unname_chunks.R

#' @title Unname chunks in a single file
#'
#' @description Unname in a single file all chunks,
#' or alternatively only unname the chunknames with a given prefix.
#' In both cases, the chunk name "setup" is preserved, that chunk is never unnamed.
#'
#' @returns Always returns TRUE invisibly. Called for side effects.
#'
#' @inherit name_chunks details
#'
#' @template path
#' @template chunk_name_prefix
#'
#' @export
#'
#' @examples
#' # remove all chunklabels except the one named 'setup'
#' temp_file_path <- file.path(tempdir(), "test1.Rmd")
#' file.copy(system.file("examples", "example4.Rmd", package = "namer"),
#'           temp_file_path,
#'           overwrite = TRUE)
#' unname_chunks(temp_file_path)
#' if(interactive()){
#' file.edit(temp_file_path)
#' }
#' # remove all chunk labels starting with 'example4'
#' temp_file_path <- file.path(tempdir(), "test2.Rmd")
#' file.copy(system.file("examples", "example4.Rmd", package = "namer"),
#'           temp_file_path,
#'           overwrite = TRUE)
#' unname_chunks(temp_file_path,chunk_name_prefix='example4')
#' if(interactive()){
#' file.edit(temp_file_path)
#' }
unname_chunks <- function(path, chunk_name_prefix = NULL) {
  # read the whole file
  lines <- readLines(path)

  # get chunk info
  chunk_headers_info <- get_chunk_info(lines)

  # early exit if no chunk
  if (is.null(chunk_headers_info)) {
    return(invisible("TRUE"))
  }

  if (is.null(chunk_name_prefix)) {
    # preserve the setup label, delete the others
    chunk_headers_info$name[chunk_headers_info$name != "setup"] <- ""
  } else {
    # preserve labels not starting with chunk_name_prefix
    del_labels <- strtrim(chunk_headers_info$name, nchar(chunk_name_prefix)) %in%
      chunk_name_prefix
    setup_label <- !(chunk_headers_info$name %in% "setup")
    del_labels <- del_labels & setup_label
    chunk_headers_info$name[del_labels] <- ""
  }

  newlines <- re_write_headers(chunk_headers_info)

  lines[newlines$index] <- newlines$line

  # save file
  writeLines(lines, path)

  return(invisible(TRUE))
}

#' @title  Unname chunks of all Rmds in a dir
#'
#' @description  Name unnamed chunks in a dir using the filenames with extension stripped as basis.
#'
#' @returns Always returns TRUE invisibly. Called for side effects.
#'
#' @inherit name_chunks details
#'
#' @template dir
#'
#' @export
#'
#' @examples
#' temp_dir <- tempdir()
#' # just to make sure we're not overwriting
#' if(fs::dir_exists(file.path(temp_dir, "examples"))){
#' fs::dir_delete(file.path(temp_dir, "examples"))
#' }
#' fs::dir_copy(system.file("examples", package = "namer"),
#'             temp_dir)
#'  # this is an example file that'd fail
#' fs::file_delete(file.path(temp_dir,
#'                          "examples", "example4.Rmd"))
#' name_dir_chunks(temp_dir)
#' if(interactive()){
#' file.edit(file.path(temp_dir,
#'                    "examples", "example1.Rmd"))
#' }
unname_dir_chunks <- function(dir) {
  rmds <- fs::dir_ls(dir, regexp = "*.[Rr]md")
  purrr::walk(rmds, chatty_unname_chunks)
  return(invisible(TRUE))
}

chatty_unname_chunks <- function(path) {
  message(glue::glue("Scanning {path}..."))
  unname_chunks(path)
}

#' @template path
#' @template chunk_name_prefix
#' @rdname unname_chunks
#' @export
unname_all_chunks <- function(path, chunk_name_prefix = NULL) {
  warning("please use unname_chunks() instead of unname_all_chunks()", call. = FALSE)
  unname_chunks(path, chunk_name_prefix = NULL)
}