Re: [PATCH] checkpatch: Look for Kconfig indentation errors

[Krzysztof Kozlowski]

On Tue, 3 Dec 2019 at 16:40, Krzysztof Kozlowski <krzk@xxxxxxxxxx> wrote:
>
> On Thu, 28 Nov 2019 at 17:35, Joe Perches <joe@xxxxxxxxxxx> wrote:
> >
> > On Thu, 2019-11-28 at 11:29 +0200, Jani Nikula wrote:
> > > On Thu, 28 Nov 2019, Krzysztof Kozlowski <krzk@xxxxxxxxxx> wrote:
> > > > Kconfig should be indented with one tab for first level and tab+2 spaces
> > > > for second level.  There are many mixups of this so add a checkpatch
> > > > rule.
> > > >
> > > > Signed-off-by: Krzysztof Kozlowski <krzk@xxxxxxxxxx>
> > >
> > > I agree unifying the indentation is nice, and without something like
> > > this it'll start bitrotting before Krzysztof's done fixing them all... I
> > > think there's been quite a few fixes merged lately.
> > >
> > > I approve of the idea, but I'm clueless about the implementation.
> >
> > I think that a grammar, or a least an array of words
> > that are supposed to start on a tab should be used here.
>
> This won't work for wrong indentation of help text. This is quite
> popular Kconfig indentation violation so worth checking. I can then
> check for:
> 1. any white-space violations before array of Kconfig words - that
> 2. spaces mixed with tab before any text,
> 3. just spaces before any text,
> 4. tab + wrong number of spaces before any text.
>
> It would look like:
> +               if ($realfile =~ /Kconfig/ &&
> +                   (($rawline =~
> /^\+\s+(?:config|menuconfig|choice|endchoice|if|endif|menu|endmenu|source|bool|tristate|prompt|help|---help---|depends|select)\b/
> &&
> +                     $rawline !~ /^\+\t[a-z-]/) ||
> +                    $rawline =~ /^\+\t* +\t+ *[a-zA-Z0-9-]/ ||
> +                    $rawline =~ /^\+\t( |   )[a-zA-Z0-9-]/)) {

This unfortunately fails if help text starts with one of syntax
keywords (e.g. "if"). Isn't this getting over-complicated? The Kconfig
is rather simple:
1. no indentation,
2. one tab,
3. one tab + 2 spaces
4. one tab + 2 spaces + some more spaces (e.g. help text)

Best regards,
Krzysztof