[benjaminguttmann-avtq]

Problem

fs >= 2.0.0 (pulled in by shiny via sass/bslib) needs libuv headers, which the cflinuxfs stacks do not ship. The fs install failed, and because R exits 0 when install.packages fails for a dependency, the build still succeeded. As a result shiny and its dependencies were missing from the r 4.6.2 artifacts.

Changes

• internal/recipe/r.go
  • Run all R package installs (remotes, explicit deps, sub-deps) with USE_BUNDLED_LIBUV=1 via RunWithEnv, so fs builds its vendored libuv.
  • Add a verification step after the sub-dependency installs and before remove.packages("remotes"). It fails the build unless fs, the explicit deps (cli, curl, lifecycle, R6, rlang, withr, processx, callr, stringr) and the sub-deps (Rserve, forecast, shiny, plumber) can be loaded with requireNamespace. This catches both missing packages and broken native builds.
  • Introduce rExplicitDeps so the install and verification steps share one package list.
• Tests (recipe_compiled_test.go, new export_test.go)
  • Every package install sets USE_BUNDLED_LIBUV=1.
  • Verification runs before remotes is removed and covers fs, the explicit deps and the sub-deps.
  • The build fails with verifying installed R packages when verification fails.

Testing

• go test -race ./internal/recipe/ -run 'TestRRecipe|TestRserve' passes.
• Not run: the R verification snippet against a real R install, and a Docker/parity build of the r artifact. Please confirm via CI or make parity-test DEP=r.
• TestLibunwindRecipeBuild fails locally on macOS (trailing slash in TMPDIR). It fails the same way on main and is unrelated to this change.

Notes for reviewers

• Verification uses requireNamespace, which loads each package. It is slightly slower than installed.packages() but checks the failure this PR targets.
• The verify call uses plain Run, because it needs no extra environment.

Should fix the failing tests in cloudfoundry/r-buildpack#400

[Copilot]

🔵 Needs a closer look

FakeRunner-only coverage leaves bundled-libuv compilation, namespace loading, and exit-status propagation unverified in a real R/parity build on the target stacks.

No open issues 🎉

What changed in this PR

This PR updates the R recipe to use bundled libuv during package installation and fail the build when required packages cannot load, preventing incomplete R artifacts.

Changes:

• Sets USE_BUNDLED_LIBUV=1 for all R package installs.
• Shares the explicit dependency list between installation and verification, which runs before removing remotes.
• Adds tests for the install environment, verification ordering and package coverage, and verification failure handling.

File	Description
internal/​recipe/​recipe_compiled_test.go	Tests bundled-libuv settings and package verification behavior.
internal/​recipe/​r.go	Enables bundled libuv and verifies required packages before packaging.
internal/​recipe/​export_test.go	Exposes the verification command to external-package tests.

_{Review effort: Balanced}