TeX Live 2023 06-01以降の環境でl3buildでpLaTeXのテストをするためのやつ

build-platex-on-euptex.lua

-- File: build-platex-on-euptex.lua
--
-- usage:
-- ```build.lua
-- kpse.set_program_name("kpsewhich")
-- ...
-- dofile("build-platex-on-euptex.lua")
-- ```

-- Check if a file contains lines matching a pattern
local function check_pattern_in_file(filename, pattern)
  local f = io.open(filename, "r")
  if f then
    for line in f:lines() do
      if string.match(line, pattern) then
        f:close()
        return true
      end
    end
    f:close()
    return false
  else
    return false
  end
end

-- Check if platex based on e-upTeX
local function is_platex_euptex()
  local fmtutil_cnf = kpse.lookup("fmtutil.cnf")
  return check_pattern_in_file(fmtutil_cnf, "^platex%s+euptex%s+")
end

-- get platex's default internal kanji encoding
local function get_platex_kanji()
  if os.type == "windows" then
    return "sjis"
  else
    return "euc"
  end
end

-- overwrite platex format if platex based on e-upTeX.
if is_platex_euptex() then
  kanji = get_platex_kanji()
  specialformats = {
    latex = {
      ptex = {binary = "euptex", format = "platex", options = "-kanji-internal="..kanji}
    }
  }
end