Removing archived CRAN packages before a build

[jwokaty]

          > Is there some process you used to figure out what dependencies were archived?

@jwokaty FWIW here is a little function you can use to find those CRAN packages that are installed on a builder but have vanished from CRAN:

find_vanished_CRAN_pkgs <- function(CRAN_repos="https://cran.r-project.org") {
    inst_pkgs <- installed.packages()[ , "Package"]
    is_cran <- sapply(inst_pkgs, function(pkg) "CRAN" %in% packageDescription(pkg)$Repository)
    inst_cran_pkgs <- inst_pkgs[is_cran]
    all_cran_pkgs <- available.packages(repos=CRAN_repos)[ , "Package"]
    setdiff(inst_cran_pkgs, all_cran_pkgs)
}

Returns the following on nebbiolo1:

> find_vanished_CRAN_pkgs()
 [1] "assertive.code"       "assertive.data"       "assertive.data.uk"   
 [4] "assertive.data.us"    "assertive.datetimes"  "assertive.properties"
 [7] "assertive.strings"    "assertive.types"      "multipanelfigure"    
[10] "optimr"               "rbokeh"               "Rcgmin"              
[13] "Rvmmin"              

We should probably think about having BBS automatically remove vanished packages (+ their rev deps) at the beginning of a run.

Originally posted by @hpages in #359 (comment)

Maybe there should also be some kind of notification that a CRAN package was removed so that we can evaluate the apt and pip dependencies.