Re: [PATCH] checkpatch: add --fix option for OPEN_BRACE issues

[Joe Perches]

On Thu, 2020-11-19 at 01:52 +0530, Dwaipayan Ray wrote:
> On Thu, Nov 19, 2020 at 1:28 AM Joe Perches <joe@xxxxxxxxxxx> wrote:
> > On Thu, 2020-11-19 at 00:15 +0530, Dwaipayan Ray wrote:
> > > On Thu, Nov 19, 2020 at 12:09 AM Joe Perches <joe@xxxxxxxxxxx> wrote:
> > > > On Thu, 2020-11-19 at 00:03 +0530, Dwaipayan Ray wrote:
> > > > > On Wed, Nov 18, 2020 at 11:44 PM Joe Perches <joe@xxxxxxxxxxx> wrote:
> > > > > > On Wed, 2020-11-18 at 18:10 +0530, Dwaipayan Ray wrote:
> > > > > > > Brace style misuses of the following types are now
> > > > > > > corrected:
> > > > > > []
> > > > > > > diff --git a/scripts/checkpatch.pl b/scripts/checkpatch.pl
> > > > > > []
> > > > > > > @@ -3937,9 +3937,23 @@ sub process {
> > > > > > >                       #print "pre<$pre_ctx>\nline<$line>\nctx<$ctx>\nnext<$lines[$ctx_ln - 1]>\n";
> > > > > > > 
> > > > > > >                       if ($ctx !~ /{\s*/ && defined($lines[$ctx_ln - 1]) && $lines[$ctx_ln - 1] =~ /^\+\s*{/) {
> > > > > > > -                             ERROR("OPEN_BRACE",
> > > > > > > -                                   "that open brace { should be on the previous line\n" .
> > > > > > > -                                     "$here\n$ctx\n$rawlines[$ctx_ln - 1]\n");
> > > > > > > +                             if (ERROR("OPEN_BRACE",
> > > > > > > +                                       "that open brace { should be on the previous line\n" .
> > > > > > > +                                             "$here\n$ctx\n$rawlines[$ctx_ln - 1]\n") &&
> > > > > > > +                                 $fix) {
> > > > > > > +                                     my $line1 = $rawlines[$ctx_ln - 2];
> > > > > > 
> > > > > > How are you sure that in a patch context this line always starts with /^\+/ ?
> > > > > 
> > > > > Hi,
> > > > > I followed it from the other fixes for OPEN_BRACE which were already
> > > > > there. In the patch context if the lines are added then only I think the fix
> > > > > should be triggered. Other instances should not be modified.
> > > > 
> > > > As far as I know there are no existing uses of --fix with OPEN_BRACE.
> > > > 
> > > 
> > > I think you added it via 8d1824780f2f1 ("checkpatch: add --fix option
> > > for a couple OPEN_BRACE misuses")
> > 
> > The difference here is that you are dealing with a $stat context and
> > the existing --fix entries are just for single line fixes.
> > 
> 
> Hi,
> Ya I understand that. Though I am dealing with $stat content,
> I am also directly accessing $rawlines here.
> So I think that should have the proper patch line format, starting
> with + or - or so.
> 
> So in this case if the error is triggered, checking for /^+/ should be done
> becase it would be wrong to fix the others with /^[- ]/
> 
> Is there something else that I am not getting here?

$stat does not include lines that are skipped if the lines start with -

Patch context may be:

line	content

1		func(...
2	-	     original arguments);
3	+	     changed);

where $stat does not include the 'original arguments' changed line

	func(...,
	     changed);

but the $rawlines[] entries are consecutive.

Anyway, this needs to be handled very carefully if handled at all.

I think it's easier to avoid handling these cases and let the
patch submitter fix it manually if appropriate.