Fix CI by skipping visual tests when vdiffr is not available (#4192)

* Skip visual tests when vdiffr is not available

* Add tweak to skip ggsave tests

* Update CMD-ckeck.yml

* Add http-user-agent

* Fix a comment

* Require vdiffr except when it's explicitly disabled

.github/workflows/R-CMD-check.yaml

@@ -24,17 +24,17 @@ jobs:
  config:
  - {os: windows-latest, r: '4.0', vdiffr: true, xref: true}
  - {os: macOS-latest, r: '4.0', vdiffr: true, xref: true}
- - {os: ubuntu-16.04, r: 'devel', vdiffr: false, xref: true, cran: "https://demo.rstudiopm.com/all/__linux__/xenial/latest"}
- - {os: ubuntu-16.04, r: '4.0', vdiffr: true, xref: true, cran: "https://demo.rstudiopm.com/all/__linux__/xenial/latest"}
- - {os: ubuntu-16.04, r: '3.6', vdiffr: false, xref: true, cran: "https://demo.rstudiopm.com/all/__linux__/xenial/latest"}
- - {os: ubuntu-16.04, r: '3.5', vdiffr: false, xref: true, cran: "https://demo.rstudiopm.com/all/__linux__/xenial/latest"}
- - {os: ubuntu-16.04, r: '3.4', vdiffr: false, xref: true, cran: "https://demo.rstudiopm.com/all/__linux__/xenial/latest"}
- - {os: ubuntu-16.04, r: '3.3', vdiffr: false, xref: true, cran: "https://demo.rstudiopm.com/all/__linux__/xenial/latest"}
- - {os: ubuntu-16.04, r: '3.2', vdiffr: false, xref: false, cran: "https://demo.rstudiopm.com/all/__linux__/xenial/latest"}
+ - {os: ubuntu-16.04, r: 'devel', vdiffr: false, xref: true,  rspm: "https://packagemanager.rstudio.com/cran/__linux__/xenial/latest", http-user-agent: "R/4.0.0 (ubuntu-16.04) R (4.0.0 x86_64-pc-linux-gnu x86_64 linux-gnu) on GitHub Actions"}
+ - {os: ubuntu-16.04, r: '4.0', vdiffr: true, xref: true,  rspm: "https://packagemanager.rstudio.com/cran/__linux__/xenial/latest"}
+ - {os: ubuntu-16.04, r: '3.6', vdiffr: false, xref: true,  rspm: "https://packagemanager.rstudio.com/cran/__linux__/xenial/latest"}
+ - {os: ubuntu-16.04, r: '3.5', vdiffr: false, xref: true,  rspm: "https://packagemanager.rstudio.com/cran/__linux__/xenial/latest"}
+ - {os: ubuntu-16.04, r: '3.4', vdiffr: false, xref: true,  rspm: "https://packagemanager.rstudio.com/cran/__linux__/xenial/latest"}
+ - {os: ubuntu-16.04, r: '3.3', vdiffr: false, xref: true,  rspm: "https://packagemanager.rstudio.com/cran/__linux__/xenial/latest"}
+ - {os: ubuntu-16.04, r: '3.2', vdiffr: false, xref: false,  rspm: "https://packagemanager.rstudio.com/cran/__linux__/xenial/latest"}
 
  env:
  R_REMOTES_NO_ERRORS_FROM_WARNINGS: true
- CRAN: ${{ matrix.config.cran }}
+ RSPM: ${{ matrix.config.rspm }}
  # don't treat missing suggested packages as error
  _R_CHECK_FORCE_SUGGESTS_: false
  # Some packages might unavailable on the older versions, so let's ignore xref warnings
@@ -49,6 +49,7 @@ jobs:
  - uses: r-lib/actions/setup-r@master
  with:
  r-version: ${{ matrix.config.r }}
+ http-user-agent: ${{ matrix.config.http-user-agent }}
 
  - uses: r-lib/actions/setup-pandoc@master
 
@@ -68,12 +69,11 @@ jobs:
 
  - name: Install system dependencies on Linux
  if: runner.os == 'Linux'
- env:
- RHUB_PLATFORM: linux-x86_64-ubuntu-gcc
  run: |
- Rscript -e "remotes::install_github('r-hub/sysreqs')"
- sysreqs=$(Rscript -e "cat(sysreqs::sysreq_commands('DESCRIPTION'))")
- sudo -s eval "$sysreqs"
+ while read -r cmd
+ do
+ eval sudo $cmd
+ done < <(Rscript -e 'writeLines(remotes::system_requirements("ubuntu", "16.04"))')
 
  - name: Install system dependencies on macOS
  if: runner.os == 'macOS'

tests/testthat/helper-vdiffr.R

@@ -2,4 +2,14 @@
 # - VDIFFR_RUN_TESTS is "false" (on Travis CI with older versions and dev version of R)
 # - CI is not set (on CRAN)
 
-expect_doppelganger <- vdiffr::expect_doppelganger
+if (requireNamespace("vdiffr", quietly = TRUE)) {
+ expect_doppelganger <- vdiffr::expect_doppelganger
+} else {
+ # If vdiffr is not available and visual tests are not explicitly disabled, raise error.
+ if (!identical(Sys.getenv("VDIFFR_RUN_TESTS"), "false")) {
+ abort("vdiffr is not installed")
+ }
+
+ # Otherwise, assign a dummy function
+ expect_doppelganger <- function(...) skip("vdiffr is not installed.")
+}

tests/testthat/test-ggsave.R

@@ -29,6 +29,10 @@ test_that("ggsave restores previous graphics device", {
 })
 
 test_that("ggsave uses theme background as image background", {
+ # FIXME: This should check svglite, but, at the time of writing this, there's already a binary
+ # package of svglite, and it can be installed even if the dependency is not available, surprisingly...
+ skip_if_not_installed("systemfonts")
+
  path <- tempfile()
  on.exit(unlink(path))
  p <- ggplot(mtcars, aes(disp, mpg)) +