test_that("ggsurvplot_facet creates the correct quanitty of subplots", {
  fit <- survfit(Surv(time, status) ~ sex, data=kidney)
  p <- ggsurvplot_facet(fit, kidney, facet.by='disease')
  .build <- ggplot_build(p)
  expect_equal(nrow(.build$data[[2]]),
               length(unique(kidney[['disease']])))

  fit <- survfit(Surv(time, status) ~ disease, data=kidney)
  p <- ggsurvplot_facet(fit, kidney, facet.by='sex')
  .build <- ggplot_build(p)
  expect_equal(nrow(.build$data[[2]]),
               length(unique(kidney[['sex']])))
})

test_that("ggsurvplot_facet calculates pvalue for each facet", {
  fit <- survfit(Surv(time, status) ~ sex, data=kidney)
  p <- ggsurvplot_facet(fit, kidney, facet.by='disease', pval = TRUE)
  .build <- ggplot_build(p)
  
  # Handle ggplot2 dev version layer access syntax change
  if (is_pkg_version_sup("ggplot2", "3.5.2")) {
    observed <- nrow(.build$plot@layers[[4]][['data']])
  } else {
    observed <- nrow(.build$plot$layers[[4]][['data']])
  }
  expect_equal(observed, length(unique(kidney[['disease']])))
})