R/rename.R

In r-hyperspec/hySpc.dplyr: Fortify hyperSpec for Use with dplyr

#' rename for hyperSpec objects
#'
#' rename extra data columns of hyperSpec objects.
#' Special column `$spc` contains the spectra matrix.
#' Unlike dplyr::select() dplyr::rename() keeps all the variables of the data frame intact.
#' However, if `$spc` is renamed, the result is an error instead of a hyperSpec object.
#'
#'
#'
#'
#'
#' @inheritParams dplyr::rename
#' @include setLabels.R
#' @seealso [dplyr::rename()]
#' @return hyperSpec object. If `$spc` is renamed, the result is an error.
#' @include unittest.R
#' @importFrom dplyr rename
#' @importFrom hyperSpec assert_hyperSpec
#' @importFrom hyperSpec labels labels<-
#' @export
#'
#' @examples
#'
#' laser %>%
#'   rename(filename2 = filename) %>%
#'   head() # results in a hyperSpec object
rename.hyperSpec <- function(.data, ...) {

  # Check if user passed in a hyperSpec object
  assert_hyperSpec(.data)

  # Use dplyr::rename() to rename hyperSpec object data slot
  res <- rename(.data@data, ...)

  # Check if $spc was renamed
  if (!"spc" %in% colnames(res)) {

    # Throw an error
    stop("$spc cannot be renamed")
  } else {

    # Set labels
    setLabels_rename(.data, res)
  }
}

# Begin unit testing (UT)
hySpc.testthat::test(rename.hyperSpec) <- function() {
  context("rename.hyperSpec")

  test_that("non hyperSpec objects are rejected", {
    df <- data.frame(a = NA, b = NA)
    expect_error(rename.hyperSpec(df))
  })

  test_that("renaming $spc throws an error", {
    expect_error(rename.hyperSpec(chondro, spc_newname = spc))
  })

  test_that("labels attribute when returning hyperSpec object", {
    tmp <- rename.hyperSpec(chondro, region = clusters)
    tmp <- rename.hyperSpec(tmp, clusters = region)
    expect_equal(labels(tmp), labels(chondro))
  })
}