Add test coverage for non-finite PIT warning

Author: utkarshpawade

tests/testthat/test-ppc-loo.R

@@ -59,6 +59,19 @@ test_that("ppc_loo_pit_overlay works with boundary_correction=FALSE", {
   expect_gg(p1)
 })
 
+test_that(".kde_correction warns when PIT values are non-finite", {
+  set.seed(123)
+  pit_vals <- c(stats::runif(500), Inf)
+  expect_warning(
+    out <- .kde_correction(pit_vals, bw = "nrd0", grid_len = 128),
+    "Non-finite PIT values are invalid"
+  )
+  expect_type(out, "list")
+  expect_true(all(c("xs", "bc_pvals") %in% names(out)))
+  expect_equal(length(out$xs), 128)
+  expect_equal(length(out$bc_pvals), 128)
+})
+
 test_that("ppc_loo_pit_qq returns ggplot object", {
   skip_if_not_installed("rstanarm")
   skip_if_not_installed("loo")