Re: [PATCH] checkpatch: warn if changed lines exceeds a maximum size

[Joe Perches <joe@perches.com>]

On Tue, 2018-01-30 at 15:57 +0000, Brown, Nicholas wrote:
> Changed lines is the total of inserted and deleted lines.
> By default there is no limit, --max-changed-lines may be used to set a
> value. Some users may wish to encourage that patches are split into
> smaller parts using this.
> See Documentation/process/submitting-patches.rst#split-changes

(This patch seems whitespace damaged)

I don't care for this much as is either.

This patch doesn't add help text and it
should probably add a check for
	"if (!$file"
so new files aren't size limited.

Also, it double counts lines that are
added and deleted so doing things like
refactoring a block of code into a new
separate function would potentially trip
this.

> Signed-off-by: Nicholas Brown <nick.brown@att.com>
> ---
>  scripts/checkpatch.pl | 17 +++++++++++++++++
>  1 file changed, 17 insertions(+)
> 
> diff --git a/scripts/checkpatch.pl b/scripts/checkpatch.pl
> index 31031f10fe56..1217d782b6bb 100755
> --- a/scripts/checkpatch.pl
> +++ b/scripts/checkpatch.pl
> @@ -49,6 +49,7 @@ my @ignore = ();
>  my $help = 0;
>  my $configuration_file = ".checkpatch.conf";
>  my $max_line_length = 80;
> +my $max_changed_lines; # undef = no max
>  my $ignore_perl_version = 0;
>  my $minimum_perl_version = 5.10.0;
>  my $min_conf_desc_length = 4;
> @@ -209,6 +210,7 @@ GetOptions(
>         'show-types!'   => \$show_types,
>         'list-types!'   => \$list_types,
>         'max-line-length=i' => \$max_line_length,
> +       'max-changed-lines=i' => \$max_changed_lines,
>         'min-conf-desc-length=i' => \$min_conf_desc_length,
>         'root=s'        => \$root,
>         'summary!'      => \$summary,
> @@ -2165,6 +2167,8 @@ sub process {
>         my $filename = shift;
>  
>         my $linenr=0;
> +       my $inserted_lines_total=0;
> +       my $deleted_lines_total=0;
>         my $prevline="";
>         my $prevrawline="";
>         my $stashline="";
> @@ -2233,6 +2237,14 @@ sub process {
>  
>                 push(@fixed, $rawline) if ($fix);
>  
> +               if ($rawline=~/^\+/) {
> +                 $inserted_lines_total++
> +               }
> +
> +               if ($rawline=~/^-/) {
> +                 $deleted_lines_total++
> +               }
> +
>                 if ($rawline=~/^\+\+\+\s+(\S+)/) {
>                         $setup_docs = 0;
>                         if ($1 =~ m@Documentation/admin-guide/kernel-parameters.rst$@) {
> @@ -2306,6 +2318,11 @@ sub process {
>  
>         $prefix = '';
>  
> +       if (defined $max_changed_lines &&
> +           ($inserted_lines_total+$deleted_lines_total > $max_changed_lines)) {
> +         WARN("MAX_CHANGED_LINES", "please split the change into smaller parts\n");
> +       }
> +
>         $realcnt = 0;
>         $linenr = 0;
>         $fixlinenr = -1;
> -- 
> 2.14.1