R/testUtils.R

In jefferys/JefferysRUtils: My bag of tricks for R coding

# Testing utilities for use with testthat

#' Extended equality tests
#'
#' This general test fixture extends \code{expect_equal} to support \code{NULL}.
#'
#' @param got The object to test.
#' @param want The expected value, may be \code{NULL}.
#' @param label Object label.
#' @param info Extra info.
#' @param ... Extra parameters passed to \code{\link{all.equal}}.
#' @return Called only for its side effects during testing.
#' @examples
#' \dontrun{
#' ### Pass
#' expect_equalOrNull( 1, 1 )
#' expect_equalOrNull( list( a= 1,b= 2 ), list( b= 2, a= 1 ))
#' x <- list( a= 1, b= 2)["c"]
#' expect_equalOrNull( x, NULL )
#'
#' ### Fail
#' expect_equalOrNull( 1, "1" )
#' expect_equalOrNull( 1, NULL )
#' expect_equalOrNull( NULL, 1 )
#' }
#' @export

expect_equalOrNull <- function( got, want, label= NULL, info= NULL, ... ) {
	if ( is.null( want )) {
		testthat::expect_null( got, label= label, info= info )
	}
	else {
		testthat::expect_equal( got, want, label= label, info= info, ...)
	}
}