R/assertions.R

In r-hub/crandeps: CRAN Package Dependencies

#' @importFrom assertthat assert_that on_failure<-

is_string <- function(x) {
  is.character(x) && length(x) == 1 && !is.na(x)
}

on_failure(is_string) <- function(call, env) {
  paste0(deparse(call$x), " is not a string (length 1 character)")
}

is_flag <- function(x) {
  is.logical(x) && length(x) == 1 && !is.na(x)
}

on_failure(is_flag) <- function(call, env) {
  paste0(deparse(call$x), " is not a flag (length 1 logical)")
}