moonc

#!/usr/bin/env lua

local argparse = require "argparse"
local lfs = require "lfs"

local parser = argparse()

parser:flag("-l --lint", "Perform a lint on the file instead of compiling")

parser:flag("-v --version", "Print version")
parser:flag("-w --watch", "Watch file/directory for updates")
parser:option("--transform", "Transform syntax tree with module")

parser:mutex(
  parser:option("-t --output-to", "Specify where to place compiled files"),
  parser:option("-o", "Write output to file"),
  parser:flag("-p", "Write output to standard output"),
  parser:flag("-T", "Write parse tree instead of code (to stdout)"),
  parser:flag("-b", "Write parse and compile time instead of code(to stdout)"),
  parser:flag("-X", "Write line rewrite map instead of code (to stdout)")
)

parser:flag("-",
  "Read from standard in, print to standard out (Must be only argument)")

local read_stdin = arg[1] == "-" -- luacheck: ignore 113

if not read_stdin then
  parser:argument("file/directory"):args("*")
else
  if arg[2] ~= nil then
    io.stderr:write("- must be the only argument\n")
    os.exit(1)
  end
end

local opts = read_stdin and {} or parser:parse()

if opts.version then
  local v = require "moonscript.version"
  v.print_version()
  os.exit()
end

if not read_stdin and #opts["file/directory"] == 0 then
  io.stderr:write(parser:get_help())
  os.exit()
end

function log_msg(...)
  if not opts.p then
    io.stderr:write(table.concat({...}, " ") .. "\n")
  end
end

local moonc = require("moonscript.cmd.moonc")
local util = require "moonscript.util"
local normalize_dir = moonc.normalize_dir
local compile_and_write = moonc.compile_and_write
local path_to_target = moonc.path_to_target

local function scan_directory(root, collected)
  root = normalize_dir(root)
  collected = collected or {}

  for fname in lfs.dir(root) do
    if not fname:match("^%.") then
      local full_path = root..fname

      if lfs.attributes(full_path, "mode") == "directory" then
        scan_directory(full_path, collected)
      elseif fname:match("%.moon$") then
        table.insert(collected, full_path)
      end
    end
  end

  return collected
end

local function remove_dups(tbl, key_fn)
  local hash = {}
  local final = {}

  for _, v in ipairs(tbl) do
    local dup_key = key_fn and key_fn(v) or v
    if not hash[dup_key] then
      table.insert(final, v)
      hash[dup_key] = true
    end
  end

  return final
end

-- creates tuples of input and target
local function get_files(fname, files)
  files = files or {}

  if lfs.attributes(fname, "mode") == "directory" then
    for _, sub_fname in ipairs(scan_directory(fname)) do
      table.insert(files, {
        sub_fname,
        path_to_target(sub_fname, opts.output_to, fname)
      })
    end
  else
    table.insert(files, {
      fname,
      path_to_target(fname, opts.output_to)
    })
  end

  return files
end

if read_stdin then
  local parse = require "moonscript.parse"
  local compile = require "moonscript.compile"

  local text = io.stdin:read("*a")
  local tree, err = parse.string(text)

  if not tree then error(err) end
  local code, err, pos = compile.tree(tree)

  if not code then
    error(compile.format_error(err, pos, text))
  end

  print(code)
  os.exit()
end

local inputs = opts["file/directory"]

local files = {}
for _, input in ipairs(inputs) do
  get_files(input, files)
end

files = remove_dups(files, function(f)
  return f[2]
end)

-- returns an iterator that returns files that have been updated
local function create_watcher(files)
  local watchers = require("moonscript.cmd.watchers")

  if watchers.InotifyWacher:available() then
    return watchers.InotifyWacher(files):each_update()
  end

  return watchers.SleepWatcher(files):each_update()
end

if opts.watch then
  -- build function to check for lint or compile in watch
  local handle_file
  if opts.lint then
    local lint = require "moonscript.cmd.lint"
    handle_file = lint.lint_file
  else
    handle_file = compile_and_write
  end

  local watcher = create_watcher(files)
  -- catches interrupt error for ctl-c
  local protected = function()
    local status, file = true, watcher()
    if status then
      return file
    elseif file ~= "interrupted!" then
      error(file)
    end
  end

  for fname in protected do
    local target = path_to_target(fname, opts.t)

    if opts.o then
      target = opts.o
    end

    local success, err = handle_file(fname, target)
    if opts.lint then
      if success then
        io.stderr:write(success .. "\n\n")
      elseif err then
        io.stderr:write(fname .. "\n" .. err .. "\n\n")
      end
    elseif not success then
      io.stderr:write(table.concat({
        "",
        "Error: " .. fname,
        err,
        "\n",
      }, "\n"))
    elseif success == "build" then
      log_msg("Built", fname, "->", target)
    end
  end

  io.stderr:write("\nQuitting...\n")
elseif opts.lint then
  local has_linted_with_error;
  local lint = require "moonscript.cmd.lint"
  for _, tuple in pairs(files) do
    local fname = tuple[1]
    local res, err = lint.lint_file(fname)
    if res then
      has_linted_with_error = true
      io.stderr:write(res .. "\n\n")
    elseif err then
      has_linted_with_error = true
      io.stderr:write(fname .. "\n" .. err.. "\n\n")
    end
  end
  if has_linted_with_error then
    os.exit(1)
  end
else
  for _, tuple in ipairs(files) do
    local fname, target = util.unpack(tuple)
    if opts.o then
      target = opts.o
    end

    local success, err = compile_and_write(fname, target, {
      print = opts.p,
      fname = fname,
      benchmark = opts.b,
      show_posmap = opts.X,
      show_parse_tree = opts.T,
      transform_module = opts.transform
    })

    if not success then
      io.stderr:write(fname .. "\t" .. err .. "\n")
      os.exit(1)
    end
  end
end