rstan.yaml

# Build rstan from source against this branch's RcppParallel.
#
# The 'downstream' job in R-CMD-check.yaml is a stand-in for this: it compiles a
# small translation unit using the two TBB APIs StanHeaders needs. That catches
# the breakage this workflow exists to rule out, in seconds rather than the best
# part of an hour -- so this is deliberately manual, for when the real thing is
# worth waiting for (before a release, or after touching the Windows TBB setup).
on:
  workflow_dispatch:
    inputs:
      r-version:
        description: "R version (4.2 uses Rtools42, which has no oneTBB)"
        required: true
        default: "4.2"
      os:
        description: "Runner to build on"
        required: true
        default: "windows-latest"
        type: choice
        options:
          - windows-latest
          - macOS-latest
          - ubuntu-latest
      fit-model:
        description: "Also compile and fit a tiny Stan model (slow)"
        required: false
        default: false
        type: boolean

name: rstan

jobs:
  rstan:
    runs-on: ${{ inputs.os }}

    name: rstan (${{ inputs.os }}, R ${{ inputs.r-version }})

    # building rstan from source is slow, and slower still on Windows
    timeout-minutes: 120

    env:
      GITHUB_PAT: ${{ secrets.GITHUB_TOKEN }}
      VERBOSE: 1
      # rstan's own guidance for building it from source
      MAKEFLAGS: -j2

    defaults:
      run:
        shell: bash

    steps:
      - uses: actions/checkout@v4

      - uses: r-lib/actions/setup-r@v2
        with:
          r-version: ${{ inputs.r-version }}
          use-public-rspm: true

      - name: install RcppParallel from this branch
        run: R CMD INSTALL --preclean .

      - name: report how RcppParallel resolved TBB
        run: Rscript .github/scripts/report-tbb-config.R

      # binaries are fine for everything except rstan and StanHeaders, which are
      # the packages that actually consume RcppParallel's flags. this is
      # rstan's Imports plus its LinkingTo, minus RcppParallel (installed above)
      # and StanHeaders (built from source below)
      # NOTE: a bare 'Rscript' has no repository configured -- setup-r arranges
      # that only for the steps it wraps -- so name one explicitly here and in
      # every install.packages() call below
      - name: install rstan's dependencies
        run: |
          Rscript -e 'options(repos = c(CRAN = Sys.getenv("RSPM", unset = "https://cloud.r-project.org"))); install.packages(c("Rcpp","RcppEigen","BH","inline","gridExtra","loo","pkgbuild","QuickJSR","ggplot2"))'

      # dependencies = FALSE so that resolving StanHeaders/rstan can't quietly
      # pull CRAN's RcppParallel over the one we just built -- that would turn
      # this into a test of the released package instead
      - name: install StanHeaders and rstan from source
        run: |
          Rscript -e 'options(repos = c(CRAN = Sys.getenv("RSPM", unset = "https://cloud.r-project.org"))); install.packages(c("StanHeaders","rstan"), type = "source", dependencies = FALSE, INSTALL_opts = "--no-multiarch")'

      # compare against this checkout's DESCRIPTION rather than looking for a
      # '.9000' suffix, so this keeps working across development version bumps
      - name: check RcppParallel is still the one we built
        run: |
          Rscript -e 'installed <- packageVersion("RcppParallel"); expected <- package_version(read.dcf("DESCRIPTION")[1L, "Version"]); writeLines(sprintf("RcppParallel %s (expected %s)", installed, expected)); if (installed != expected) stop("RcppParallel was replaced by a different build; the rstan build did not test this branch")'

      - name: load rstan
        run: |
          Rscript -e 'library(rstan); print(rstan::stan_version())'

      - name: compile and fit a tiny model
        if: ${{ inputs.fit-model }}
        run: Rscript .github/scripts/rstan-fit-check.R