Re: EXDEV when re-init with --separate-git-dir option

[Junio C Hamano <gitster@pobox.com>]

"Jin, Di" <di_jin@brown.edu> writes:

> We discovered that re-init with option --separate-git-dir will throw
> an EXDEV when the target directory is not on the same file system as
> the original directory.

Yup, it is hitting the limitation of your filesystem.  The code
wants to move the original .git directory together with its contents
to a new place, and it makes a single rename() system call to do so.
When the system cannot do so, you'd get the error message you are
seeing ("fatal: unable to move X to Y").

The code path could probably borrow some code to recursively "copy"
directory from the local "git clone" code path, and then invent a
new code to recursively remove the original ".git", and trigger that
new code when rename() fails.

But at that point, only as a fall-back measure, it might be simpler
and much less error prone to spawn a "mv src dst" as a subprocess
using the run_command() API.

It would make a good bite-sized #leftoverbits project for aspiring
new Git contributors.  Any takers?  ;-)

Thanks.