Re: feature-request: git "cp" like there is git mv.

From: Stefan Moch <stefanmoch@mail.de>
Date: Mar 18, 2018, 20:09 UTC
Message-ID: <20180318210908.3ed94777.stefanmoch@mail.de>
In-Reply-To: <xmqqinb87f70.fsf@gitster-ct.c.googlers.com>

* Junio C Hamano <gitster@pobox.com> [2018-02-07T11:49:39-0800]:

Show 20 quoted lines

> Stefan Moch <stefanmoch@mail.de> writes:
> 
> > * Jonathan Nieder <jrnieder@gmail.com> [2017-12-15T17:31:30-0800]:  
> >> This sounds like a reasonable thing to add.  See builtin/mv.c for
> >> how "git mv" works if you're looking for inspiration.
> >> 
> >> cmd_mv in that file looks rather long, so I'd also be happy if
> >> someone interested refactors to break it into multiple
> >> self-contained pieces for easier reading (git mostly follows
> >> https://www.kernel.org/doc/html/latest/process/coding-style.html#functions).  
> >
> > I looked at builtin/mv.c and have a rough idea how to split it
> > up to support both mv and cp commands.
> >
> > But first I noticed and removed a redundant check in cmd_mv,
> > also added a test case to check if mv --dry-run does not move
> > the file.  
> 
> I guess these two patches went unnoticed when posted at the end of
> last year.  Reading them again, I think they are good changes.

Thanks.

Are such redundant checks in general a pattern worth searching for and cleaning up globally? Or is this rather in the category of cleaning up only when noticed?

Show 29 quoted lines

> As a no-op clean-up of a127331c ("mv: allow moving nested
> submodules", 2016-04-19), the attached would also make sense, I
> would think.
> 
> Thanks.
> 
>  builtin/mv.c | 7 ++++---
>  1 file changed, 4 insertions(+), 3 deletions(-)
> 
> diff --git a/builtin/mv.c b/builtin/mv.c
> index 9662804d23..9cb07990fd 100644
> --- a/builtin/mv.c
> +++ b/builtin/mv.c
> @@ -266,10 +266,11 @@ int cmd_mv(int argc, const char **argv, const
> char *prefix) const char *src = source[i], *dst = destination[i];
>  		enum update_mode mode = modes[i];
>  		int pos;
> -		if (show_only || verbose)
> -			printf(_("Renaming %s to %s\n"), src, dst);
> -		if (show_only)
> +		if (show_only) {
> +			if (verbose)
> +				printf(_("Renaming %s to %s\n"),
> src, dst); continue;
> +		}
>  		if (mode != INDEX && rename(src, dst) < 0) {
>  			if (ignore_errors)
>  				continue;
>

As Stefan Beller already noted, this changes the printing behavior: <https://public-inbox.org/git/CAGZ79kbX4uhDpdp0kH=8+5tj_zLWZbtbMUb5WWtOeXWRQz8K3Q@mail.gmail.com/>

See also the output of

    git mv -n
    git mv -n -v
    git mv -v

without your patch:

    $ git mv -n 1 2
    Checking rename of '1' to '2'
    Renaming 1 to 2
    $ git mv -n -v 1 2
    Checking rename of '1' to '2'
    Renaming 1 to 2
    $ git mv -v 1 2
    Renaming 1 to 2

and with your patch:

    $ git mv -n 1 2
    Checking rename of '1' to '2'
    $ git mv -n -v 1 2
    Checking rename of '1' to '2'
    Renaming 1 to 2
    $ git mv -v 1 2

Having different outputs of “git mv -n” and “git mv -n -v” seems odd, but not necessarily wrong. However, “git mv -v” with no output at all, does not what the documentation says:

       -v, --verbose
           Report the names of files as they are moved.