internal.R

#' @importFrom rstudioapi getSourceEditorContext insertText

add_prefix <- function(prefix) {
  a <- rstudioapi::getSourceEditorContext()
  s <- a$selection
  n <- length(s)
  # if no text is selected
  if (n == 1L && nchar(s[[1L]]$text) == 0L) {
    pos <- s[[1L]]$range$start
    pos[2L] <- 1
    rstudioapi::insertText(location = pos, text = prefix)
  } else {
    for (i in s)
      rstudioapi::insertText(location = i$range$start, text = prefix)
  }
}

add_multiline_prefix <- function(prefix, as_is = FALSE) {
  a <- rstudioapi::getSourceEditorContext()

  content <- strsplit(a$selection[[1]]$text, "\n")[[1]]

  # https://stackoverflow.com/a/47072999/3218296
  prefix_content <- iconv(content, "latin1", "ASCII", sub="")
  
  prefix_content <- gsub('^["]','',prefix_content)
  
  if (as_is) {
    # blockquote: keep blank lines, ignore indentation
    content <- paste0(prefix, content)
  } else {
    # list: ignore blank lines, keep indentation
    content[nzchar(content)] <-
      paste0(
        gsub("\\b.*$", "", prefix_content[nzchar(content)], perl = TRUE),
        prefix,
        gsub("^\\s*", "", content[nzchar(content)])
      )
  }
  
  if (length(content) > 0) {
    content <- paste0(content, "\n", collapse = "")
  } else {
    content <- ""
  }

  rstudioapi::modifyRange(
    location = a$selection[[1]]$range,
    text = content,
    id = a$id
  )
}

enclose <- function(prefix, postfix = prefix) {
  a <- rstudioapi::getSourceEditorContext()
  for (s in a$selection)
    rstudioapi::insertText(location = s$range, text = sprintf("%s%s%s", prefix, s$text, postfix))
}