R/test_helpers.R

In golem: A Framework for Robust Shiny Applications

#' Test helpers
#'
#' These functions are designed to be used inside the tests
#' in your Shiny app package.
#'
#' @param object the object to test
#'
#' @return A testthat result.
#' @export
#' @rdname testhelpers
expect_shinytag <- function(object) {
  rlang::check_installed(
    "testthat",
    "to run the tests."
  )
  act <- testthat::quasi_label(rlang::enquo(object), arg = "object")
  act$class <- class(object)
  testthat::expect(
    "shiny.tag" %in% act$class,
    sprintf("%s has class %s, not class 'shiny.tag'.", act$lab, paste(act$class, collapse = ", "))
  )
  invisible(act$val)
}

#' @export
#' @rdname testhelpers
expect_shinytaglist <- function(object) {
  rlang::check_installed(
    "testthat",
    "to run the tests.",
    version = "3.0.0"
  )
  act <- testthat::quasi_label(rlang::enquo(object), arg = "object")
  act$class <- class(object)
  testthat::expect(
    "shiny.tag.list" %in% act$class,
    sprintf("%s has class '%s', not class 'shiny.tag.list'.", act$lab, paste(act$class, collapse = ", "))
  )
  invisible(act$val)
}

#' @export
#' @rdname testhelpers
#' @param ui output of an UI function
#' @param html deprecated
#' @param ... arguments passed  to `testthat::expect_snapshot()`
#' @importFrom attempt stop_if_not
expect_html_equal <- function(
  ui,
  html,
  ...
) {
  rlang::check_installed(
    "testthat",
    "to run the tests.",
    version = "3.0.0"
  )

  if (!missing(html)) {
    message(
      "`html` is no longer used inside `expect_html_equal()`"
    )
  }

  testthat::expect_snapshot(
    x = ui,
    ...
  )
}

#' @export
#' @rdname testhelpers
#' @param sleep number of seconds
#' @param R_path path to R. If NULL, the function will try to guess where R is.
expect_running <- function(
  sleep,
  R_path = NULL
) {
  rlang::check_installed(
    "testthat",
    "to run the tests.",
    version = "3.0.0"
  )
  testthat::skip_if_not_installed("pkgload")
  testthat::skip_if_not_installed("processx")
  testthat::skip_on_cran()

  # Ok for now we'll get back to this
  testthat::skip_if_not(interactive())

  # Oh boy using testthat and processx is a mess
  #
  # We want to launch the app in a background process,
  # but we don't have access to the same stuff depending on
  # where we call the tests
  #
  # + We can launch with pkgload::load_all(), but __only__ if the
  #   current wd is the same as the golem wd
  # + We can launch with library(lib = ) but __only__ if we are in the
  #   non interactive testthat environment, __where the current package
  #   has been installed in a temporary library__
  #
  # There are six ways to call tests:
  #
  # - (1) Running the test interactively (i.e cmd A + cmd Enter):
  #   + We're in interactive mode
  #   + We're not in testthat so no Sys.getenv("TESTTHAT_PKG")
  #   + The libPath is the default one
  #   + the wd is the golem path
  #   + We can use pkgload::load_all()
  #
  # - (2) Running the test inside the console, with devtools::test()
  #   + We're in interactive mode
  #   + We're in testthat so there is a Sys.getenv("TESTTHAT_PKG" )
  #   + The libPath is the default one
  #   + the wd is the golem path
  #   + We can use pkgload::load_all()
  #
  # - (3) Running the test inside the console, with devtools::check()
  #   + We're not interactive mode
  #   + We're in testthat so there is a Sys.getenv("TESTTHAT_PKG" )
  #   + the wd is a temp dir
  #   + The libPath is a temp one
  #   + We can't use pkgload
  #   + We can library()
  #
  # - (4) Clicking on the "Run Tests" button on test file File
  #   + We're not in interactive mode
  #   + We're not in testthat so there is a Sys.getenv("TESTTHAT_PKG" )
  #   + the wd is the golem path
  #   + We can use pkgload
  #
  # - (5) Clicking on the "Test" button in RStudio Build Pane
  #   + We're not in interactive mode
  #   + We're not in testthat so no Sys.getenv("TESTTHAT_PKG" )
  #   + the wd is the golem path
  #   + We can use pkgload
  #   This one is actually the tricky one: we need to detect that we
  #   are in testthat but non interactively, and inside the golem wd.
  #
  # - (6) Clicking on the "Check" button in RStudio Build Pane
  #   + We're not interactive mode
  #   + We're in testthat so there is a Sys.getenv("TESTTHAT_PKG" )
  #   + the wd is a temp dir
  #   + The libPath is a temp one
  #   + We can't use pkgload
  #   + We can library()
  #
  #   So two sum up, two times where we can do library(): is when
  #   we're not in an child process launched

  if (Sys.getenv("CALLR_CHILD_R_LIBS_USER") == "") {
    pkg_name <- pkgload::pkg_name()
    # We are not in RCMDCHECK
    go_for_pkgload <- TRUE
  } else {
    pkg_name <- Sys.getenv("TESTTHAT_PKG")
    go_for_pkgload <- FALSE
  }

  if (is.null(R_path)) {
    if (tolower(.Platform$OS.type) == "windows") {
      r_ <- normalizePath(file.path(Sys.getenv("R_HOME"), "bin", "R.exe"))
    } else {
      r_ <- normalizePath(file.path(Sys.getenv("R_HOME"), "bin", "R"))
    }
  } else {
    r_ <- R_path
  }

  if (go_for_pkgload) {
    # Using pkgload because we can
    shinyproc <- processx::process$new(
      command = r_,
      c(
        "-e",
        "pkgload::load_all(here::here());run_app()"
      )
    )
  } else {
    # Using the temps libPaths because we can
    shinyproc <- processx::process$new(
      echo_cmd = TRUE,
      command = r_,
      c(
        "-e",
        sprintf("library(%s, lib = '%s');run_app()", pkg_name, .libPaths())
      ),
      stdout = "|",
      stderr = "|"
    )
  }

  Sys.sleep(sleep)
  testthat::expect_true(shinyproc$is_alive())
  shinyproc$kill()
}