Ludovic Courtès writes:

> Eric Bavier <ericbavier@gmail.com> skribis:
>
>> Currently, if (@ (guix build utils) wrap-program) is called multiple
>> times for the same file, the original file ends up being overwritten.
>
> OK, you’ve convinced me that this improvement is welcome.

An updated patch is attached.  I changed some of the wording in the
wrap-program docstring to bring it in a bit more in line with the new
behavior.  Let me know if there should be any more adjustments there.  I
also took the liberty of changing "/nix" to "/gnu".  ;)

> It would be ideal if a test in tests/build-utils.scm made sure that
> ‘wrap-program’ uses the right file names when called multiple times,
> but I won’t object if the patch doesn’t have it.

See the new test included in this patch.  Rather than checking for the
file outputs of wrap-program, it checks for correct behavior of the
wrapped program.  I believe this is more consistent with how
wrap-program is used, and doesn't tie the test to the implementation.