tests/testthat/test-mdt_moderated.R

In cedricbatailler/JSmediation: Mediation Analysis Using Joint Significance

test_that("used models are correctly specified", {
  data <-
    ho_et_al %>%
    dplyr::mutate(condition_c =
                    build_contrast(condition,
                                   "High discrimination",
                                   "Low discrimination"))

  js_model <-
    data %>%
    mdt_moderated(condition_c, hypodescent, linkedfate, sdo)

  models <-
    list(formula(hypodescent ~ condition_c * sdo),
         formula(linkedfate ~ condition_c * sdo),
         formula(hypodescent ~ (condition_c + linkedfate) * sdo)) %>%
    purrr::map(~lm(.x, data))

  models_js <- purrr::pluck(js_model, "js_models")

  expect_equal(models_js, models, ignore_attr = TRUE)
})

test_that("mdt_moderated does not throw error", {
  dataset <-
    ho_et_al %>%
    dplyr::mutate(condition_c =
                    build_contrast(condition,
                                   "High discrimination",
                                   "Low discrimination"),
                  linkedfate_c =
                    scale(linkedfate, scale = FALSE),
                  sdo_c =
                    scale(sdo, scale = FALSE))

  expect_silent(
    mdt_moderated(dataset,
                  condition_c,
                  hypodescent,
                  linkedfate_c,
                  sdo_c)
  )
})

test_that("print method for mdt_moderated does not throw error", {
  dataset <-
    ho_et_al %>%
    dplyr::mutate(condition_c =
                    build_contrast(condition,
                                   "High discrimination",
                                   "Low discrimination"),
                  linkedfate_c =
                    scale(linkedfate, scale = FALSE),
                  sdo_c =
                    scale(sdo, scale = FALSE))

  model <-
    mdt_moderated(dataset,
                  condition_c,
                  hypodescent,
                  linkedfate_c,
                  sdo_c)

  expect_output(print(model))

})

test_that("print method for mdt_moderated throws message when a variable is not contrast-coded/centered", {
  dataset <-
    ho_et_al %>%
    dplyr::mutate(condition_c =
                    build_contrast(condition,
                                   "High discrimination",
                                   "Low discrimination"),
                  linkedfate_c =
                    scale(linkedfate, scale = FALSE))

  model <-
    mdt_moderated(dataset,
                  condition_c,
                  hypodescent,
                  linkedfate_c,
                  sdo)

  expect_message(print(model))
})

test_that("add_index method for mdt_moderated does not throw error when used as intented", {
  dataset <-
    ho_et_al %>%
    dplyr::mutate(condition_c =
                    build_contrast(condition,
                                   "High discrimination",
                                   "Low discrimination"),
                  linkedfate_c =
                    scale(linkedfate, scale = FALSE),
                  sdo_c =
                    scale(sdo, scale = FALSE))

  model <-
    mdt_moderated(dataset,
                  condition_c,
                  hypodescent,
                  linkedfate_c,
                  sdo_c)

  expect_error(add_index(model))
  expect_silent(add_index(model, stage = 1))
  expect_silent(add_index(model, stage = 2))
  expect_silent(add_index(model, stage = "total"))

})

test_that("Type checks work as intended in mdt_moderated", {
  data("ho_et_al")

  ho_et_al$condition_c <- build_contrast(ho_et_al$condition,
                                         "Low discrimination",
                                         "High discrimination")
  ho_et_al$foo <- "foo"

  expect_error(mdt_moderated(ho_et_al, foo, hypodescent, linkedfate, sdo))
  expect_error(mdt_moderated(ho_et_al, condition_c, foo, linkedfate, sdo))
  expect_error(mdt_moderated(ho_et_al, condition_c, hypodescent, foo, sdo))
  expect_error(mdt_moderated(ho_et_al, condition_c, hypodescent, linkedfate, foo))

})