Change the default behavior to RENV_PATHS_PREFIX_AUTO=TRUE

[colearendt]

By default, renv creates caches that are used (in an incompatible fashion) across differing linux OSes

By setting RENV_PATHS_PREFIX_AUTO=TRUE, this can be remedied for different linux operating systems. We should do this by default so that starting projects on different operating systems "just works" on renv (modulo package rebuilding).

There may be ways to mitigate a one-time breakage with existing project options, one-time symlinks, etc.

[kevinushey]

This would be worth including in a 1.0.0 release, since it'd be a potentially breaking change.

[kevinushey]

Punted due to time constraints + danger in making such a breaking change here.

[HenrikBengtsson]

Maybe you could synchronize a change to RENV_PATHS_PREFIX_AUTO=TRUE with the upcoming R 4.4.0 release (April/May 2024)? That's when people have to reinstall their packages anyway. You could stay backward compatible by only setting this default for R (>= 4.4), e.g.

.onLoad <- function(libname, pkgname) {
  if (getRversion() >= "4.4") {
    env <- Sys.getenv("RENV_PATHS_PREFIX_AUTO", NA_character_)
    if (is.na(env)) Sys.setenv(RENV_PATHS_PREFIX_AUTO = "TRUE")
  }
  ...
}

I guess you could roll that out already now.

[kevinushey]

@HenrikBengtsson that is an excellent idea -- I'll do that!

[kevinushey]

This has been implemented. Thanks again for the suggestion @HenrikBengtsson!