[setup-r-dependencies]: set R_LIBS_USER if unset (#896)

gaborcsardi · web-flow · commit 9677f2e32657 · 2024-08-02T10:39:05.000+02:00
* [setup-r-dependencies]: set R_LIBS_USER if unset

* Cannot use env.R_LIBS_USER directly in R

Because it uses backslashes on Windows, which means
invalid escapes in R.

* Message about R_LIBS_USER

* Add NEWS for R_LIBS_USER setting

[ci skip]
diff --git a/NEWS.md b/NEWS.md
@@ -14,6 +14,10 @@
   unchanged, on all R versions. To avoid using a P3M snapshot on R 3.6.x,
   set the `RSPM_PIN_3_6` environment variable to `false`.
 
+* `[setup-r-dependencies]` now always sets the `R_LIBS_USER` GitHub
+  environment variable, so it can be used without `[setup-r]` or without
+  setting it manually (#881).
+
 * The example workflows now use their file names as workflow names.
   This is to make it easier to match worflow runs to workflow files.
   Most of the the `check-*` workflows use `R-CMD-check.yaml`, however,
diff --git a/setup-r-dependencies/action.yaml b/setup-r-dependencies/action.yaml
@@ -74,6 +74,12 @@ runs:
             message("R_LIBS_SITE is already set to ", lib)
             cat(sprintf("R_LIB_FOR_PAK=%s\n", strsplit(lib, .Platform$path.sep)[[1]][[1]]), file = Sys.getenv("GITHUB_ENV"), append = TRUE)
           }
+          if (nchar("${{ env.R_LIBS_USER && 'ok' || '' }}") == 0) {
+            message("R_LIBS_USER GH env var is unset, setting now: ", Sys.getenv("R_LIBS_USER"))
+            cat(sprintf("R_LIBS_USER=%s\n", Sys.getenv("R_LIBS_USER")), file = Sys.getenv("GITHUB_ENV"), append = TRUE)
+          } else {
+            message("R_LIBS_USER GH env var is already set: ", Sys.getenv("R_LIBS_USER"))
+          }
           cat("::endgroup::\n")
         shell: Rscript {0}
 
