Weird installation error if installing to a different lib that is not on the lib path

[gaborcsardi]

For this you need the dev version (or just a different version, really) of usethis in a regular library, and then install usethis and devtools to another library. E.g.

dir.create(lib1 <- tempfile())
pak::pkg_install("r-lib/usethis", ask = FALSE, lib = lib1)
.libPaths(c(lib1, .libPaths()))

library(usethis)
dir.create(lib2 <- tempfile())
install.packages(c("devtools", "usethis"), lib = lib2)

** testing if installed package can be loaded
Error: package or namespace load failed for 'devtools':
 .onAttach failed in attachNamespace() for 'devtools', details:
  call: value[[3L]](cond)
  error: Package 'usethis' version 1.4.0 cannot be unloaded:
 Error in unloadNamespace(package) : namespace 'usethis' is imported by 'devtools' so cannot be unloaded

Error: loading failed
Execution halted
ERROR: loading failed

Is there a reason why devtools can't simply just depend on usethis?

[jimhester]

Is there a reason why devtools can't simply just depend on usethis?

Yes, we wanted the use_*() functions to be depreciated in devtools, but still attach usethis to the search path, so only functions called with devtools:: would have a deprecation message. The problem with just using Depends is the devtools functions then come before the usethis functions in the search path, so you get deprecation messages when calling the unqualified function, e.g. use_readme_md().

We could now probably remove the deprecation messages for the next release and just use Depends.

[gaborcsardi]

I think a workaround is to check where the imported package is coming from, that's in the namespace info, see getNapespaceInfo(), and add a lib.loc arg to the library() call, to make sure the same package is attached.

[lock]

This old issue has been automatically locked. If you believe you have found a related problem, please file a new issue (with reprex) and link to this issue. https://reprex.tidyverse.org/