R/expect_neet.R

In softloud/neet: Coding to code::proof

#' Test for non-empty thing of expected type
#'
#' @param thing_to_test An object to test, such as a numeric, character, list,
#' etc.
#' @param expected_class Expected output of `class(thing_to_test)`.
#'
#' A *neet test* tests for **non-empty** thing of **expected type**. This
#' is what is referred to as a *boundary condition* test in RStudio's primers
#' (todo: citation).
#'
#' These expectations are intended to integrate into minimal testing workflow
#' *for development* of data analyses. When developing a function, we will change parameters,
#' and structure of the pipeline. These tests
#' enable the developer to feel reassured the pipeline's functions are
#' outputting non-empty thing of expected type, while the developer decides on
#' the best structure for an analysis pipeline.
#'
#' A `character` string will be checked for being of string-length > 1.
#'
#' A `numeric` is checked for being non-empty.
#'
#' A `numint` is checked for being numeric or integer.
#'
#' An `integer` is checked for being of length > 1.
#'
#' A `list`` is checked for being of length > 1.
#'
#' A `data.frame` is checked for having at least one row.
#'
#' A `ggplot` object is checked for successfully running.
#'
#'
#' `assert_neet` tests the input is non-empty and of expected type, and
#' `expect_neet` is an expectation for [test_that] that checks the output is
#' non-empty and of expected type
#' `test_neet` is a test for [testthat]
#'
#' @family neet Test for non-empty thing of expected type.
#'
#' @export

expect_neet <- function(thing_to_test, expected_class) {
  # we expect non-empty
  expect_nonempty(thing_to_test)

  if (expected_class == "numint") {
    testthat::expect_true(is.numeric(thing_to_test) | is.integer(thing_to_test))
  } else if (expected_class == "ggplot") {
    testthat::expect_s3_class(thing_to_test, "ggplot")
  } else {
    # thing of expected type
    testthat::expect_true(expected_class %in% class(thing_to_test))

  }
}


#' Test for non-empty thing of expected type.
#'
#' @inheritParams expect_neet
#'
#' @family neet Test for non-empty thing of expected type.
#'
#' @export

test_neet <-
  function(thing_to_test,
           expected_class) {
    testthat::test_that("neet", {
      expect_neet(thing_to_test, expected_class)
    })
  }


#' Check input is non-empty and expected type
#'
#' @inheritParams expect_neet
#'
#' @family neet Test for non-empty thing of expected type.
#'
#' @export

assert_neet <- function(thing_to_test, expected_class) {
  # we expect non-empty
  assertthat::not_empty(thing_to_test)
  # thing of expected type
  #
  if (expected_class == "numint") {
    expected_class <- c("numeric", "integer")
  }

  assertthat::assert_that(
    sum(expected_class %in% class(thing_to_test))
    >= 1,
    msg = paste0("Input argument '",
      deparse(substitute(thing_to_test)),
                "' not of expected type: ",
                expected_class, ".")
  )
}