Re: [PATCH] dt-bindings: Whitespace clean-ups in schema files

[Rob Herring <robh@kernel.org>]

On Wed, Aug 12, 2020 at 4:32 PM Joe Perches <joe@perches.com> wrote:
>
> On Wed, 2020-08-12 at 14:36 -0600, Rob Herring wrote:
> > Clean-up incorrect indentation, extra spaces, long lines, and missing
> > EOF newline in schema files. Most of the clean-ups are for list
> > indentation which should always be 2 spaces more than the preceding
>                                      ^
> > keyword.

keyword is the key part...

> []
> > diff --git a/Documentation/devicetree/bindings/arm/arm,integrator.yaml b/Documentation/devicetree/bindings/arm/arm,integrator.yaml
> > index 192ded470e32..f0daf990e077 100644
> > --- a/Documentation/devicetree/bindings/arm/arm,integrator.yaml
> > +++ b/Documentation/devicetree/bindings/arm/arm,integrator.yaml
> > @@ -67,9 +67,9 @@ patternProperties:
> >        compatible:
> >          items:
> >            - enum:
> > -            - arm,integrator-ap-syscon
> > -            - arm,integrator-cp-syscon
> > -            - arm,integrator-sp-syscon
> > +              - arm,integrator-ap-syscon
> > +              - arm,integrator-cp-syscon
> > +              - arm,integrator-sp-syscon
>
> Confused a bit here.
>           - enum:
>         10 spaces to dash
> old line:
>             - arm,integrator-ap-syscon
>         12 spaces to dash
> new line:
>               - arm,integrator-ap-syscon
>         14 spaces to dash
>
> Is it supposed to be 2 spaces more than the preceding line
> or 4 more?

If the preceding line is a list entry (i.e. starts with '-'), then
it's 4 more spaces. It's always 2 more spaces than the preceding
keyword start (aka json-schema vocabulary).

Arguably, this style is a bit inconsistent in that the '-' counts
toward as indentation of the current line, but not the preceding line.
However, I think this style is a bit less error prone and easier to
review. With the other style (always N more spaces) it's harder to
distinguish lists vs. dicts. For example, you can have something like
this:

- key:
  - foo
  - bar

- key:
    foo
    bar

- key:
  - foo
    bar

All 3 of these could be valid. Which one was intended? (Can't really
tell here, but you can with actual DT schema.)

Rob