Re: [PATCH] cooker.py: allow dangling bbappends if explicitly whitelisted

[Patrick Ohly <patrick.ohly@intel.com>]

On Thu, 2017-05-25 at 08:50 -0700, Christopher Larson wrote:
> 
> On Mon, May 22, 2017 at 3:50 AM, Patrick Ohly <patrick.ohly@intel.com>
> wrote:
>         Having a .bbappend without corresponding .bb file triggers an
>         error or
>         at least warning, depending on the global
>         BB_DANGLINGAPPENDS_WARNONLY.
>         
>         Some layers (for example, meta-freescale) avoid that message
>         by only
>         adding .bbappends to the BBFILES when the layers they apply to
>         are
>         present. Others (like intel-iot-refkit) avoid such .bbappends
>         by
>         falling back to global assignments with _pn-<recipe> as
>         override. Both
>         is complicated.
>         
>         Now the warning code checks BBAPPENDS_DANGLING_WHITELIST and
>         ignores
>         all bbappends which match a file pattern in that list. This is
>         an
>         easier way to have bbappends which may or may not apply to an
>         existing recipe.
> 
> IMHO this makes it too easy to miss legitimate problems. By adding
> them only when the layers are present, you ensure that if that layer
> removes the recipe you’re appending, you’ll immediately know it. This
> hides such actual problems by suppressing for all optional appends
> across the board.

I understand that it is a double-edged sword. It's meant for layer
maintainers who know what they are doing. If a layer maintainer prefers
to be warned about missing recipes, they can simply ignore the whitelist
feature. Layer maintainers who use it need to ensure that they have
tests in place which will fail when the bbappend is no longer used.

-- 
Best Regards, Patrick Ohly

The content of this message is my personal opinion only and although
I am an employee of Intel, the statements I make here in no way
represent Intel's position on the issue, nor am I authorized to speak
on behalf of Intel on this matter.