Re: [docs] [yocto-docs PATCH 13/14] ref-manual/variables: document the PREFERRED_RPROVIDER variable

["Antonin Godard" <antonin.godard@bootlin.com>]

Hi Quentin,

On Tue Dec 17, 2024 at 3:43 PM CET, Quentin Schulz wrote:
> Hi Antonin,
>
> On 12/17/24 10:27 AM, Antonin Godard via lists.yoctoproject.org wrote:
>> This variable is similar to the PREFERRED_PROVIDER variable but it
>> denotes a runtime provider specifically.
>> 
>> Signed-off-by: Antonin Godard <antonin.godard@bootlin.com>
>> ---
>>   documentation/ref-manual/variables.rst | 19 +++++++++++++++++++
>>   1 file changed, 19 insertions(+)
>> 
>> diff --git a/documentation/ref-manual/variables.rst b/documentation/ref-manual/variables.rst
>> index 50cd8948b35f381414837acc9b9e925dc5110779..e0b87c0e5ff8cf7bd2598cbbb184f9aada19d326 100644
>> --- a/documentation/ref-manual/variables.rst
>> +++ b/documentation/ref-manual/variables.rst
>> @@ -6711,6 +6711,25 @@ system and gives an overview of their function and contents.
>>      :term:`PREFERRED_PROVIDERS`
>>         See :term:`bitbake:PREFERRED_PROVIDERS` in the BitBake manual.
>>   
>> +   :term:`PREFERRED_RPROVIDER`
>> +      The :term:`PREFERRED_RPROVIDER` variable works like the
>> +      :term:`PREFERRED_PROVIDER` variable, but it denotes recipes that provide a
>> +      *runtime* component. Runtime providers are declared by recipes that set
>> +      the :term:`RPROVIDES` variable. For example::
>> +
>> +        PREFERRED_RPROVIDER_virtual-x-terminal-emulator = "rxvt-unicode"
>
> Missing a whitespace for the alignment I believe (I believe we're 
> three-whitespace aligned usually?). Ditto for the other code blocks below.
>
>> +
>> +      This statement sets the runtime provider for the X terminal emulator to
>> +      ``rxvt-unicode``. The ``rxvt-unicode`` recipe is a runtime provider of
>> +      this component because it contains the following :term:`RPROVIDES`
>> +      definition::
>> +
>> +        RPROVIDES:${PN} = "virtual-x-terminal-emulator"
>> +
>
> We have to be very careful with the word recipe here. Above, it's the 
> ``rxvt-unicode`` package that is a runtime provider of 
> virtual-x-terminal-emulator, because of the :${PN} override.
>
> I assume PREFERRED_RPROVIDER_virtual-x-terminal-emulator should also 
> contain the name of the package and not the recipe? That I am not 
> entirely sure of though, haven't looked into the implementation of it.

Well... the doc for PREFERRED_PROVIDER _and_ the code refers to these as neither
"packages" or "recipes", but "items". See the doc for PREFERRED_PROVIDER and
https://git.openembedded.org/bitbake/tree/lib/bb/providers.py#n323.

But as you said, the :${PN} override implies that a _package_ RPROVIDES
something, so we understand it the same way.

I will be more precise about this in the v2.


Antonin

-- 
Antonin Godard, Bootlin
Embedded Linux and Kernel engineering
https://bootlin.com