This action sets up an R environment for use in actions by:

• Downloading and caching a version of R by version and adding to PATH
• Registering problem matchers for error output
• Setting the following environment variables
  • NOT_CRAN=true
  • TZ=UTC
  • R_LIBS_USER=tempdir/Library
  • _R_CHECK_SYSTEM_CLOCK_=FALSE
• Removing the -fopenmp flags from Makeconf on macOS, which are not supported with Apple’s default Command Line Tools compilers.
• Appending ‘on GitHub Actions’ to the default HTTP user agent. This is useful to distinguish GitHub Actions package requests from other sources.
• Supplying the installed R version as a installed-r-version output.

• r-version ('release') - Version range or exact version of an R version to use.
• rtools-version ('') - Exact version of Rtools to use. Default uses latest suitable rtools for the given version of R.
• Ncpus ('1') - Value to set the R option Ncpus to.
• crayon.enabled ('NULL') - Value to set the R option crayon.enabled to.
• remove-openmp-macos (true) - If true, remove -fopenmp from the default compilation flags, e.g. SHLIB_OPENMP_CFLAGS, as the macOS Command Line Tools do not support OpenMP.
• http-user-agent ('default') - If "default" or "", sets the HTTPUserAgent option to e.g. for R 3.6.3 running on macOS Catalina, "R/3.6.3 R (3.6.3 x86_64-apple-darwin17.0 x86_64 darwin17.0) on GitHub Actions". If "release" sets the user agent to the default user agent for the current R release. Otherwise uses whatever value is passed to http-user-agent.
• install-r (true) - If “true” download and install R during the setup. If “false” use the existing installation in the GitHub Action image.
• windows-path-include-mingw (true) - If “true” put the 64 bit mingw directory from Rtools on the PATH for Windows builds.
• update-rtools (false) - Update rtools40 compilers and libraries to the latest builds.
• use-public-rspm (false) - Use the public version of RStudio package manager available at https://packagemanager.rstudio.com/ to serve binaries for Linux and Windows.
• extra-repositories ('') - One or more extra CRAN-like repositories to include in the repos global option

• installed-r-version - The full R version installed by the action

Basic:

steps:
- uses: actions/checkout@master
- uses: r-lib/actions/setup-r@v1
  with:
    r-version: '3.5.3' # The R version to download (if necessary) and use.
- run: Rscript -e 'print("hello")'

Matrix Testing:

jobs:
  build:
    runs-on: ubuntu-18.04
    strategy:
      matrix:
        R: [ '3.5.3', '3.6.1' ]
    name: R ${{ matrix.R }} sample
    steps:
      - uses: actions/checkout@master
      - name: Setup R
        uses: r-lib/actions/setup-r@v1
        with:
          r-version: ${{ matrix.R }}
      - run: Rscript -e 'print("hello")'

The scripts and documentation in this project are released under the MIT License

Contributions are welcome!