show all the function names in a given set of R scripts using the treesitter package

function_names.R

# show all the function names in a given set of R scripts
function_definitions = function(files) {
  purrr:::map(files, function_definitions_script) |> 
    purrr::list_rbind()
}

function_definitions_script = function(file) {
  text = brio::read_lines(file) |>
    paste(collapse = "\n")
  
  language <- treesitter.r::language()
  parser <- treesitter::parser(language)
  tree = treesitter::parser_parse(parser, text)
  node = treesitter::tree_root_node(tree)
  
  query_source = '
    (
    (binary_operator
      lhs: (identifier) @name
      rhs: (function_definition))
    )
  '
  function_query <- treesitter::query(language, query_source)
  captures <- treesitter::query_captures(function_query, node)
  
  purrr::map(captures$node, extract_node_info) |> 
    purrr::list_rbind() |> 
    dplyr::mutate(file = file)
}

extract_node_info = function(node) {
  tibble::tibble(
    name = treesitter::node_text(node),
    line = treesitter::node_range(node)$start_point$row + 1
  )
}

Thank you for this! I've adapted it to find just function names based on text instead of a file. I really appreciate it!

find_function_names <- function(text) {
  language <- treesitter.r::language()
  parser <- treesitter::parser(language)
  tree <- treesitter::parser_parse(parser, text)
  node <- treesitter::tree_root_node(tree)
  
  query_source <- "
    (
    (binary_operator
      lhs: (identifier) @name
      rhs: (function_definition))
    )
  "
  function_query <- treesitter::query(language, query_source)
  captures <- treesitter::query_captures(function_query, node)
  
  vapply(captures$node, treesitter::node_text, character(1)) 
}