Question about 'provides' and emacs packaging
Ken Brown
kbrown@cornell.edu
Wed Oct 6 20:58:43 GMT 2021
On 10/6/2021 4:22 PM, Jon Turney wrote:
> On 06/10/2021 17:23, Jon Turney wrote:
>> On 06/10/2021 13:01, Ken Brown via Cygwin-apps wrote:
>>>
>>> This seems to work, with one caveat. Suppose package P requires feature f,
>>> and packages Q, R, S,... provide f. If the user selects P and one or more of
>>> Q, R, S,..., setup is happy. But if the user simply selects P, then
>>> setup/libsolv will choose among Q, R, S,... the one whose name is
>>> alphabetically first. In the emacs case, this would be emacs-lucid, which is
>>> a stupid default. The default ought to be emacs-nox. So I can make it work
>>> if I call that package emacs-basic instead of emacs-nox.
>>
>> Yeah, I think what's wanted here is for the solver to output a problem with
>> the choices, rather than picking one. I'm not sure how to get it to do that.
>>
>> (Ofc, then we need some UI for picking problem solutions, rather than just
>> always using the default)
>
> Thinking about this some more, that's probably not how it wants to work, since
> just installing emacs-common would then require user interaction to solve the
> problem, rather than just installing emacs-nox as well...
Agreed.
>> (and I'm not sure how we'd encode "emacs-basic" should be the default provider
>> of "emacs-bin" as the input into the solver; presumably there'd by some scheme
>> with weights attached to provide names to set the order rather than alphabetic)
>
> So all that's left is to fix that.
>
> This is discussed somewhat in [1], and it seems that having emacs-common
> suggest: or weak-dep: on emacs-nox would cause that to be the preferred
> provide:r by the solver (in the absence of other provide:ing packages being
> selected or installed)
Yes, that sounds right...
> So I guess we'd need to add something like that to setup.ini and feed that data
> into the solver as well.
...but I'm not sure it's worth the trouble unless other package maintainers
would also have a use for this. As far as emacs is concerned, I'm fine just
changing "emacs-nox" to "emacs-basic" so that it's alphabetically first.
Ken
More information about the Cygwin-apps
mailing list