Re: [PATCH] staging: rtl8723au: Fixes unnecessary return warning

[Joe Perches]

On Sat, 2016-01-30 at 23:02 +1100, Julian Calaby wrote:
> Hi Bhakti,
> 
> On Sat, Jan 30, 2016 at 5:53 PM, Bhakti Priya  wrote:
> > Hi,
> > 
> > Thank you for your reply. I've just sent version 2 of the patch with
> > the blank lines removed.
> > I will be happy to extend checkpatch.pl. As suggested by you, I am
> > trying to detect such blank lines in a line removal patch by checking
> > if the line above the deleted line was a blank line and the line
> > following the deleted line had a closing brace.
> > Can you please guide me and let me know if I am headed in the right direction.
> 
> As I understand it, the algorithm needs to work like this:
> 1. For each patch hunk:
> 2. Filter out all lines that match /^-/
> 3. Remove the first character (" " or "+")
> 4. Normalise EOL characters: s/\r\n?/\n/
> 5. Over the entire hunk, find any case that matches
> /({|\n)\s*\n\s*(\n|})/ where \s matches all space characters except
> \n.
> 6. Report the middle line the preceding regular expression matches to the user.
> 
> I'm confident I can write it as a shell script, but I don't know
> enough Perl to add that test to checkpatch.pl

That's basically what the $prevline variable in checkpatch does.
Likely it's enough to check that.
Perhaps Andy Whitcroft knows.