WISH: Control 'repos' order in installation instructions

[HenrikBengtsson]

I'm prototyping CRANhaven, which serves as a fallback/backup repository for CRAN. The auto-generates installation instructions for such packages is:

install.packages('somepkg', repos = c('https://cranhaven.r-universe.dev', 'https://cloud.r-project.org'))

However, by design, I want the instructions to use CRANhaven as a last resort, not be the first one. So, something like:

install.packages('somepkg', repos = c('https://cloud.r-project.org', 'https://cranhaven.r-universe.dev'))

It would be handy if we could configure/control these installation instructions.

[dmurdoch]

I agree. For most of my packages, the main branch (chosen by default on R-universe) is not a release version, it's a development version. I've been told I can configure R-universe to choose a release instead, but I like having the easy availability of the devel version, it's just that I don't like the instructions that don't mention that's what you're getting.

So I'd like to customize the installation instructions. Instead of showing

# Install rgl in R:
install.packages('rgl', repos = c('https://dmurdoch.r-universe.dev', 'https://cloud.r-project.org'))

I'd choose

# Install the development version of rgl in R:
install.packages('rgl', repos = 'https://dmurdoch.r-universe.dev')

# Install the latest release of rgl:
install.packages('rgl', repos = 'https://cloud.r-project.org')

[jeroen]

@HenrikBengtsson have you tested your suggestion to work? Afaik, the ordering of repos does not matter much as R will always install the highest version it can find.

[HenrikBengtsson]

You're right. I saw a comment about this on R-help/R-devel some weeks ago, but forgot about this feature request.

Closing, since there's nothing you can do here.

[mojaveazure]

Afaik, the ordering of repos does not matter much as R will always install the highest version it can find

There is one exception to this rule: one can pass a filters argument to install.packages()/available.packages() that controls how R picks which packages to install. One available filter is "CRAN" that tells R to install the highest version of a package from a CRAN repository (named "CRAN" in getOption("repos")), even if a higher version exists on an alternate repository

For example, with digest, the current CRAN version is 0.6.35 while the current version on Dirk's R-universe is 0.6.35.2; as a test (using rocker/r-ver:latest)

> getOption('repos')
                                         CRAN
"https://p3m.dev/cran/__linux__/jammy/latest"
> (cran <- available.packages()['digest', 'Version']) # CRAN version of digest
[1] "0.6.35"
> (universe <- available.packages(repos = 'https://eddelbuettel.r-universe.dev/')['digest', 'Version']) # R-universe version of digest
[1] "0.6.35.2"
> cran < universe # check that R-universe has a higher version of digest than CRAN
[1] TRUE
> # basic install.packages(); highest version wins
> install.packages('digest', repos = c('https://eddelbuettel.r-universe.dev/', getOption('repos')), quiet = TRUE)
> packageVersion("digest")
[1] ‘0.6.35.2’
> packageVersion("digest") == universe
[1] TRUE
> # set the filter to use CRAN repos over alternate repos
> options(available_packages_filters = c('R_version', 'OS_type', 'subarch', 'CRAN', 'duplicates'))
> install.packages('digest', repos = c('https://eddelbuettel.r-universe.dev/', getOption('repos')), quiet = TRUE)
> packageVersion("digest")
[1] ‘0.6.35’
> packageVersion("digest") == universe # we have the CRAN version, despite R-universe being passed an higher
[1] FALSE
> # if passing a repos vector without a named CRAN repo (R-universe's default), the CRAN filter does nothing
> install.packages('digest', repos = c('https://eddelbuettel.r-universe.dev/', 'https://cloud.r-project.org'), quiet = TRUE)
> packageVersion("digest")
[1] ‘0.6.35.2’
> packageVersion("digest") == universe
[1] TRUE

It's not the simplest solution as it requires

• users to have a default CRAN repository set
• users to alter the default package filters
• R-universe to recommend using getOption("repos") over "https://cloud.r-project.org"

But having R-universe as a "last resort" should work with the "CRAN" filter and a named CRAN repository