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

[Joe Perches <joe@perches.com>]

On Tue, 2018-01-30 at 19:01 +0000, Nicholas Brown 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

Still whitespace damaged.
Indentations use tabs not 2 spaces.

and another issue below

> Signed-off-by: Nicholas Brown <nick.brown@att.com>
> ---
>  scripts/checkpatch.pl | 19 +++++++++++++++++++
>  1 file changed, 19 insertions(+)
> 
> diff --git a/scripts/checkpatch.pl b/scripts/checkpatch.pl
> index 31031f10fe56..2847109b4def 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;
> @@ -92,6 +93,8 @@ Options:
>    --ignore TYPE(,TYPE2...)   ignore various comma separated message types
>    --show-types               show the specific message type in the output
>    --max-line-length=n        set the maximum line length, if exceeded, warn
> +  --max-changed-lines=n      set the maximum number of changed lines allowed,
> +                             if exceeded, warn. (insertions + deletions)
>    --min-conf-desc-length=n   set the min description length, if shorter, warn
>    --root=PATH                PATH to the kernel tree root
>    --no-summary               suppress the per-file summary
> @@ -209,6 +212,7 @@ 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 +2169,8 @@ 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 +2239,14 @@ sub process {
>  
>  		push(@fixed, $rawline) if ($fix);
>  
> +		if ($rawline=~/^\+/) {
> +		  $inserted_lines_total++

This counts patch header blocks with \+\+\+

> +		}
> +
> +		if ($rawline=~/^-/) {
> +		  $deleted_lines_total++
> +		}

and \-\-\-

> +
>  		if ($rawline=~/^\+\+\+\s+(\S+)/) {
>  			$setup_docs = 0;
>  			if ($1 =~ m@Documentation/admin-guide/kernel-parameters.rst$@) {
> @@ -2306,6 +2320,11 @@ 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;