R/s3-ordered.R

In constructive: Display Idiomatic Code to Construct Most R Objects

#' Constructive options for class 'ordered'
#'
#' These options will be used on objects of class 'ordered'.
#'
#' Depending on `constructor`, we construct the object as follows:
#' * `"ordered"` (default): Build the object using `ordered()`, levels won't
#'   be defined explicitly if they are in alphabetical order (locale dependent!)
#' * `"factor"` : Same as above but build the object using `factor()` and `ordered = TRUE`.
#' * `"new_ordered"` : Build the object using `vctrs::new_ordered()`. Levels are
#'   always defined explicitly.
#' * `"next"` : Use the constructor for the next supported class. Call `.class2()`
#'   on the object to see in which order the methods will be tried.
#' * `"integer"` : We define as an integer vector and repair attributes
#'
#' @param constructor String. Name of the function used to construct the object, see Details section.
#' @inheritParams opts_atomic
#'
#' @return An object of class <constructive_options/constructive_options_ordered>
#' @export
opts_ordered <- function(constructor = c("ordered", "factor", "new_ordered", "next", "integer"), ...) {
  .cstr_options("ordered", constructor = constructor[[1]], ...)
}

#' @export
#' @method .cstr_construct ordered
.cstr_construct.ordered <- function(x, ...) {
  opts <- list(...)$opts$ordered %||% opts_ordered()
  if (is_corrupted_ordered(x) || opts$constructor == "next") return(NextMethod())
  UseMethod(".cstr_construct.ordered", structure(NA_integer_, class = opts$constructor))
}

is_corrupted_ordered <- function(x) {
  # FIXME
  typeof(x) != "integer"
}

#' @export
#' @method .cstr_construct.ordered ordered
.cstr_construct.ordered.ordered <- function(x, ...) {
  levs <- levels(x)
  args <- list(setNames(as.character(x), names(x)))
  default_levs <- sort(unique(as.character(x)))
  if (!identical(default_levs, levs)) args$levels <- levs
  if (NA %in% levs) args["exclude"] <- list(NULL)
  if (length(args) == 1) {
    code <- .cstr_apply(args, "ordered", new_line =  FALSE, ...)
  } else {
    code <- .cstr_apply(args, "ordered", ...)
  }
  repair_attributes_ordered(x, code, ...)
}

#' @export
#' @method .cstr_construct.ordered factor
.cstr_construct.ordered.factor <- function(x, ...) {
  levs <- levels(x)
  args <- list(setNames(as.character(x), names(x)))
  default_levs <- sort(unique(as.character(x)))
  if (!identical(default_levs, levs)) args$levels <- levs
  if (NA %in% levs) args["exclude"] <- list(NULL)
  args$ordered <- TRUE
  code <- .cstr_apply(args, "factor", ...)
  repair_attributes_ordered(x, code, ...)
}

#' @export
#' @method .cstr_construct.ordered new_ordered
.cstr_construct.ordered.new_ordered <- function(x, ...) {
  levs <- levels(x)
  code <- .cstr_apply(list(setNames(as.integer(x), names(x)), levels = levs), "vctrs::new_ordered", ...)
  repair_attributes_ordered(x, code, ...)
}

#' @export
#' @method .cstr_construct.ordered integer
.cstr_construct.ordered.integer <- function(x, ...) {
  .cstr_construct.integer(x, ...)
}

repair_attributes_ordered <- function(x, code, ..., pipe = NULL) {
  .cstr_repair_attributes(
    x, code, ...,
    pipe = pipe,
    ignore = "levels",
    idiomatic_class = c("ordered", "factor")
  )
}