> 
> * and can cd to other server's share:
> 
>     cd ../../../server2/share/path
> 
> That means relative_path(path1, path2) support UNC paths out of the box.
> We only need to check both path1 and path2 are UNC paths, or both not.

Your tests are flawed. You issued the commands in bash, which (or rather
MSYS) does everything for you that you need to make it work. But in
reality it does not, because the system cannot apply .. to //server/share:

$ git ls-remote //srv/public/../repos/his/setups.git
fatal: '//srv/public/../repos/his/setups.git' does not appear to be a
git repository
fatal: Could not read from remote repository.

Please make sure you have the correct access rights
and the repository exists.

even though the repository (and //srv/public, let me assure) exists:

$ git ls-remote //srv/repos/his/setups.git
bea489b0611a72c41f133343fdccbd3e2b9f80b5        HEAD
...

The situation does not change with your latest round (v3).

Please let me suggest not to scratch where there is no itch. ;) Your
round v2 was good enough.

If you really want to check UNC paths, then you must compare two path
components after the the double-slash, not just one.

Furthermore, you should audit all code that references
is_absolute_path(), relative_path(), normalize_path_copy(), and possibly
a few others whether the functions or call sites need improvement.
That's worth a separate patch.

-- Hannes