Add skip_unless_r() (#2094)

Fixes #2022

Author: MichaelChirico

NAMESPACE

@@ -189,6 +189,7 @@ export(skip_on_covr)
 export(skip_on_cran)
 export(skip_on_os)
 export(skip_on_travis)
+export(skip_unless_r)
 export(snapshot_accept)
 export(snapshot_review)
 export(source_dir)

NEWS.md

@@ -4,6 +4,7 @@
 * `expect_s4_class()` now supports unquoting (@stibu81, #2064).
 * `it()` now finds the correct evaluation environment in more cases (@averissimo, #2085).
 * Fixed an issue preventing compilation from succeeding due to deprecation / removal of `std::uncaught_exception()` (@kevinushey, #2047).
+* New `skip_unless_r()` to skip running tests on unsuitable versions of R, e.g. `skip_unless_r(">= 4.1.0")` to skip tests that require, say, `...names` (@MichaelChirico, #2022)
 
 # testthat 3.2.3
 

R/expect-self-test.R

@@ -94,6 +94,9 @@ expect_no_failure <- function(expr) {
 expect_snapshot_skip <- function(x, cran = FALSE) {
   expect_snapshot_error(x, class = "skip", cran = cran)
 }
+expect_skip <- function(code) {
+  expect_condition(code, class = "skip")
+}
 expect_no_skip <- function(code) {
   expect_no_condition(code, class = "skip")
 }

R/skip.R

@@ -126,6 +126,30 @@ package_version <- function(x) {
   utils::packageVersion(x)
 }
 
+#' @export
+#' @param spec A version specification like '>= 4.1.0' denoting that this test
+#'   should only be run on R versions 4.1.0 and later.
+#' @rdname skip
+skip_unless_r <- function(spec) {
+  parts <- unlist(strsplit(spec, " ", fixed = TRUE))
+  if (length(parts) != 2L) {
+    cli::cli_abort("{.arg spec} should be a comparison like '>=' and an R version separated by a space.")
+  }
+  comparator <- match.fun(parts[1L])
+  required_version <- numeric_version(parts[2L])
+
+  current_version <- getRversion()
+  skip_if_not(
+    comparator(current_version, required_version),
+    sprintf(
+      "Current R version (%s) does not satisfy requirement (%s %s)",
+      current_version, parts[1L], required_version
+    )
+  )
+}
+# for mocking
+getRversion <- NULL
+
 #' @export
 #' @rdname skip
 skip_if_offline <- function(host = "captive.apple.com") {

man/skip.Rd

@@ -88,3 +88,11 @@
 
     Reason: On Windows i386
 
+# skip_unless_r gives the expected output
+
+    Reason: Current R version (4.5.0) does not satisfy requirement (>= 999.999.999)
+
+---
+
+    Reason: Current R version (4.5.0) does not satisfy requirement (== 0.0.0)
+

tests/testthat/_snaps/skip.md

@@ -135,3 +135,22 @@ test_that("can refine os with arch", {
   expect_no_skip(skip_on_os("windows", "x86_64"))
   expect_no_skip(skip_on_os("linux", "i386"))
 })
+
+test_that("skip_unless_r works as expected", {
+  expect_no_skip(skip_unless_r(">= 0.0.0"))
+  expect_no_skip(skip_unless_r(paste("==", getRversion())))
+  expect_no_skip(skip_unless_r("<= 999.999.999"))
+
+  expect_skip(skip_unless_r(">= 999.999.999"))
+  expect_skip(skip_unless_r("== 0.0.0"))
+  expect_skip(skip_unless_r("<= 0.0.0"))
+
+  expect_error(skip_unless_r("idfjdij"), "should be a comparison like '>='", fixed = TRUE)
+})
+
+test_that("skip_unless_r gives the expected output", {
+  local_mocked_bindings(getRversion = \() numeric_version("4.5.0"))
+
+  expect_snapshot_skip(skip_unless_r(">= 999.999.999"))
+  expect_snapshot_skip(skip_unless_r("== 0.0.0"))
+})