Re: [PATCH] send-email: Ask if a patch should be sent twice

["Ævar Arnfjörð Bjarmason" <avarab@gmail.com>]

On Tue, Jul 30 2019, Dmitry Safonov wrote:

> I was almost certain that git won't let me send the same patch twice,
> but today I've managed to double-send a directory by a mistake:
> 	git send-email --to linux-kernel@vger.kernel.org /tmp/timens/
> 	    --cc 'Dmitry Safonov <0x7f454c46@gmail.com>' /tmp/timens/`
>
> [I haven't noticed that I put the directory twice ^^]
>
> Prevent this shipwreck from happening again by asking if a patch
> is sent multiple times on purpose.
>
> link: https://lkml.kernel.org/r/4d53ebc7-d5b2-346e-c383-606401d19d3a@gmail.com
> Cc: Andrei Vagin <avagin@openvz.org>
> Signed-off-by: Dmitry Safonov <dima@arista.com>
> ---
>  git-send-email.perl | 23 ++++++++++++++++++++++-
>  1 file changed, 22 insertions(+), 1 deletion(-)

There's tests for send-email in t/t9001-send-email.sh. See if what
you're adding can have a test added, seems simple enough in this case.

> diff --git a/git-send-email.perl b/git-send-email.perl
> index 5f92c89c1c1b..0caafc104478 100755
> --- a/git-send-email.perl
> +++ b/git-send-email.perl
> @@ -33,6 +33,7 @@
>  use Net::Domain ();
>  use Net::SMTP ();
>  use Git::LoadCPAN::Mail::Address;
> +use experimental 'smartmatch';

We depend on Perl 5.8, this bumps the requirenment to 5.10. Aside from
that ~~ is its own can of worms in Perl and is best avoided.

>  Getopt::Long::Configure qw/ pass_through /;
>
> @@ -658,6 +659,17 @@ sub is_format_patch_arg {
>  	}
>  }
>
> +sub send_file_twice {
> +	my $f = shift;
> +	$_ = ask(__("Patch $f will be sent twice, continue? [y]/n "),

These cases with a default should have "Y/n", not "y/n". See other
expamples in the file.

> +		default => "y",
> +		valid_re => qr/^(?:yes|y|no|n)/i);
> +	if (/^n/i) {
> +		cleanup_compose_files();
> +		exit(0);

Exit if we have just one of these? More on that later...

> +	}
> +}
> +
>  # Now that all the defaults are set, process the rest of the command line
>  # arguments and collect up the files that need to be processed.
>  my @rev_list_opts;
> @@ -669,10 +681,19 @@ sub is_format_patch_arg {
>  		opendir my $dh, $f
>  			or die sprintf(__("Failed to opendir %s: %s"), $f, $!);
>
> -		push @files, grep { -f $_ } map { catfile($f, $_) }
> +		my @new_files = grep { -f $_ } map { catfile($f, $_) }
>  				sort readdir $dh;
> +		foreach my $nfile (@new_files) {
> +			if ($nfile ~~ @files) {
> +				send_file_twice($nfile);
> +			}

One non-smartmatch idiom for this is:

    my %seen;
    for my $file (@files) {
        if ($seen{$file}++) { ...}
    }

Or:

    my %seen;
    my @dupes = grep { $seen{$_}++ } @files;

> +		}
> +		push @files, @new_files;
>  		closedir $dh;
>  	} elsif ((-f $f or -p $f) and !is_format_patch_arg($f)) {
> +		if ($f ~~ @files) {
> +			send_file_twice($f);
> +		}
>  		push @files, $f;

...but picking up the comment above, I'd expect this to be in the "if
($validate)" block below or something similar, seems like this fits
right in with --validate.

Then you can also ask "do you want to send this set of patches twice
<full list>?".

Now the user is asked a file-at-a-time.

>  	} else {
>  		push @rev_list_opts, $f;