[R-pkg-devel] Handling Not-Always-Needed Dependencies?

[Duncan Murdoch]

On 03/08/2016 11:17 AM, Dirk Eddelbuettel wrote:
>
> On 3 August 2016 at 16:21, Uwe Ligges wrote:
> |
> |
> | On 03.08.2016 16:14, Dirk Eddelbuettel wrote:
> | >
> | > On 3 August 2016 at 16:00, Uwe Ligges wrote:
> | > | On 03.08.2016 14:24, Dirk Eddelbuettel wrote:
> | > | > Then again, users of TravisCI know that just toggling
> | > | >
> | > | > _R_CHECK_FORCE_SUGGESTS_=FALSE
> | > |
> | > | I was travelling, hence a delayed response:
> | > |
> | > | Why users of TravisCI? It is documented in the manual. Setting it to
> | >
> | > Because Travis breaks your check as it works in a cleanroom with only the
> | > specified packages installed. As it (and that is the gist of my argument)
> | > should ...
> |
> | No, because if I suggest a package, I want to check also the code that
> | uses a suggested package. So I have to have the package installed.
>
> But then you are treating Suggests as Depends and installing irregardless.

No, it is different from Depends.

Depends implies something will be attached to the search list.  Suggests 
doesn't.  It is more like Imports, but without importing anything.

CRAN chooses to test in an environment where all Suggested packages are 
available.  They could do more testing (and I am pretty strongly in 
favour of that), e.g. *also* test in an environment where none of them 
are available.  But lots of packages will fail those tests, hence my 
request to you (not a gambit, I'm not playing a game) to estimate how 
many, and work out how to fix those packages.

Doing more testing will make it harder to get a package accepted on 
CRAN, but hopefully will mean that if it makes it there, it will be of 
better quality.

The other thing I am trying to do is to work out ways to spread out the 
work that CRAN does to other people.  I believe the current model will 
not last another year, and I'd rather that it didn't collapse 
completely.  This is unlikely to be my only request for help from people 
on this list.

>
> | > No, CRAN could just flip that toggle and run once.
> |
> | I do not get it: It won't make much of a difference because I have most
> | packages installed. It is only a diffrence for suggested packages that
>
> Which is a normal shortcut to make your life easier ... but not what other
> systems do. Travis CI runs start from scratch with an empty base. So does
> Debian for package build (and for subsequent tests such as the
> reproducibility tests). In each case only listed packages get installed.
>
> When we let R do its business Suggests is (currently) interpreted as
> Depends. I continue to claim that is not what it is for.
>
> As Thomas pointed out, Suggests: seems to be overloaded already to two
> distinct use cases.
>
> | are not available for my platform, and toggling it means checks always
> | fail then.
> |
> |
> | > What Duncan suggested was (as I understand it an empirically-driven
> | > assessment of what it would take to get from here (set to FALSE, tolerate bad
> | > Policy) to there (set to TRUE, IMHO better Policy adherence).
> |
> | You do not understand the environment variable, I believe.
>
> That is of course entirely possibly but it also seems that some of us in this
> discussion are continuously talking past each other. I tried to make my case
> but seemingly failed to explain it clearly enough.

That's the nature of the medium.  You need to be prepared to say the 
same thing in different ways so that dense people like me understand them.

Duncan Murdoch