R/replace_string_in_file.R

In SticsRPacks/SticsRFiles: Read and Modify 'STICS' Input/Output Files

#' Replacing a string in a file
#'
#' @description Replacing occurrences of a string by another one,
#' in place or creating a new file
#'
#' @param file_path The path to the file
#' @param target_string The target string to replace
#' @param replace_string The replacing string
#' @param new_file_path The newly-created file path
#'
#'
#' @keywords internal
#'
#' @noRd
#'
replace_string_in_file <- function(
    file_path,
    target_string,
    replace_string,
    new_file_path = NULL) {
  if (!file.exists(file_path)) {
    warning(paste(file_path, "doesn't exist, aborting !"))
    return()
  }
  in_place <- "i"
  redirect <- ""
  if (!base::is.null(new_file_path)) {
    in_place <- ""
    redirect <- paste(" >", new_file_path)
  }
  cmd <- paste0(
    "perl -p",
    in_place,
    " -e 's/",
    target_string,
    "/",
    replace_string,
    "/g ' ",
    file_path,
    redirect
  )

  system(cmd)
}