try using $env:GITHUB_OUTPUT

Author: bgctw

.github/workflows/CI.yml

@@ -33,9 +33,9 @@ jobs:
       - run: Rscript -e 'install.packages("pak", repos = sprintf("https://r-lib.github.io/p/pak/stable/%s/%s/%s", .Platform$pkgType, R.Version()$os, R.Version()$arch))'
       - run: Rscript -e 'library(utils)'
       #- run: Rscript -e 'pak::pkg_install(c("any::ggplot2","any::RcppArmadillo","any::dtwclust"), upgrade = FALSE)' # TODO uncomment when solved R_HOME and utils package
-      - run: R_HOME=$(R RHOME)
       - run: |
-          echo "::set-output name=r_home::$R_HOME"
+          echo R_HOME=$(R RHOME) >> $env:GITHUB_OUTPUT
+      - run: |
           echo "$R_HOME"  
       - uses: cjdoris/julia-downgrade-compat-action@v1
         if: ${{ matrix.version == '1.10' }}
@@ -49,7 +49,8 @@ jobs:
       - uses: julia-actions/julia-buildpkg@v1
       - name: Run RCall
         run: |
-          julia -e "using RCall; println(RCall.R.version); println(ENV[\"R_HOME\"])"
+          julia -e "println(ENV[\"R_HOME\"])"
+          julia -e "import Pkg; Pkg.add("RCall"); using RCall; println(RCall.R.version)"
       - uses: julia-actions/julia-runtest@v1
         env:
           GROUP: ${{ matrix.group }}