feat(helper-setup): Add the checkmate_err_msg helper

testthat/helper-setup.R

@@ -125,3 +125,30 @@ get_test_conns <- function() {
 
   return(test_conns)
 }
+
+
+#' Parse checkmate assertions for testthat compatibility
+#' @description
+#'   The error messages generated by `checkmate` are formatted to look nicely in the console by the
+#'   addition of `*` and `\n` characters.
+#'
+#'   This means that checking these errors with `testthat::expect_error()` will often fail or will be harder to read
+#'   in the test since we need to manually insert `*` and `\n` to the comparison pattern to match the error message.
+#'
+#'   This helper function intercepts the `checkmate` error message and removes the `*` and `\n` characters to allow for
+#'   human readable error checking.
+#' @return
+#'   The checkmate error without `*` and `\n` characters.
+#' @noRd
+checkmate_err_msg <- function(expr) {
+  tryCatch(
+    expr,
+    error = \(e) {
+      e$message |>
+        stringr::str_remove_all(stringr::fixed("\n *")) |>
+        stringr::str_remove_all(stringr::fixed("* ")) |>
+        simpleError(message = _) |>
+        stop()
+    }
+  )
+}