Config file

[atticus-sullivan]

Add the functionality to read options from a config file instead of/before reading CLI arguments.

Combined with #15 we could decide to allow (or even force) for the installation of hooks via this config file by requiring the config file being a lua script (similar to l3build.

Remember: Some options can be passed more than once and accumulate in the process (e.g. glossaries I think) in the config file we'd need to make these an array.

[atticus-sullivan]

Maybe the config file could even define new cli arguments (e.g. to define abbreviations like --final which disables quiet and disables memoization) 🤔

[atticus-sullivan]

One idea to read in the config file/script:

	-- Parse options from config file
	if fsutil.isfile(".cluttealtexrc.lua") then
		-- see https://ref.coddy.tech/lua/lua-sandboxing
		-- for us the main purpose is to avoid the config modifies the
		-- environment we're working in.
		-- Apart from that restriction, the config is allowed to execute
		-- anything.
		-- local sandbox = {
		-- 	print   = print,
		-- 	-- Add other functions here
		-- }
		-- setmetatable(sandbox, {__index = function(t:table, k:any)
		-- 	return error("Forbidden function/variable", 2) -- TODO deep-copy from _G on demand instead
		-- end})
		-- TODO move to a lua file to make use of _G (dynamically copy over/return on __index)
		local cfgChunk, err = loadfile(".cluttealtexrc.lua")
		if err then
			message.error("Error loading the config file '.cluttealtexrc.lua'")
			error(err)
		end
		local cfg: table
		do
			cfg = cfgChunk() as table
		end
		print(cfg.options)
		print(cfg.defaults)
	end

the goal eventually is to sandbox reading the config as much as possible. For now as a proof of concept, I'd say we keep it in the global state and avoid splitting into a new .lua (no teal) file.

[atticus-sullivan]

Question: How to handle all the watch related stuff. Via cli, the order is important but via cfg it's a table without strict ordering -> leads to non-determinism 👎

• Add an option to forbid setting an option directly via string from the cfg?
• Add an option to directly set the include/exclude paths for watch?

[atticus-sullivan]

Also --package-support should be accumulating