expect_no_output <- function(...) {
  testthat::expect_output(..., regexp = NA)
}

expect_safe_and_unsafe_unwinding <- function(state,
                                             with_unsafe,
                                             with_safe) {
  early_exit <- function(expr) {
    tryCatch(expr, my_cnd = identity)
  }

  with_unsafe(list("var" = "foo"), NULL)
  expect_null(state[["var"]])

  with_safe(list("var" = "foo"), NULL)
  expect_null(state[["var"]])

  early_exit(with_safe(list("var" = "foo"), NULL))
  expect_null(state[["var"]])

  # Problematic behaviour with unsafe variant
  early_exit(with_unsafe(list("var" = "foo"), NULL))
  expect_equal(state[["var"]], "foo")
}

en_locale_or_skip <- function() {
  tryCatch(
    error = function(...) skip("Can't set locale"),
    warning = function(...) skip("Can't set locale"),
    with_collate("en_US.UTF-8", NULL)
  )
  "en_US.UTF-8"
}

skip_if_cannot_knit <- function() {
  skip_if_not_installed("knitr")
  skip_if_not_installed("rmarkdown")
  skip_if(!rmarkdown::pandoc_available())
}

# Used to skip tests that will fail when locale is set to C, for
# instance `with_language()` tests. These tests should only be run
# when using a locale like `en_US`.
skip_if_c_locale <- function() {
  lc_all <- Sys.getenv("LC_ALL", "")
  skip_if(lc_all %in% c("C", "C.UTF-8"))

  if (lc_all == "") {
    lang <- Sys.getenv("LANG", "")
    skip_if(lang %in% c("C", "C.UTF-8"))
  }
}