tests/testthat/test-report.compare.loo.R

In report: Automated Reporting of Results and Statistical Models

skip_if_not_installed("brms")
skip_if_not_installed("loo")

test_that("report.compare.loo", {
  # Skip if dependencies not available
  skip_on_cran()

  set.seed(123)
  # Create simple brms models for testing
  suppressMessages(suppressWarnings({
    m1 <- brms::brm(
      mpg ~ qsec,
      data = mtcars,
      refresh = 0,
      iter = 300,
      seed = 123,
      chains = 1
    )
    m2 <- brms::brm(
      mpg ~ qsec + drat,
      data = mtcars,
      refresh = 0,
      iter = 300,
      seed = 123,
      chains = 1
    )
    m3 <- brms::brm(
      mpg ~ qsec + drat + wt,
      data = mtcars,
      refresh = 0,
      iter = 300,
      seed = 123,
      chains = 1
    )
  }))

  # Add LOO criterion
  suppressWarnings({
    m1 <- brms::add_criterion(m1, "loo")
    m2 <- brms::add_criterion(m2, "loo")
    m3 <- brms::add_criterion(m3, "loo")
  })

  # Compare models
  x <- suppressWarnings(brms::loo_compare(
    m1,
    m2,
    m3,
    model_names = c("m1", "m2", "m3")
  ))

  r <- report(x)
  expect_s3_class(r, c("report_text", "character"))
  expect_gt(nchar(r), 0)
  expect_true(grepl("best model", r, fixed = TRUE))
  expect_true(grepl("ELPD", r, fixed = TRUE))

  # Test with different options
  r2 <- report(x, include_IC = FALSE)
  expect_s3_class(r2, c("report_text", "character"))

  r3 <- report(x, include_ENP = TRUE)
  expect_s3_class(r3, c("report_text", "character"))
})