Re: [PATCH] scripts: checkpatch: Check multiple blank lines when deleting code

[Joe Perches]

On Thu, 2019-02-28 at 13:15 -0500, Alexandre Ghiti wrote:
> By matching only current line starting with '+', we miss the case
> when deleting code makes consecutive blank lines appear: this patch
> then makes it possible to detect this case by also matching current
> line starting with ' ', which is an already existing blank line.
> 
> On the following example, checkpatch --subjective now complains about
> multiple blank lines:
> 
>  static long hugepage_subpool_get_pages(struct hugepage_subpool *spool,
>  {
>  	long ret = delta;
> 
> -	if (!spool)
> -		return ret;
> 
>  	spin_lock(&spool->lock);
> 
> Signed-off-by: Alexandre Ghiti <alex@xxxxxxxx>
> ---
>  scripts/checkpatch.pl | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/scripts/checkpatch.pl b/scripts/checkpatch.pl
[]
> @@ -3298,7 +3298,7 @@ sub process {
>  
>  # check for multiple consecutive blank lines
>  		if ($prevline =~ /^[\+ ]\s*$/ &&
> -		    $line =~ /^\+\s*$/ &&
> +		    $line =~ /^[\+ ]\s*$/ &&
>  		    $last_blank_line != ($linenr - 1)) {
>  			if (CHK("LINE_SPACING",
>  				"Please don't use multiple blank lines\n" . $hereprev) &&

I believe this screws up the --fix option just below this
if the line does not start with +