[CI][R] R 4.0 jobs are failing because purrr 1.1.0 requires R 4.1 or later

[kou]

Describe the bug, including details regarding any error messages, version, and platform.

r-binary-packages:
https://github.com/ursacomputing/crossbow/actions/runs/16247251313/job/45872086489#step:13:254

ERROR: dependency ‘purrr’ is not available for package ‘arrow’

test-r-versions:
https://github.com/ursacomputing/crossbow/actions/runs/16243632256/job/45863338459#step:5:775

 #21 90.25 Skipping 1 packages not available: purrr
 #21 90.25 Installing 9 packages: rlang, lifecycle, vctrs, bit, cpp11, tidyselect, purrr, bit64, assertthat
 #21 102.3 Error: (converted from warning) package ‘purrr’ is not available for this version of R
 #21 102.3 ‘purrr’ version 1.1.0 is in the repositories but depends on R (>= 4.1)
 #21 102.3 ‘purrr’ version 1.1.0 is in the repositories but depends on R (>= 4.1)

Can we drop support for R 4.0 after 21.0.0 release? Or should we keep R 4.0 support?

Component(s)

Continuous Integration, R

[kou]

https://purrr.tidyverse.org/news/index.html#purrr-110

purrr now requires R >= 4.1, so we can rely on the base pipe and lambda syntax (#1177).

[amoeba]

I think we can remove support for R 4.0 after the 21 monorepo release. We might even want an out of cycle R-only release.

The R package tries to follow the tidyverse R version support policy and, with R 4.5 being released in 2025-04-11, we can drop 4.0.

cc @thisisnic @nealrichardson @jonkeane

[thisisnic]

Sounds good to me!

[nealrichardson]

It's annoying that R's dependency resolver can't handle this, but sure, sounds like we can drop 4.0. If we need a quick fix to drop it from CI, that's fine, but sounds like from that release note that there are some updates we can do to the code (or at least examples and vignettes) as a result of dropping 4.0 support, so we should make an issue to do that.

[amoeba]

Good called @nealrichardson. Filed as #47106.

[jonkeane]

Yup, agreed with y'all.

[thisisnic]

Issue resolved by pull request 47285
#47285