R/addins.R

In TylerGrantSmith/packr: Tools for adding and removing namespace access colonoperators, `::` and `:::`

check_rstudio <- function() {
  is_installed("rstudioapi") && rstudioapi::isAvailable()
}

is_empty_selection <- function(selection) {
  identical(selection$range$start, selection$range$end)
}

get_token_start <- function(context, selection) {
  row <- selection$range$start[[1]]
  col <- selection$range$start[[2]]
  buffer <- context$contents[[row]]

  line_head <- substr(buffer, 1, col - 1)

  start <- regexec("[a-zA-Z._0-9:]+$", line_head)[[1]]

  if(start == -1) {
    start <- col
  }

  start
}

get_token_end <- function(context, selection) {
  row       <- selection$range$start[[1]]
  col       <- selection$range$start[[2]]
  buffer    <- context$contents[[row]]
  line_tail <- substr(buffer, col, nchar(buffer))
  offset    <- attr(regexec("^[a-zA-Z._0-9:]+", line_tail)[[1]], "match.length")
  offset    <- max(offset, 0)

  col + offset
}

assert_rstudio <- function() {
  if(!check_rstudio()) {
    abort(paste(
      "Either `rstudioapi` is missing or you are attempting",
      "to run this function from outside RStudio."))
  }
}


#' @importFrom purrr map_depth
scope_selection <- function(envir = caller_env()) {
  assert_rstudio()
  context_tracker <- ContextTracker$new()
  out <- map_depth(context_tracker$buffer, 2, scope, envir)
  if(is_null(out)) return()
  context_tracker$replace_in_context(map_depth(out, 2, ~.$text))
}

#' @importFrom purrr map_depth
unscope_selection <- function() {
  assert_rstudio()
  context_tracker <- ContextTracker$new()
  out <- map_depth(context_tracker$buffer, 2, unscope)
  if(is_null(out)) return()
  context_tracker$replace_in_context(map_depth(out, 2, ~.$text))

}